Editing Appendicitis

{{Short description|Inflammation of the appendix}}
{{Duplicated citations|reason=[[User:Polygnotus/DuplicateReferences|DuplicateReferences]] detected:<br>
* https://link.springer.com/10.1007/s00423-023-02935-z (refs: 76, 91)<br>
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{{Infobox medical condition (new)
| image = Acute Appendicitis.jpg
| caption = An acutely inflamed and enlarged appendix, sliced lengthwise.
| field = [[General surgery]]
| synonyms = Epityphlitis<ref>{{cite web |title=appendicitis |work=Medical Dictionary |publisher=Merriam-Webster |url=http://www.merriam-webster.com/medical/epityphlitis |url-status=live |archive-url=https://web.archive.org/web/20131230235451/http://www.merriam-webster.com/medical/epityphlitis |archive-date=2013-12-30 }}</ref>
| symptoms = Periumbilical or right lower [[abdominal pain]], [[vomiting]], [[nausea]], [[anorexia (symptom)|decreased appetite]],<ref name=Graf1996/> [[fever|high fever]]
| complications = [[peritonitis|Abdominal inflammation]], [[sepsis]]<ref name=Hob1998/>
| onset = 
| duration = 
| causes = 
| risks = 
| diagnosis = Based on symptoms, [[medical imaging]], blood tests<ref name=Paul2003/>
| differential = [[Mesenteric adenitis]], [[cholecystitis]], [[psoas abscess]], [[abdominal aortic aneurysm]]<ref>{{cite book|last1=Ferri|first1=Fred F.|title=Ferri's differential diagnosis: a practical guide to the differential diagnosis of symptoms, signs, and clinical disorders|date=2010|publisher=Elsevier/Mosby|location=Philadelphia, PA|isbn=978-0-323-07699-9|pages = Chapter A|edition=2nd}}</ref>
| prevention = 
| treatment = [[appendectomy|Surgical removal of the appendix]], [[antibiotics]]<ref name=Har2012/><ref name=Antibiotics2012/>
| medication = 
| prognosis = 
| frequency = 11.6 million (2015)<!-- incidence table --><ref name=GBD2015Pre/>
| deaths = 50,100 (2015)<ref name=GBD2015De/>
| name = 
}}

<!-- Definition and symptoms -->
'''Appendicitis''' is [[inflammation]] of the [[Appendix (anatomy)|appendix]].<ref name=Graf1996/> Symptoms commonly include right lower [[abdominal pain]], [[nausea]], [[vomiting]], [[fever]] and [[anorexia (symptom)|decreased appetite]].<ref name=Graf1996/> However, approximately 40% of people do not have these typical symptoms.<ref name=Graf1996>{{cite journal | vauthors = Graffeo CS, Counselman FL | title = Appendicitis | journal = Emergency Medicine Clinics of North America | volume = 14 | issue = 4 | pages = 653–671 | date = November 1996 | pmid = 8921763 | doi = 10.1016/s0733-8627(05)70273-x }}</ref> Severe complications of a ruptured appendix include widespread, agonising and awful [[peritonitis|inflammation of the inner lining of the abdominal wall]] and [[sepsis]].<ref name=Hob1998/>

<!-- Cause -->
Appendicitis is primarily caused by a blockage of the [[Lumen (anatomy)|hollow portion]] in the appendix.<ref name=Piep1982>{{cite journal | vauthors = Pieper R, Kager L, Tidefeldt U | title = Obstruction of appendix vermiformis causing acute appendicitis. An experimental study in the rabbit | journal = Acta Chirurgica Scandinavica | volume = 148 | issue = 1 | pages = 63–72 | year = 1982 | pmid = 7136413 }}</ref> This blockage typically results from a [[Fecalith|faecolith]], a calcified "stone" made of feces.<ref name=Har2012/> Some studies show a correlation between appendicoliths and disease severity.<ref>{{cite journal |last1=Dölling |first1=M |last2=Rahimli |first2=M |last3=Pachmann |first3=J |title=Hidden Appendicoliths and Their Impact on the Severity and Treatment of Acute Appendicitis |journal=Journal of Clinical Medicine |date=2024 |volume=13 |issue=14 |page=4166 |doi=10.3390/jcm13144166|doi-access=free |pmid=39064205 |pmc=11278186 }}</ref> Other factors such as inflamed [[Mucosa-associated lymphoid tissue|lymphoid tissue]] from a viral infection, [[Human parasite|intestinal parasites]], [[gallstone]], or [[Neoplasm|tumors]] may also lead to this blockage.<ref name=Har2012>{{cite book|editor-last1=Longo|editor-first1=Dan L.|display-editors=etal|title=Harrison's principles of internal medicine.|date=2012|publisher=McGraw-Hill|location=New York|isbn=978-0-07-174889-6|pages = Chapter 300|edition=18th|url=http://accessmedicine.mhmedical.com/content.aspx?bookid=331&Sectionid=40727094|access-date=6 November 2014|url-status=live|archive-url=https://web.archive.org/web/20160330064145/http://accessmedicine.mhmedical.com/content.aspx?bookid=331&sectionid=40727094|archive-date=30 March 2016}}</ref> When the appendix becomes blocked, it experiences increased pressure, reduced blood flow, and bacterial growth, resulting in inflammation.<ref name=Har2012/><ref name=Tint2011>{{cite book|editor-last1=Tintinalli|editor-first1=Judith E. |title=Emergency medicine: a comprehensive study guide|date=2011|publisher=McGraw-Hill|location=New York|isbn=978-0-07-174467-6|pages = Chapter 84|edition=7th |url=http://accessmedicine.mhmedical.com/content.aspx?bookid=348&Sectionid=40381551 |access-date=6 November 2014|url-status=live|archive-url=https://web.archive.org/web/20161222153008/http://accessmedicine.mhmedical.com/content.aspx?bookid=348&Sectionid=40381551|archive-date=22 December 2016}}</ref> This combination of factors causes tissue injury and, ultimately, tissue death.<ref name =Schw2010>{{cite book|title=Schwartz's principles of surgery|date=2010|publisher=McGraw-Hill, Medical Pub. Division|location=New York|isbn=978-0-07-154770-3|pages = Chapter 30|edition=9th}}</ref> If this process is left untreated, it can lead to the appendix rupturing, which releases bacteria into the [[abdominal cavity]], potentially leading to severe complications.<ref name =Schw2010/><ref name=Barrett2013>{{cite journal | vauthors = Barrett ML, Hines AL, Andrews RM | title = Trends in Rates of Perforated Appendix, 2001–2010 | journal = Healthcare Cost and Utilization Project (HCUP) Statistical Brief #159 |date= July 2013 |publisher= Agency for Healthcare Research and Quality |location= Rockville, MD | pmid = 24199256 | url = http://www.hcup-us.ahrq.gov/reports/statbriefs/sb159.pdf | url-status = live | archive-url = https://web.archive.org/web/20161020110746/http://www.hcup-us.ahrq.gov/reports/statbriefs/sb159.pdf | archive-date = 2016-10-20 }}</ref>

<!-- Diagnosis -->
The diagnosis of appendicitis is largely based on the person's signs and symptoms.<ref name=Tint2011/> In cases where the diagnosis is unclear, close observation, [[medical imaging]], and laboratory tests can be helpful.<ref name=Paul2003/> The two most commonly used imaging tests for diagnosing appendicitis are ultrasound and computed tomography (CT scan).<ref name=Paul2003>{{cite journal | vauthors = Paulson EK, Kalady MF, Pappas TN | title = Clinical practice. Suspected appendicitis | journal = The New England Journal of Medicine | volume = 348 | issue = 3 | pages = 236–242 | date = January 2003 | pmid = 12529465 | doi = 10.1056/nejmcp013351 | url = http://faculty.vet.upenn.edu/gastro/documents/NEJMappendicitis.pdf | access-date = 2017-11-01 | archive-url = https://web.archive.org/web/20170922005733/http://faculty.vet.upenn.edu/gastro/documents/NEJMappendicitis.pdf | archive-date = 2017-09-22 | url-status = dead }}</ref> CT scan is more accurate than ultrasound in detecting acute appendicitis.<ref name=Shogilev2014>{{cite journal | vauthors = Shogilev DJ, Duus N, Odom SR, Shapiro NI | title = Diagnosing appendicitis: evidence-based review of the diagnostic approach in 2014 | journal = The Western Journal of Emergency Medicine | volume = 15 | issue = 7 | pages = 859–871 | date = November 2014 | pmid = 25493136 | pmc = 4251237 | doi = 10.5811/westjem.2014.9.21568 | type = Review }}</ref> However, ultrasound may be preferred as the first imaging test in children and pregnant women because of the risks associated with radiation exposure from CT scans.<ref name=Paul2003/> Although ultrasound may aid in diagnosis, its main role is in identifying important differentials, such as ovarian pathology in females or mesenteric adenitis in children.

[[File:En.Wikipedia-VideoWiki-Appendicitis.webm|thumb|thumbtime=1:10|upright=1.4|Video summary ([[Wikipedia:VideoWiki/Appendicitis|script]])]]
The standard treatment for acute appendicitis involves the [[Appendectomy|surgical removal of the inflamed appendix]].<ref name=Har2012/><ref name=Tint2011/> This procedure can be performed either through an open incision in the abdomen ([[laparotomy]]) or using minimally invasive techniques with small incisions and cameras ([[laparoscopy]]). Surgery is essential to reduce the risk of complications or potential death associated with the rupture of the appendix.<ref name=Hob1998>{{Cite journal |last=Hobler |first=K. |date=Spring 1998 |title=Acute and Suppurative Appendicitis: Disease Duration and its Implications for Quality Improvement |url=http://www.thepermanentejournal.org/files/Spring1998/appendicitis.pdf |journal=Permanente Medical Journal |volume=2 |issue=2 |access-date=2016-10-26 |archive-date=2021-03-06 |archive-url=https://web.archive.org/web/20210306021312/https://www.thepermanentejournal.org/files/Spring1998/appendicitis.pdf |url-status=dead }}</ref> [[Antibiotic]]s may be equally effective in certain cases of non-ruptured appendicitis,<ref name="BJS paper">{{cite journal |last1=Javanmard-Emamghissi |first1=Hannah |title=Antibiotics as first-line alternative to appendicectomy in adult appendicitis: 90-day follow-up from a prospective, multicentre cohort study |journal=The British Journal of Surgery |year=2021 |volume=108 |issue=11 |pages=1351–1359 |doi=10.1093/bjs/znab287 |pmid=34476484 |pmc=8499866 |url=https://academic.oup.com/bjs/advance-article/doi/10.1093/bjs/znab287/6363089?searchresult=1 |access-date=8 September 2021}}</ref><ref name=Antibiotics2012>{{cite journal | vauthors = Varadhan KK, Neal KR, Lobo DN | title = Safety and efficacy of antibiotics compared with appendicectomy for treatment of uncomplicated acute appendicitis: meta-analysis of randomised controlled trials | journal = BMJ | volume = 344 | pages = e2156 | date = April 2012 | pmid = 22491789 | pmc = 3320713 | doi = 10.1136/bmj.e2156 }}</ref><ref>{{Cite web |date=2020-11-24 |title=Appendicitis: Surgical vs. Medical Treatment {{!}} Science-Based Medicine |url=https://sciencebasedmedicine.org/appendicitis-surgical-vs-medical-treatment/ |access-date=2022-11-04 |website=sciencebasedmedicine.org |language=en-US}}</ref> but 31% will undergo appendectomy within one year.<ref name="ReferenceB">{{Cite journal |last1=Doleman |first1=Brett |last2=Fonnes |first2=Siv |last3=Lund |first3=Jon N. |last4=Boyd-Carson |first4=Hannah |last5=Javanmard-Emamghissi |first5=Hannah |last6=Moug |first6=Susan |last7=Hollyman |first7=Marianne |last8=Tierney |first8=Gillian |last9=Tou |first9=Samson |last10=Williams |first10=John P. |date=2024-04-29 |title=Appendectomy versus antibiotic treatment for acute appendicitis |journal=The Cochrane Database of Systematic Reviews |volume=2024 |issue=4 |pages=CD015038 |doi=10.1002/14651858.CD015038.pub2 |issn=1469-493X |pmc=11057219 |pmid=38682788}}</ref> It is one of the most common and significant causes of sudden abdominal [[pain]]. In 2015, approximately 11.6 million cases of appendicitis were reported, resulting in around 50,100 deaths worldwide.<ref name=GBD2015Pre>{{cite journal | vauthors = ((GBD 2015 Disease and Injury Incidence and Prevalence Collaborators)) | title = Global, regional, and national incidence, prevalence, and years lived with disability for 310 diseases and injuries, 1990–2015: a systematic analysis for the Global Burden of Disease Study 2015 | journal = Lancet | volume = 388 | issue = 10053 | pages = 1545–1602 | date = October 2016 | pmid = 27733282 | pmc = 5055577 | doi = 10.1016/S0140-6736(16)31678-6 |doi-access=free}}</ref><ref name=GBD2015De>{{cite journal | vauthors = ((GBD 2015 Mortality and Causes of Death Collaborators)) | title = Global, regional, and national life expectancy, all-cause mortality, and cause-specific mortality for 249 causes of death, 1980–2015: a systematic analysis for the Global Burden of Disease Study 2015 | journal = Lancet | volume = 388 | issue = 10053 | pages = 1459–1544 | date = October 2016 | pmid = 27733281 | pmc = 5388903 | doi = 10.1016/s0140-6736(16)31012-1 |doi-access=free}}</ref> In the United States, appendicitis is one of the most common causes of sudden abdominal pain requiring surgery.<ref name=Graf1996/> Annually, more than 300,000 individuals in the United States undergo surgical removal of their appendix.<ref>{{cite journal | vauthors = Mason RJ | title = Surgery for appendicitis: is it necessary? | journal = Surgical Infections | volume = 9 | issue = 4 | pages = 481–488 | date = August 2008 | pmid = 18687030 | doi = 10.1089/sur.2007.079 }}</ref>
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==Signs and symptoms==
[[File:McBurney's point.jpg|thumb|left|upright=1.3|Location of [[McBurney's point]] (1), located two-thirds the distance from the umbilicus (2) to the right anterior superior iliac spine (3)]]
The presentation of acute appendicitis includes acute abdominal pain, nausea, vomiting, and fever. As the appendix becomes more swollen and inflamed, it begins to irritate the adjoining abdominal wall. This leads the pain to localize at [[Quadrants and regions of abdomen|the right lower quadrant]]. This classic migration of pain may not appear in children under three years. This pain can be triggered by a sharp pain feeling. Pain from appendicitis may begin as dull pain around the navel. After several hours, the pain usually migrates towards the right lower quadrant, where it becomes localized. Symptoms include localized findings in the right [[iliac fossa]]. The abdominal wall becomes very sensitive to gentle pressure ([[palpation]]). There is pain in the sudden release of deep tension in the lower abdomen ([[Blumberg's sign]]). If the appendix is retrocecal (localized behind the [[cecum]]), even deep pressure in the right lower quadrant may fail to elicit tenderness (silent appendix). This is because the [[cecum]], distended with gas, protects the inflamed appendix from pressure. Similarly, if the appendix lies entirely within the pelvis, there is typically a complete absence of abdominal rigidity. In such cases, a digital [[rectal examination]] elicits tenderness in the rectovesical pouch. Coughing causes point tenderness in this area ([[McBurney's point]]), called [[Dunphy's sign]].{{medical citation needed|date=August 2023}}

==Causes==
[[File:Stomach colon rectum diagram-en.svg|thumb|Location of the appendix in the [[digestive system]]]]
[[File:3D still showing appendicitis.jpg|alt=3D still showing appendicitis.|thumb|3D model of appendicitis.]]
Acute appendicitis seems to be the result of a primary obstruction of the [[Appendix (anatomy)|appendix]].<ref name=Wang1937>{{Cite journal|vauthors=[[Owen Harding Wangensteen|Wangensteen OH]], Bowers WF |title=Significance of the obstructive factor in the genesis of acute appendicitis |journal=Archives of Surgery |volume=34 |issue= 3|pages=496–526 |year=1937|doi=10.1001/archsurg.1937.01190090121006}}</ref><ref name=Piep1982/> Once this obstruction occurs, the appendix becomes filled with [[mucus]] and swells. This continued production of mucus leads to increased pressures within the lumen and the walls of the appendix. The increased pressure results in [[thrombosis]] and [[Vascular occlusion|occlusion]] of the small vessels, and stasis of [[Lymphatic system|lymphatic flow]]. At this point, spontaneous recovery rarely occurs. As the occlusion of blood vessels progresses, the appendix becomes [[Ischemia|ischemic]] and then [[Necrosis|necrotic]]. As [[bacteria]] begin to leak out through the dying walls, [[pus]] forms within and around the appendix (suppuration). The result is appendiceal rupture (a 'burst appendix') causing [[peritonitis]], which may lead to [[sepsis]] and in rare cases, [[death]]. These events are responsible for the slowly evolving abdominal pain and other commonly associated symptoms.<ref name=Schw2010/>

The causative agents include [[bezoar]]s, foreign bodies, [[physical trauma|trauma]],<ref>{{Cite journal |last=Fowler |first=Royal H. |date=April 1938 |title=The Rare Incidence of Acute Appendicitis Resulting from External Trauma |journal=Annals of Surgery |volume=107 |issue=4 |pages=529–539 |doi=10.1097/00000658-193804000-00007 |issn=0003-4932 |pmc=1386836 |pmid=17857157}}</ref><ref>{{Cite journal |last1=Toumi |first1=Zaher |last2=Chan |first2=Anthony |last3=Hadfield |first3=Matthew B. |last4=Hulton |first4=Neil R. |date=September 2010 |title=Systematic review of blunt abdominal trauma as a cause of acute appendicitis |journal=Annals of the Royal College of Surgeons of England |volume=92 |issue=6 |pages=477–482 |doi=10.1308/003588410X12664192075936 |issn=1478-7083 |pmc=3182788 |pmid=20513274}}</ref> [[Lymphadenopathy|lymphadenitis]] and, most commonly, calcified fecal deposits that are known as [[appendicolith]]s or [[fecalith]]s.<ref>{{cite journal | last1= Hollerman |first1=J. |last2=Bernstein |first2=MA |last3=Kottamasu |first3=SR |last4=Sirr |first4=SA | year = 1988 | title = Acute recurrent appendicitis with appendicolith | journal =The American Journal of Emergency Medicine | volume = 6 | issue = 6| pages = 614–617 | doi=10.1016/0735-6757(88)90105-2|pmid=3052484 }}</ref><ref name=":0" /> The occurrence of [[Fecaloma|obstructing fecalith]]s has attracted attention since their presence in people with appendicitis is higher in developed than in developing countries.<ref>{{cite journal | vauthors = Jones BA, Demetriades D, Segal I, Burkitt DP | title = The prevalence of appendiceal fecaliths in patients with and without appendicitis. A comparative study from Canada and South Africa | journal = Annals of Surgery | volume = 202 | issue = 1 | pages = 80–82 | date = July 1985 | pmid = 2990360 | pmc = 1250841 | doi = 10.1097/00000658-198507000-00013 }}</ref> In addition, an appendiceal fecalith is commonly associated with complicated appendicitis.<ref>{{cite journal | vauthors = Nitecki S, Karmeli R, Sarr MG | title = Appendiceal calculi and fecaliths as indications for appendectomy | journal = Surgery, Gynecology & Obstetrics | volume = 171 | issue = 3 | pages = 185–188 | date = September 1990 | pmid = 2385810 }}</ref> Fecal stasis and arrest may play a role, as demonstrated by people with acute appendicitis having fewer bowel movements per week compared with healthy controls.<ref name=":0">{{cite journal | vauthors = Dehghan A, Moaddab AH, Mozafarpour S | title = An unusual localization of trichobezoar in the appendix | journal = The Turkish Journal of Gastroenterology | volume = 22 | issue = 3 | pages = 357–358 | date = June 2011 | pmid = 21805435 | doi = 10.4318/tjg.2011.0232 }}</ref><ref>{{cite journal | vauthors = Arnbjörnsson E | title = Acute appendicitis related to faecal stasis | journal = Annales Chirurgiae et Gynaecologiae | volume = 74 | issue = 2 | pages = 90–93 | year = 1985 | pmid = 2992354 }}</ref>

The occurrence of a fecalith in the appendix was thought to be attributed to a right-sided fecal retention reservoir in the colon and a prolonged transit time. However, a prolonged transit time was not observed in subsequent studies.<ref>{{cite journal | vauthors = Raahave D, Christensen E, Moeller H, Kirkeby LT, Loud FB, Knudsen LL | title = Origin of acute appendicitis: fecal retention in colonic reservoirs: a case-control study | journal = Surgical Infections | volume = 8 | issue = 1 | pages = 55–62 | date = February 2007 | pmid = 17381397 | doi = 10.1089/sur.2005.04250 }}</ref> [[Diverticular disease]] and [[adenomatous polyps]] were historically unknown and [[colon cancer]] was exceedingly rare in communities where appendicitis itself was rare or absent, such as various African communities. Studies have implicated a transition to a [[Western diet]] lower in [[Dietary fiber|fiber]] in rising frequencies of appendicitis as well as the other aforementioned colonic diseases in these communities.<ref>{{cite journal | vauthors = Burkitt DP | title = The aetiology of appendicitis | journal = The British Journal of Surgery | volume = 58 | issue = 9 | pages = 695–699 | date = September 1971 | pmid = 4937032 | doi = 10.1002/bjs.1800580916 | pmc = 1598350 }}</ref><ref>{{cite journal | vauthors = Segal I, Walker AR | title = Diverticular disease in urban Africans in South Africa | journal = Digestion | volume = 24 | issue = 1 | pages = 42–46 | year = 1982 | pmid = 6813167 | doi = 10.1159/000198773 }}</ref> And acute appendicitis has been shown to occur antecedent to cancer in the colon and rectum.<ref>{{cite journal | vauthors = Arnbjörnsson E | title = Acute appendicitis as a sign of a colorectal carcinoma | journal = Journal of Surgical Oncology | volume = 20 | issue = 1 | pages = 17–20 | date = May 1982 | pmid = 7078180 | doi = 10.1002/jso.2930200105 | s2cid = 30187238 }}</ref> Several studies offer evidence that a low fiber intake is involved in the pathogenesis of appendicitis.<ref>{{cite journal | vauthors = Burkitt DP, Walker AR, Painter NS | title = Effect of dietary fibre on stools and the transit-times, and its role in the causation of disease | journal = Lancet | volume = 2 | issue = 7792 | pages = 1408–1412 | date = December 1972 | pmid = 4118696 | doi = 10.1016/S0140-6736(72)92974-1 }}</ref><ref>{{cite journal | vauthors = Adamidis D, Roma-Giannikou E, Karamolegou K, Tselalidou E, Constantopoulos A | title = Fiber intake and childhood appendicitis | journal = International Journal of Food Sciences and Nutrition | volume = 51 | issue = 3 | pages = 153–157 | date = May 2000 | pmid = 10945110 | doi = 10.1080/09637480050029647 | s2cid = 218989618 }}</ref><ref>{{cite journal | vauthors = Hugh TB, Hugh TJ | title = Appendicectomy – becoming a rare event? | journal = The Medical Journal of Australia | volume = 175 | issue = 1 | pages = 7–8 | date = July 2001 | doi = 10.5694/j.1326-5377.2001.tb143501.x | pmid = 11476215 | s2cid = 33795090 | url = http://www.mja.com.au/public/issues/175_01_020701/hugh/hugh.html | url-status = live | archive-url = https://web.archive.org/web/20060826042124/http://www.mja.com.au/public/issues/175_01_020701/hugh/hugh.html | archive-date = 2006-08-26 }}</ref> This low intake of dietary fiber is in accordance with the occurrence of a right-sided fecal reservoir and the fact that dietary fiber reduces transit time.<ref>{{cite journal | vauthors = Gear JS, Brodribb AJ, Ware A, Mann JI | title = Fibre and bowel transit times | journal = The British Journal of Nutrition | volume = 45 | issue = 1 | pages = 77–82 | date = January 1981 | pmid = 6258626 | doi = 10.1079/BJN19810078 | doi-access = free }}</ref>

==Diagnosis==
{{ImageStackPopup
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|list    = User:Doc_James/Appendicitis_CT#medical
|caption = [[CT scan]] showing acute appendicitis
|title   = 
|file    = [[File:Appendicitis_(CT_angiogram)_(Radiopaedia_154713-127660_Axial_1).jpg|link=|thumb|upright=1.3|CT scan showing acute appendicitis]]
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The physician will ask questions to get the [[health history]], assess the patient's [[Signs and symptoms|symptoms]], do a complete [[Physical examination|physical exam]], and order both laboratory and imaging tests.<ref name=NIDDK>National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK). (n.d.). Appendicitis – Diagnosis. Retrieved September 21, 2023, from https://www.niddk.nih.gov/health-information/digestive-diseases/appendicitis/diagnosis</ref> Appendicitis symptoms fall into two categories, typical and atypical.<ref name="typical"/>

Typical appendicitis is characterized by a migratory right [[iliac fossa]] pain associated with nausea, and anorexia, which can occur with or without vomiting and localized muscle stiffness/ generalized [[Abdominal guarding|guarding]].<ref name=typical>{{cite journal |last1=Echevarria |first1=S |last2=Rauf |first2=F |last3=Hussain |first3=N |last4=Zaka |first4=H |last5=Farwa |first5=UE |last6=Ahsan |first6=N |last7=Broomfield |first7=A |last8=Akbar |first8=A |last9=Khawaja |first9=UA |title=Typical and Atypical Presentations of Appendicitis and Their Implications for Diagnosis and Treatment: A Literature Review. |journal=Cureus |date=April 2023 |volume=15 |issue=4 |pages=e37024 |doi=10.7759/cureus.37024 |doi-access=free |pmid=37143626|pmc=10152406 }}</ref> It is possible the pain could localize to [[Left lower quadrant|the left lower quadrant]] in people with [[situs inversus totalis]].<ref>{{cite journal |last1=Oh |first1=JS |last2=Kim |first2=KW |last3=Cho |first3=HJ |title=Left-sided appendicitis in a patient with situs inversus totalis. |journal=Journal of the Korean Surgical Society |date=September 2012 |volume=83 |issue=3 |pages=175–178 |doi=10.4174/jkss.2012.83.3.175 |pmid=22977765|pmc=3433555 }}</ref> The combination of migrated [[Umbilical region|umbilical]] pain to the right [[Quadrants and regions of abdomen|lower quadrant]], loss of appetite for food, nausea, unsustained [[vomiting]], and mild [[fever]] is classic.<ref name="typical" />

Atypical histories lack this typical progression and may include pain in the right lower quadrant as an initial symptom. Irritation of the peritoneum (inside lining of the abdominal wall) can lead to increased pain on movement, or jolting, for example going over [[speed bump]]s.<ref>{{cite journal | vauthors = Ashdown HF, D'Souza N, Karim D, Stevens RJ, Huang A, Harnden A | title = Pain over speed bumps in diagnosis of acute appendicitis: diagnostic accuracy study | journal = BMJ | volume = 345 | issue = dec14 14 | pages = e8012 | date = December 2012 | pmid = 23247977 | pmc = 3524367 | doi = 10.1136/bmj.e8012 }}</ref> Atypical histories often require imaging with ultrasound or CT scanning.<ref name=Hob1998/>

===Signs===
During the early stages of appendicitis diagnosis, it is common for [[Physical examination|physical exams]] to present inconspicuous findings. Signs of inflammation become noticeable as the disease progresses. These signs may include<ref>Jones MW, Lopez RA, Deppen JG. Appendicitis. [Updated 2023 April 24]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2023 Jan. Available from: https://www.ncbi.nlm.nih.gov/books/NBK493193/</ref>
* [[Aure-Rozanova's sign]]: Increased pain on palpation with a finger in the right [[Lumbar triangle|inferior lumbar triangle]] (can be a positive [[Blumberg's sign]]).<ref name="SachdevaDutta2012">{{cite book|last1=Sachdeva|first1=Anupam|last2=Dutta|first2=AK|title=Advances in Pediatrics|date= 2012|publisher=JP Medical |isbn=978-93-5025-777-7|page = 1432}}</ref>
* [[Bartomier-Michelson's sign]]: Increased pain on palpation at the right iliac region as the person being examined lies on their left side compared to when they lie on their back.<ref name="SachdevaDutta2012"/>
* [[Dunphy's sign]]: Increased pain in the right lower quadrant by coughing.<ref name=Sign>{{cite book |last1=Al-Salem |first1=Ahmed H. |title=Atlas of Pediatric Surgery: Principles and Treatment |date=2020 |publisher=Springer |location=Cham |isbn=978-3-030-29210-2 |edition=1st }}</ref>
* [[Hamburger sign]]: The patient refuses to eat ([[anorexia (symptom)|anorexia]] is 80% [[Sensitivity and specificity|sensitive]] for appendicitis)<ref name="VirgilioFrank2015">{{cite book|last1=Virgilio|first1=Christian de|last2=Frank|first2=Paul N.|last3=Grigorian|first3=Areg|title=Surgery|date= 2015|publisher=Springer|language=en |isbn=978-1-4939-1726-6|page = 215}}</ref>
* [[Kocher's sign (appendicitis)|Kocher's sign]] (Kosher's sign): From the person's medical history, the start of pain in the umbilical region with a subsequent shift to the right iliac region.<ref name="SachdevaDutta2012"/>
* [[Massouh's sign]]: Developed in and popular in southwest England, the examiner performs a firm swish with their index and middle finger across the abdomen from the [[xiphoid process]] to the left and the right iliac fossa.<ref name="Sign"/>
* [[Obturator sign]]: The person being evaluated lies on her or his back with the hip and knee both flexed at ninety degrees. The examiner holds the person's ankle with one hand and knee with the other hand. The examiner rotates the hip by moving the person's ankle away from their body while allowing the knee to move only inward. A positive test is pain with internal rotation of the hip.<ref name="WolfsonCloutier2014">{{cite book|last1=Wolfson|first1=Allan B.|last2=Cloutier|first2=Robert L.|last3=Hendey|first3=Gregory W.|first4=Louis J.|last4=Ling|first5=Jeffrey J.|last5=Schaider|first6=Carlo L.|last6=Rosen|title=Harwood-Nuss' Clinical Practice of Emergency Medicine|url=https://books.google.com/books?id=cgMYBQAAQBAJ&pg=PT5810|access-date=15 June 2016|date= 2014|publisher=Wolters Kluwer Health|language=en|isbn=978-1-4698-8948-1|page = 5810|quote=Physical signs classically associated with acute appendicitis include Rovsing sign, psoas sign, and obturator sign.|url-status=live|archive-url=https://web.archive.org/web/20170910171627/https://books.google.com/books?id=cgMYBQAAQBAJ&pg=PT5810|archive-date=10 September 2017}}</ref>
* [[Psoas sign]], also known as "Obraztsova's sign", is right lower-quadrant pain that is produced with either the passive extension of the right hip or by the active flexion of the person's right hip while supine. The pain that is elicited is due to inflammation of the peritoneum overlying the iliopsoas muscles and inflammation of the psoas muscles themselves. Straightening out the leg causes pain because it stretches these muscles while flexing the hip activates the iliopsoas and causes pain.<ref name="WolfsonCloutier2014"/>
* [[Rovsing's sign]]: Pain in the lower right abdominal quadrant with continuous deep palpation starting from the left [[iliac fossa]] upwards (counterclockwise along the colon). The thought is there will be increased pressure around the appendix by pushing bowel contents and air toward the [[ileocaecal valve]] provoking right-sided abdominal pain.<ref>{{cite journal |last=Rovsing |first=N.T. |date=1907 |title=Indirektes Hervorrufen des typischen Schmerzes an McBurney's Punkt. Ein Beitrag zur diagnostik der Appendicitis und Typhlitis |journal=Zentralblatt für Chirurgie |location=Leipzig |volume=34 |pages=1257–1259|language=de}}</ref>
* [[Rosenstein's sign]] (Sitkovsky's sign): Increased pain in the right iliac region as the person is being examined lies on their left side.<ref name="DunsterHunter1922">{{cite book|last1=Dunster|first1=Edward Swift|last2=Hunter|first2=James Bradbridge|last3=Sajous|first3=Charles Euchariste de Medicis|first4=Frank Pierce |last4=Foster |first5=Gregory |last5=Stragnell |first6=Henry J. |last6=Klaunberg |first7=Félix |last7=Martí-Ibáñez |title=International Record of Medicine and General Practice Clinics|year=1922|publisher=New York Medical Journal |language=en|pages = 663}}</ref>
* Perman's sign: In acute appendicitis palpation in the left iliac fossa may produce pain in the right iliac fossa.<ref>Emil Samuel Perman (1856–1946), "About the indications for surgery in appendicitis and an account of cases of Sabbatsberg Hospital in Hygiea, 1904.</ref>

===Laboratory tests===

While there is no laboratory test specific for appendicitis, a [[complete blood count]] (CBC) is done to check for signs of infection or inflammation. Although 70–90 percent of people with appendicitis may have an elevated [[white blood cell count|white blood cell (WBC) count]], many other abdominal and pelvic conditions can cause the WBC count to be elevated.<ref name=CDEM>{{cite web|title=Appendicitis |first=Charmaine |last=Gregory |work=CDEM Self Study Modules |publisher=Clerkship Directors in Emergency Medicine |date=2010 |url=http://www.cdemcurriculum.org/ssm/gi/appy/appy.php |url-status=usurped |archive-url=https://web.archive.org/web/20131130062201/http://www.cdemcurriculum.org/ssm/gi/appy/appy.php |archive-date=2013-11-30 }}</ref> However, a high [[White blood cell count|WBC count]] may not alone represent a solid indicator of appendicitis but rather an inflammation<ref name=Shogilev2014 /> but the neutrophil ratio was more sensitive and specific for acute appendicitis.<ref>{{cite journal |last1=Şahbaz |first1=NA |last2=Bat |first2=O |last3=Kaya |first3=B |last4=Ulukent |first4=SC |last5=İlkgül |first5=Ö |last6=Özgün |first6=MY |last7=Akça |first7=Ö |title=The clinical value of leucocyte count and neutrophil percentage in diagnosing uncomplicated (simple) appendicitis and predicting complicated appendicitis. |journal=Ulusal Travma ve Acil Cerrahi Dergisi = Turkish Journal of Trauma & Emergency Surgery|date=November 2014 |volume=20 |issue=6 |pages=423–426 |doi=10.5505/tjtes.2014.75044 |pmid=25541921|doi-access=free }}</ref> Several routine and non-routine laboratory tests have been investigated for discriminating simple and complicated appendicitis, but their diagnostic accuracy is uncertain.<ref>{{Cite journal |last1=Sikander |first1=Binyamin |last2=Rosenberg |first2=Jacob |last3=Fonnes |first3=Siv |date=May 2023 |title=Individual biomarkers in the blood are not yet applicable in diagnosing complicated appendicitis: A scoping review |url=https://linkinghub.elsevier.com/retrieve/pii/S0735675723000839 |journal=The American Journal of Emergency Medicine |language=en |volume=67 |pages=100–107 |doi=10.1016/j.ajem.2023.02.016|pmid=36842426 }}</ref>

In children, [[Neutrophil to lymphocyte ratio|neutrophil-lymphocyte ratio (NLR)]] demonstrates a high degree of accuracy in the diagnosis of acute appendicitis and distinguishes complicated appendicitis from simple appendicitis.<ref>{{cite journal |last1=Prasetya |first1=D |last2=Rochadi |last3=Gunadi |title=Accuracy of neutrophil lymphocyte ratio for diagnosis of acute appendicitis in children: A diagnostic study. |journal=Annals of Medicine and Surgery |date=December 2019 |volume=48 |pages=35–38 |doi=10.1016/j.amsu.2019.10.013 |pmid=31687137|pmc=6820073 }}</ref> 75–78 percent of the patients have [[neutrophilia]].<ref name="Sign"/> Delta-neutrophil index (DNI) is a valuable parameter that helps in the diagnosis of histologically normal appendicitis and distinguishing between simple and complicated appendicitis.<ref>{{cite journal |last1=Shin |first1=DH |last2=Cho |first2=YS |last3=Cho |first3=GC |last4=Ahn |first4=HC |last5=Park |first5=SM |last6=Lim |first6=SW |last7=Oh |first7=YT |last8=Cho |first8=JW |last9=Park |first9=SO |last10=Lee |first10=YH |title=Delta neutrophil index as an early predictor of acute appendicitis and acute complicated appendicitis in adults. |journal=World Journal of Emergency Surgery|date=2017 |volume=12 |pages=32 |doi=10.1186/s13017-017-0140-7 |pmid=28747992 |pmc=5525197 |doi-access=free }}</ref>

A [https://medlineplus.gov/lab-tests/c-reactive-protein-crp-test/ C-reactive protein (CRP) blood test] will be ordered by the doctor to find out if there are any further causes of inflammation.<ref name="NIDDK" /> The C-reactive protein/albumin (CRP/ALB) ratio can be a reliable predictor of complicated appendicitis.<ref>Zhao, X., Yang, J. and Li, J. (2023) The predictive value of the C-reactive protein/albumin ratio in adult patients with complicated appendicitis. Journal of Laboratory Medicine. https://doi.org/10.1515/labmed-2023-0069</ref>

The [[urinalysis]] is important for ruling out a urinary tract infection as the cause of abdominal pain. The presence of more than 20 WBC per high-power field in the urine is more suggestive of a urinary tract disorder.<ref name=CDEM/>

If the patient is a female, a [[pregnancy test]] will be ordered.<ref name="NIDDK" />

===Imaging===
In children, the clinical examination is important to determine which children with abdominal pain should receive immediate surgical consultation and which should receive diagnostic imaging.<ref name="pmid17652298">{{cite journal | vauthors = Bundy DG, Byerley JS, Liles EA, Perrin EM, Katznelson J, Rice HE | title = Does this child have appendicitis? | journal = JAMA | volume = 298 | issue = 4 | pages = 438–451 | date = July 2007 | pmid = 17652298 | pmc = 2703737 | doi = 10.1001/jama.298.4.438 | author-link2 = Julie Story Byerley }}</ref> Because of the health risks of exposing children to radiation, ultrasound is the preferred first choice with CT scan being a legitimate follow-up if the ultrasound is inconclusive.<ref name="ACRfive">{{Citation |author1 = American College of Radiology |author1-link = American College of Radiology |title = Five Things Physicians and Patients Should Question |publisher = [[American College of Radiology]] |work = Choosing Wisely: an initiative of the [[ABIM Foundation]] |url = http://choosingwisely.org/wp-content/uploads/2012/04/5things_12_factsheet_Amer_Coll_Radiology.pdf |access-date = August 17, 2012 |url-status = live |archive-url = https://web.archive.org/web/20120416220509/http://choosingwisely.org/wp-content/uploads/2012/04/5things_12_factsheet_Amer_Coll_Radiology.pdf |archive-date = April 16, 2012 }}</ref><ref name="effectiveusct">{{cite journal | vauthors = Krishnamoorthi R, Ramarajan N, Wang NE, Newman B, Rubesova E, Mueller CM, Barth RA | title = Effectiveness of a staged US and CT protocol for the diagnosis of pediatric appendicitis: reducing radiation exposure in the age of ALARA | journal = Radiology | volume = 259 | issue = 1 | pages = 231–239 | date = April 2011 | pmid = 21324843 | doi = 10.1148/radiol.10100984 | doi-access =  }}</ref><ref name="appendicitischildren">{{cite journal | vauthors = Wan MJ, Krahn M, Ungar WJ, Caku E, Sung L, Medina LS, Doria AS | title = Acute appendicitis in young children: cost-effectiveness of US versus CT in diagnosis – a Markov decision analytic model | journal = Radiology | volume = 250 | issue = 2 | pages = 378–386 | date = February 2009 | pmid = 19098225 | doi = 10.1148/radiol.2502080100 | doi-access =  }}</ref> CT scan is more accurate than ultrasound for the diagnosis of appendicitis in adults and adolescents. CT scan has a [[sensitivity (tests)|sensitivity]] of 94%, [[Specificity (tests)|specificity]] of 95%. Ultrasonography had an overall [[sensitivity (tests)|sensitivity]] of 86%, a [[Specificity (tests)|specificity]] of 81%.<ref>{{cite journal | vauthors = Terasawa T, Blackmore CC, Bent S, Kohlwes RJ | title = Systematic review: computed tomography and ultrasonography to detect acute appendicitis in adults and adolescents | journal = Annals of Internal Medicine | volume = 141 | issue = 7 | pages = 537–546 | date = October 2004 | pmid = 15466771 | doi = 10.7326/0003-4819-141-7-200410050-00011 | s2cid = 46371675 }}</ref>

====Ultrasound====
[[File:SonoAppendizitis.JPG|thumb|An [[ultrasound]] image of acute appendicitis in December 2008]]
[[Abdominal ultrasonography]], preferably with [[doppler sonography]], is useful to detect appendicitis, especially in children. Ultrasound can show the free fluid collection in the right iliac fossa, along with a visible appendix with increased blood flow when using color Doppler, and noncompressibility of the appendix, as it is essentially a walled-off abscess. Other secondary sonographic signs of acute appendicitis include the presence of echogenic mesenteric fat surrounding the appendix and the acoustic shadowing of an appendicolith.<ref name="ReferenceA">{{cite journal | vauthors = Reddan T, Corness J, Mengersen K, Harden F | title = Ultrasound of pediatric appendicitis and its secondary sonographic signs: providing a more meaningful finding | journal = Journal of Medical Radiation Sciences | volume = 63 | issue = 1 | pages = 59–66 | date = March 2016 | pmid = 27087976 | pmc = 4775827 | doi = 10.1002/jmrs.154 | author3-link = Kerrie Mengersen }}</ref> In some cases (approximately 5%),<ref>{{cite journal|vauthors=Reddan T, Corness J, Mengersen K, Harden F|title=Sonographic diagnosis of acute appendicitis in children: a 3-year retrospective|journal=Sonography|volume=3|issue=3|pages=87–94|date=June 2016|doi=10.1002/sono.12068|s2cid=78306243|doi-access=free}}</ref> ultrasonography of the [[iliac fossa]] does not reveal any abnormalities despite the presence of appendicitis. This false-negative finding is especially true of early appendicitis before the appendix has become significantly distended. Also, false-negative findings are more common in adults where larger amounts of fat and bowel gas make visualizing the appendix technically difficult. Despite these limitations, sonographic imaging with experienced hands can often distinguish between appendicitis and other diseases with similar symptoms. Some of these conditions include [[inflammation]] of [[lymph nodes]] near the appendix or pain originating from other pelvic organs such as the ovaries or Fallopian tubes. Ultrasounds may be either done by the radiology department or by the emergency physician.<ref>{{cite journal |last1=Lee |first1=Sun Hwa |last2=Yun |first2=Seong Jong |title=Diagnostic performance of emergency physician-performed point-of-care ultrasonography for acute appendicitis: A meta-analysis |journal=The American Journal of Emergency Medicine |date=April 2019 |volume=37 |issue=4 |pages=696–705 |doi=10.1016/j.ajem.2018.07.025 |pmid=30017693|s2cid=51677455 }}</ref>

<gallery>
File:UOTW 45 - Ultrasound of the Week 1.webm|Ultrasound showing appendicitis and an appendicolith<ref name="UOTW45">{{cite web |date=25 April 2015 |title=UOTW #45 – Ultrasound of the Week |url=https://www.ultrasoundoftheweek.com/uotw-45/ |url-status=live |archive-url=https://web.archive.org/web/20170509131322/https://www.ultrasoundoftheweek.com/uotw-45/ |archive-date=9 May 2017 |website=Ultrasound of the Week}}</ref>
File:UOTW 45 - Ultrasound of the Week 3.jpg|Ultrasound showing appendicitis and an appendicolith<ref name=UOTW45/>
File:Ultrasonography of a normal appendix, annotated.jpg|Ultrasound of a normal appendix for comparison
File:Ultrasonography of a normal appendix without and with compression.jpg|A normal appendix without and with compression. Absence of compressibility indicates appendicitis.<ref name="ReferenceA"/>
</gallery>

====Computed tomography====
[[File:CAT scan demonstrating acute appendicitis.jpg|thumb|A CT scan demonstrating acute appendicitis (note the appendix has a diameter of 17.1 mm and there is surrounding fat stranding)]]
[[File:X-ray showing fecalith which has caused appendicitis.jpg|thumb|A [[fecalith]] marked by the arrow that has resulted in acute appendicitis.]]

Where it is readily available, [[computed tomography]] (CT) has become frequently used, especially in people whose diagnosis is not obvious on history and physical examination. Although some concerns about interpretation are identified, a 2019 Cochrane review found that the sensitivity and specificity of CT for the diagnosis of acute appendicitis in adults was high.<ref>{{Cite journal|last1=Rud|first1=Bo|last2=Vejborg|first2=Thomas S.|last3=Rappeport|first3=Eli D.|last4=Reitsma|first4=Johannes B.|last5=Wille-Jørgensen|first5=Peer|date=19 November 2019|title=Computed tomography for diagnosis of acute appendicitis in adults|journal=The Cochrane Database of Systematic Reviews|volume=2019|issue=11|doi=10.1002/14651858.CD009977.pub2|issn=1469-493X|pmc=6953397|pmid=31743429}}</ref> Concerns about radiation tend to limit use of CT in pregnant women and in children, especially with the increasingly widespread usage of MRI.<ref>{{cite journal | vauthors = Kim Y, Kang G, Moon SB | title = Increasing utilization of abdominal CT in the Emergency Department of a secondary care center: does it produce better outcomes in caring for pediatric surgical patients? | journal = Annals of Surgical Treatment and Research | volume = 87 | issue = 5 | pages = 239–244 | date = November 2014 | pmid = 25368849 | pmc = 4217253 | doi = 10.4174/astr.2014.87.5.239 }}</ref><ref>{{cite journal | vauthors = Liu B, Ramalho M, AlObaidy M, Busireddy KK, Altun E, Kalubowila J, Semelka RC | title = Gastrointestinal imaging-practical magnetic resonance imaging approach | journal = World Journal of Radiology | volume = 6 | issue = 8 | pages = 544–566 | date = August 2014 | pmid = 25170393 | pmc = 4147436 | doi = 10.4329/wjr.v6.i8.544 | doi-access = free }}</ref>

The accurate diagnosis of appendicitis is multi-tiered, with the size of the appendix having the strongest [[positive predictive value]], while indirect features can either increase or decrease sensitivity and specificity. A size of over 6&nbsp;mm is both 95% sensitive and specific for appendicitis.<ref>{{cite journal | vauthors = Garcia K, Hernanz-Schulman M, Bennett DL, Morrow SE, Yu C, Kan JH | title = Suspected appendicitis in children: diagnostic importance of normal abdominopelvic CT findings with nonvisualized appendix | journal = Radiology | volume = 250 | issue = 2 | pages = 531–537 | date = February 2009 | pmid = 19188320 | doi = 10.1148/radiol.2502080624 | doi-access =  }}</ref>

However, because the appendix can be filled with fecal material, causing intraluminal distention, this criterion has shown limited utility in more recent meta-analyses.<ref name="plumpy1">{{cite journal | vauthors = Doria AS, Moineddin R, Kellenberger CJ, Epelman M, Beyene J, Schuh S, Babyn PS, Dick PT | title = US or CT for Diagnosis of Appendicitis in Children and Adults? A Meta-Analysis | journal = Radiology | volume = 241 | issue = 1 | pages = 83–94 | date = October 2006 | pmid = 16928974 | doi = 10.1148/radiol.2411050913 }}</ref> This is as opposed to ultrasound, in which the wall of the appendix can be more easily distinguished from intraluminal feces. In such scenarios, ancillary features such as increased wall enhancement as compared to adjacent bowel and inflammation of the surrounding fat, or fat stranding, can be supportive of the diagnosis. However, their absence does not preclude it. In severe cases with perforation, an adjacent [[phlegmon]] or [[abscess]] can be seen. Dense fluid layering in the pelvis can also result, related to either [[pus]] or [[feces|enteric spillage]]. When patients are thin or younger, the relative absence of fat can make the appendix and surrounding fat stranding difficult to see.<ref name="plumpy1"/>

====Magnetic resonance imaging====
[[Magnetic resonance imaging]] (MRI) use has become increasingly common for diagnosis of appendicitis in children and pregnant patients due to the radiation dosage that, while of nearly negligible risk in healthy adults, can be harmful to children or the developing baby.<ref>{{Cite journal |last1=D'Souza |first1=Nigel |last2=Hicks |first2=Georgina |last3=Beable |first3=Richard |last4=Higginson |first4=Antony |last5=Rud |first5=Bo |date=2021-12-14 |editor-last=Cochrane Colorectal Group |title=Magnetic resonance imaging (MRI) for diagnosis of acute appendicitis |journal=Cochrane Database of Systematic Reviews |language=en |volume=2021 |issue=12 |pages=CD012028 |doi=10.1002/14651858.CD012028.pub2 |pmc=8670723 |pmid=34905621}}</ref> In pregnancy, it is more useful during the second and third trimester, particularly as the enlargening uterus displaces the appendix, making it difficult to find by ultrasound. The periappendiceal stranding that is reflected on CT by fat stranding on MRI appears as an increased fluid signal on T2 weighted sequences. First-trimester pregnancies are usually not candidates for MRI, as the fetus is still undergoing [[organogenesis]], and there are no long-term studies to date regarding its potential risks or side effects.<ref>{{cite journal | vauthors = Burke LM, Bashir MR, Miller FH, Siegelman ES, Brown M, Alobaidy M, Jaffe TA, Hussain SM, Palmer SL, Garon BL, Oto A, Reinhold C, Ascher SM, Demulder DK, Thomas S, Best S, Borer J, Zhao K, Pinel-Giroux F, De Oliveira I, Resende D, Semelka RC | title = Magnetic resonance imaging of acute appendicitis in pregnancy: a 5-year multi-institutional study | journal = American Journal of Obstetrics and Gynecology | volume = 213 | issue = 5 | pages = 693.e1–6 | date = November 2015 | pmid = 26215327 | doi = 10.1016/j.ajog.2015.07.026 }}</ref>

====X-ray====
[[File:AppendicolithPlainXray.png|thumb|Appendicolith as seen on plain X-ray]]
In general, plain abdominal radiography (PAR) is not useful in making the diagnosis of appendicitis and should not be routinely obtained from a person being evaluated for appendicitis.<ref>{{cite journal | vauthors = Rao PM, Rhea JT, Rao JA, Conn AK | title = Plain abdominal radiography in clinically suspected appendicitis: diagnostic yield, resource use, and comparison with CT | journal = The American Journal of Emergency Medicine | volume = 17 | issue = 4 | pages = 325–328 | date = July 1999 | pmid = 10452424 | doi = 10.1016/S0735-6757(99)90077-3 }}</ref><ref>{{cite journal | vauthors = Boleslawski E, Panis Y, Benoist S, Denet C, Mariani P, Valleur P | title = Plain abdominal radiography as a routine procedure for acute abdominal pain of the right lower quadrant: prospective evaluation | journal = World Journal of Surgery | volume = 23 | issue = 3 | pages = 262–264 | date = March 1999 | pmid = 9933697 | doi = 10.1007/pl00013181 | s2cid = 23733164 }}</ref> Plain abdominal films may be useful for the detection of [[ureter]]al [[calculus (medicine)|calculi]], [[small bowel obstruction]], or [[perforated ulcer]], but these conditions are rarely confused with appendicitis.<ref name=Sabiston>[http://www.uptomed.ir/Digimed.ir/sabiston-2009/Sabiston_2009/HTML/473.htm APPENDICITIS from Townsend: Sabiston Textbook of Surgery on MD Consult<!-- Bot generated title -->] {{webarchive |url=https://web.archive.org/web/20131203014844/http://www.uptomed.ir/Digimed.ir/sabiston-2009/Sabiston_2009/HTML/473.htm |date=December 3, 2013 }}</ref> An opaque [[fecalith]] can be identified in the right lower quadrant in fewer than 5% of people being evaluated for appendicitis.<ref name=CDEM/> A [[barium enema]] has proven to be a poor diagnostic tool for appendicitis. While failure of the appendix to fill during a barium enema has been associated with appendicitis, up to 20% of normal appendices do not fill.<ref name=Sabiston/>

===Scoring systems===
Several scoring systems have been developed to try to identify people who are likely to have appendicitis.<ref>{{Cite journal |last1=Bahta |first1=Nadir Noureldin Abdella |last2=Rosenberg |first2=Jacob |last3=Fonnes |first3=Siv |date=May 2023 |title=Many diagnostic tools for appendicitis: a scoping review |url=https://pubmed.ncbi.nlm.nih.gov/36735050 |journal=Surgical Endoscopy |volume=37 |issue=5 |pages=3419–3429 |doi=10.1007/s00464-023-09890-2 |issn=1432-2218 |pmid=36735050}}</ref> The performance of scores such as the [[Alvarado score]] and the Pediatric Appendicitis Score, however, are variable.<ref name=Kul2013>{{cite journal | vauthors = Kulik DM, Uleryk EM, Maguire JL | title = Does this child have appendicitis? A systematic review of clinical prediction rules for children with acute abdominal pain | journal = Journal of Clinical Epidemiology | volume = 66 | issue = 1 | pages = 95–104 | date = January 2013 | pmid = 23177898 | doi = 10.1016/j.jclinepi.2012.09.004 }}</ref>

The Alvarado score is the most known scoring system. A score below 5 suggests against a diagnosis of appendicitis, whereas a score of 7 or more is predictive of acute appendicitis. In a person with an equivocal score of 5 or 6, a CT scan or ultrasound exam may be used to reduce the rate of negative appendectomy.

{| class="wikitable" style="margin-left:15px; text-align:center"
|+ Alvarado score
|-
| Migratory right [[iliac fossa]] pain
| 1 point
|-
| [[Anorexia (symptom)|Anorexia]]
| 1 point
|-
| [[Nausea]] and [[vomiting]]
| 1 point
|-
|Right iliac fossa [[tenderness (medicine)|tenderness]]
|2 points
|-
|[[Blumberg's sign|Rebound abdominal tenderness]]
|1 point
|-
|[[Fever]]
|1 point
|-
| High white blood cell count ([[leukocytosis]])
|2 points
|-
|Shift to left (segmented [[neutrophils]])
|1 point
|-
!Total score
!10 points
|}

===Pathology===
Even for clinically certain appendicitis, routine [[histopathology]] examination of appendectomy specimens is of value for identifying unsuspected pathologies requiring further postoperative management.<ref name="Abd Al-Fatah2017">{{cite journal|last1=Abd Al-Fatah|first1=Mohamed|title=Importance of histopathological evaluation of appendectomy specimens|journal=Al-Azhar Assiut Medical Journal|volume=15|issue=2|year=2017|pages=97|issn=1687-1693|doi=10.4103/AZMJ.AZMJ_19_17|s2cid=202550141|doi-access=free}}</ref> No sign of appendicitis in specimens, negative appendectomy, varies but has been estimated to occur in 13% of specimens.<ref>{{Cite journal |last1=Henriksen |first1=Siri R. |last2=Christophersen |first2=Camilla |last3=Rosenberg |first3=Jacob |last4=Fonnes |first4=Siv |date=2023-05-23 |title=Varying negative appendectomy rates after laparoscopic appendectomy: a systematic review and meta-analysis |url=https://link.springer.com/10.1007/s00423-023-02935-z |journal=Langenbeck's Archives of Surgery |language=en |volume=408 |issue=1 |page=205 |doi=10.1007/s00423-023-02935-z |pmid=37219616 |issn=1435-2451}}</ref> Notably, [[appendix cancer]] is found incidentally in about 1% of appendectomy specimens.<ref name="LeeChoi2011">{{cite journal|last1=Lee|first1=Won-Suk|last2=Choi|first2=Sang Tae|last3=Lee|first3=Jung Nam|last4=Kim|first4=Keon Kug|last5=Park|first5=Yeon Ho|last6=Baek|first6=Jeong Heum|title=A retrospective clinicopathological analysis of appendiceal tumors from 3,744 appendectomies: a single-institution study|journal=International Journal of Colorectal Disease|volume=26|issue=5|year=2011|pages=617–621|issn=0179-1958|doi=10.1007/s00384-010-1124-1|pmid=21234578|s2cid=12566272}}</ref><ref>{{Cite journal |last1=Henriksen |first1=Siri Rønholdt |last2=Rosenberg |first2=Jacob |last3=Fonnes |first3=Siv |date=2023 |title=Other Pathologies Were Rarely Reported after Laparoscopic Surgery for Suspected Appendicitis: A Systematic Review and Meta-Analysis |url=https://karger.com/DSU/article/doi/10.1159/000531283 |journal=Digestive Surgery |language=en |volume=40 |issue=3–4 |pages=91–99 |doi=10.1159/000531283 |pmid=37463567 |issn=0253-4886}}</ref>

Pathology diagnosis of appendicitis can be made by detecting a [[neutrophil]]ic infiltrate of the [[muscularis propria]].

Periappendicitis (inflammation of tissues around the appendix) is often found in conjunction with other abdominal pathology.<ref name=pmid2349982>{{cite journal | vauthors = Fink AS, Kosakowski CA, Hiatt JR, Cochran AJ | title = Periappendicitis is a significant clinical finding | journal = American Journal of Surgery | volume = 159 | issue = 6 | pages = 564–568 | date = June 1990 | pmid = 2349982 | doi = 10.1016/S0002-9610(06)80067-X }}</ref>

<gallery>
File:Appendicitis - low mag.jpg|[[Micrograph]] of appendicitis and periappendicitis. [[H&E stain]]
File:Acute appendicitis High Power.jpg|Micrograph of appendicitis showing neutrophils in the muscularis propria. H&E stain
File:Acute suppurative appendicitis with perforation.jpg|Acute suppurative appendicitis with perforation (at right). H&E stain
</gallery>

{|class=wikitable
|+ Classification of acute appendicitis based on [[gross pathology]] and [[light microscopy]] characteristics<ref name="Carr2000">{{cite journal|last1=Carr|first1=Norman J.|title=The pathology of acute appendicitis|journal=Annals of Diagnostic Pathology|volume=4|issue=1|year=2000|pages=46–58|issn=1092-9134|doi=10.1016/S1092-9134(00)90011-X|pmid=10684382}}</ref>
|-
! Pattern !! Gross pathology !! Light microscopy !! Image !! Clinical significance
|-
! Acute intraluminal inflammation
| None visible ||
* Only neutrophils in the lumen
* No ulceration or transmural inflammation
| [[File:Histopathology of acute intraluminal inflammation of the appendix.jpg|190px]]
| Probably none
|-
! Acuta mucosal inflammation
| None visible ||
* Neutrophils within the mucosa, and possibly in the submucosa
* Mucosal ulceration
|
| May be secondary to [[enteritis]].
|-
! Suppurative acute appendicitis
| May be inapparent.
* Dull mucosa
* Congested surface vessels
* Fibropurulent serosal exudate in late cases
* Dilated appendix
|
* Neutrophils in the mucosa, submucosa, and muscularis propria, potentially transmural.
* Extensive inflammation
* Commonly intramural abscesses
* Possibly vascular thrombosis
| [[File:Acute suppurative appendicitis with perforation.jpg|190px]]
| Can be presumed to be the primary cause of symptoms
|-
! Gangrenous/necrotizing appendicitis
|
* Friable wall
* Purple, green, or black color
|
* Transmural inflammation, obliterating normal histological structures
* Necrotic areas
* Extensive mucosal ulceration
| [[File:Histopathology of necrotizing appendicitis, high magnification.jpg|190px]]
| Will perforate if untreated
|-
! Periappendicitis
| May be inapparent.
* Serosa may be congested, dull, and exudative
|
* Serosal and subserosal inflammation, no further than outer muscularis propria to be called isolated
| [[File:Histopathology of periappendicitis.jpg|190px]]
| If isolated, probably secondary to other disease
|-
! Eosinophilic appendicitis
| None visible
|
* >10 eosinophils/mm<sup>2</sup> in muscularis propria.
* No changes conforming to other types of appendicitis
|
| Possibly parasitic, or eosinophilic enteritis.
|}

===Differential diagnosis===
[[File:Enlarged gallbladder with gallstone and cholecystitis.jpg|thumb|[[Coronal plane|Coronal]] [[CT scan]] of a person initially suspected of having appendicitis because of right-sided pain. The CT shows in fact an enlarged [[cholecystitis|inflamed gallbladder]] that reaches the right lower part of the abdomen.]]
Children: [[Gastroenteritis]], [[mesenteric adenitis]], [[Meckel's diverticulum|Meckel's diverticulitis]], [[intussusception (medical disorder)|intussusception]], [[Henoch–Schönlein purpura]], lobar [[pneumonia]], [[urinary tract infection]] (abdominal pain in the absence of other symptoms can occur in children with UTI), new-onset [[Crohn's disease]] or [[ulcerative colitis]], [[pancreatitis]], and abdominal trauma from [[child abuse]]; [[distal intestinal obstruction syndrome]] in children with cystic fibrosis; [[typhlitis]] in children with leukemia.

Women: A pregnancy test is important for all women of childbearing age since an [[ectopic pregnancy]] can have signs and symptoms similar to those of appendicitis. Other obstetrical/ gynecological causes of similar abdominal pain in women include [[pelvic inflammatory disease]], [[ovarian torsion]], [[menarche]], dysmenorrhea, [[endometriosis]], and [[Mittelschmerz]] (the passing of an egg in the ovaries approximately two weeks before menstruation).<ref>{{cite web | title = Pelvic inflammatory disease (PID) Symptoms; Diseases and Conditions | publisher = Mayo Clinic | url = http://www.mayoclinic.org/diseases-conditions/pelvic-inflammatory-disease/basics/symptoms/con-20022341 | access-date = 2015-04-23 | url-status = live | archive-url = https://web.archive.org/web/20150507162533/http://www.mayoclinic.org/diseases-conditions/pelvic-inflammatory-disease/basics/symptoms/con-20022341 | archive-date = 2015-05-07 }}</ref>

Men: [[testicular torsion]]

Adults: new-onset [[Crohn disease]], [[ulcerative colitis]], regional enteritis, [[cholecystitis]], [[renal colic]], perforated [[peptic ulcer]], [[pancreatitis]], [[rectus sheath hematoma]] and [[epiploic appendagitis]].

Elderly: [[diverticulitis]], intestinal obstruction, [[colon cancer|colonic carcinoma]], [[mesenteric ischemia]], leaking [[aortic aneurysm]].

The term "{{visible anchor|pseudoappendicitis}}" is used to describe a condition mimicking appendicitis.<ref name="pmid20633930">{{cite journal | vauthors = Cunha BA, Pherez FM, Durie N | title = Swine influenza (H1N1) and acute appendicitis | journal = Heart & Lung | volume = 39 | issue = 6 | pages = 544–546 | date = July 2010 | pmid = 20633930 | doi = 10.1016/j.hrtlng.2010.04.004 }}</ref> It can be associated with ''[[Yersinia enterocolitica]]''.<ref name="pmid18575909">{{cite book |title=Yersinia enterocolitica infection in diarrheal patients |journal=Eur. J. Clin. Microbiol. Infect. Dis. |volume=27 |issue=8 |pages=741–752 |date=August 2008 |isbn=978-0-9600805-6-4 |pmid=18575909 |doi=10.1007/s10096-008-0562-y |vauthors=Zheng H, Sun Y, Lin S, Mao Z, Jiang B |s2cid=23127869 }}</ref>

==Management==
Acute appendicitis<ref>{{Cite web|title=appendicitis|url=https://www.healthnsurgery.com/appendicitis-symptoms-causes-and-treatment/|url-status=live|website=health n surgery|date=15 June 2020|archive-url=https://web.archive.org/web/20201025130423/https://www.healthnsurgery.com/appendicitis-symptoms-causes-and-treatment/ |archive-date=2020-10-25 }}</ref> is typically managed by [[surgery]]. While antibiotics are safe and effective for treating uncomplicated appendicitis,<ref name="BJS paper"/><ref name=Antibiotics2012/><ref>{{cite journal | vauthors = Sallinen V, Akl EA, You JJ, Agarwal A, Shoucair S, Vandvik PO, Agoritsas T, Heels-Ansdell D, Guyatt GH, Tikkinen KA | title = Meta-analysis of antibiotics versus appendicectomy for non-perforated acute appendicitis | journal = The British Journal of Surgery | volume = 103 | issue = 6 | pages = 656–667 | date = May 2016 | pmid = 26990957 | pmc = 5069642 | doi = 10.1002/bjs.10147 }}</ref> 31% of people had a recurrence within a year and required an eventual appendectomy.<ref name="ReferenceB"/> Antibiotics are less effective if an [[appendicolith]] is present.<ref>{{cite journal | vauthors = Huang L, Yin Y, Yang L, Wang C, Li Y, Zhou Z | title = Comparison of Antibiotic Therapy and Appendectomy for Acute Uncomplicated Appendicitis in Children: A Meta-analysis | journal = JAMA Pediatrics | volume = 171 | issue = 5 | pages = 426–434 | date = May 2017 | pmid = 28346589 | pmc = 5470362 | doi = 10.1001/jamapediatrics.2017.0057 }}</ref> While 51% of patients who were treated with antibiotics did not need an appendectomy three years after treatment,<ref>{{Cite web |date=2024-05-06 |title=Comparing Surgery versus Antibiotics for Treating Adults with Uncomplicated Appendicitis - Evidence Update for Clinicians {{!}} PCORI |url=https://www.pcori.org/evidence-updates/comparing-surgery-versus-antibiotics-treating-adults-uncomplicated-appendicitis |access-date=2024-05-23 |website=www.pcori.org |language=en}}</ref> the cost effectiveness of surgery versus antibiotics is unclear<ref>{{cite journal | vauthors = Georgiou R, Eaton S, Stanton MP, Pierro A, Hall NJ | title = Efficacy and Safety of Nonoperative Treatment for Acute Appendicitis: A Meta-analysis | journal = Pediatrics | volume = 139 | issue = 3 | pages = e20163003 | date = March 2017 | pmid = 28213607 | doi = 10.1542/peds.2016-3003 | s2cid = 2292989 | url = http://discovery.ucl.ac.uk/1529248/1/Manuscript%20Pediatrics%20R1_with_figures.pdf | doi-access = free }}</ref>

Using antibiotics to prevent potential postoperative complications in emergency appendectomy procedures is recommended, and the antibiotics are effective when given to a person before, during, or after surgery.<ref>{{cite journal | vauthors = Andersen BR, Kallehave FL, Andersen HK | title = Antibiotics versus placebo for prevention of postoperative infection after appendicectomy | journal = The Cochrane Database of Systematic Reviews | issue = 3 | pages = CD001439 | date = July 2005 | volume = 2009 | pmid = 16034862 | doi = 10.1002/14651858.CD001439.pub2 | pmc = 8407323 }}</ref>

===Pain===
Pain medications (such as [[morphine]]) do not appear to affect the accuracy of the clinical diagnosis of appendicitis and therefore should be given early in the patient's care.<ref name=And2008>{{cite journal | vauthors = Anderson M, Collins E | title = Analgesia for children with acute abdominal pain and diagnostic accuracy | journal = Archives of Disease in Childhood | volume = 93 | issue = 11 | pages = 995–997 | date = November 2008 | pmid = 18305071 | doi = 10.1136/adc.2008.137174 | s2cid = 219246210 | url = http://www.bestbets.org/bets/bet.php?id=1404 | url-status = live | archive-url = https://web.archive.org/web/20130517121005/http://www.bestbets.org/bets/bet.php?id=1404 | archive-date = 2013-05-17 }}</ref> Historically there were concerns among some general surgeons that analgesics would affect the clinical exam in children, and some recommended that they not be given until the surgeon was able to examine the person.<ref name=And2008/>

===Surgery===
{{see also|Appendectomy}}
[[File:Apendixexternalview.jpg|thumb|Inflamed appendix removal by open surgery]]
[[File:Appendix-Entfernung.jpg|thumb|Laparoscopic appendectomy.]]
[[File:Lap apendix.jpg|thumb|Laparoscopic view of a phlegmonous cecal appendix with fibrinous plaques, located in the right iliac fossa.]]
The [[surgery|surgical]] procedure for the removal of the appendix is called an [[appendectomy]]. A negative appendectomy constitutes the removal of a normal appendix with no sign of inflammation in [[histopathology]] examination. The prevalence of negative appendectomy varies but has been estimated to 13%.<ref>{{Cite journal |last1=Henriksen |first1=Siri R. |last2=Christophersen |first2=Camilla |last3=Rosenberg |first3=Jacob |last4=Fonnes |first4=Siv |date=2023-05-23 |title=Varying negative appendectomy rates after laparoscopic appendectomy: a systematic review and meta-analysis |url=https://link.springer.com/10.1007/s00423-023-02935-z |journal=Langenbeck's Archives of Surgery |language=en |volume=408 |issue=1 |page=205 |doi=10.1007/s00423-023-02935-z |pmid=37219616 |issn=1435-2451}}</ref> Appendectomy can be performed through open or laparoscopic surgery. Laparoscopic appendectomy has several advantages over open appendectomy as an intervention for acute appendicitis.<ref>{{cite journal | vauthors = Jaschinski T, Mosch CG, Eikermann M, Neugebauer EA, Sauerland S | title = Laparoscopic versus open surgery for suspected appendicitis | journal = The Cochrane Database of Systematic Reviews | volume = 2018 | pages = CD001546 | date = November 2018 | issue = 11 | pmid = 30484855 | pmc = 6517145 | doi = 10.1002/14651858.CD001546.pub4 }}</ref>

====Open appendectomy====
For over a century, laparotomy (open appendectomy) was the standard treatment for acute appendicitis.<ref>{{cite journal | vauthors = Berry J, Malt RA | title = Appendicitis near its centenary | journal = Annals of Surgery | volume = 200 | issue = 5 | pages = 567–575 | date = November 1984 | pmid = 6385879 | pmc = 1250537 | doi = 10.1097/00000658-198411000-00002 }}</ref> This procedure consists of the removal of the infected appendix through a single large incision in the lower right area of the abdomen.<ref>{{cite web |url=http://digestive.niddk.nih.gov/ddiseases/pubs/appendicitis/ |title=Appendicitis |work=National Institute of Diabetes and Digestive and Kidney Diseases |publisher=U.S. Department of Health and Human Services |access-date=2010-02-01 |url-status=dead |archive-url=https://web.archive.org/web/20100201095103/http://digestive.niddk.nih.gov/ddiseases/pubs/appendicitis/ |archive-date=2010-02-01 }}</ref> The incision in a laparotomy is usually {{convert|2|to|3|in}} long.

During an open appendectomy, the person with suspected appendicitis is placed under general [[anesthesia]] to keep the muscles completely relaxed and to keep the person unconscious. The incision is two to three inches (76&nbsp;mm) long, and it is made in the right lower abdomen, several inches above the [[hip bone]]. Once the incision opens the abdomen cavity, and the appendix is identified, the [[surgeon]] removes the infected tissue and cuts the appendix from the surrounding tissue. After careful and close inspection of the infected area, and ensuring there are no signs that surrounding tissues are damaged or infected. In case of complicated appendicitis managed by an emergency open appendectomy, abdominal drainage (a temporary tube from the abdomen to the outside to avoid abscess formation) may be inserted, but this may increase the hospital stay.<ref>{{cite journal|vauthors=Li Z, Li Z, Zhao L, Cheng Y, Cheng N, Deng Y|date=August 2021|title=Abdominal drainage to prevent intra-peritoneal abscess after appendectomy for complicated appendicitis|journal=The Cochrane Database of Systematic Reviews|volume=2021|issue=8|pages=CD010168|doi=10.1002/14651858.CD010168.pub4|pmid=34402522|pmc=8407456}}</ref>{{Update inline|reason=Updated version https://www.ncbi.nlm.nih.gov/pubmed/34402522|date = October 2021}} The surgeon will start closing the incision. This means sewing the muscles and using [[surgical staple]]s or [[surgical suture|stitches]] to close the skin up. To prevent infections, the incision is covered with a [[Dressing (medical)|sterile bandage]] or surgical adhesive.

====Laparoscopic appendectomy====
Laparoscopic appendectomy was introduced in 1983 and has become an increasingly prevalent intervention for acute appendicitis.<ref>{{cite journal | vauthors = Semm K | title = Endoscopic appendectomy | journal = Endoscopy | volume = 15 | issue = 2 | pages = 59–64 | date = March 1983 | pmid = 6221925 | doi = 10.1055/s-2007-1021466 | s2cid = 45763958 }}</ref> This surgical procedure consists of making three to four incisions in the abdomen, each {{convert|0.25|to|0.5|in|mm}} long. This type of appendectomy is made by inserting a special surgical tool called a laparoscope into one of the incisions. The laparoscope is connected to a monitor outside the person's body, and it is designed to help the surgeon inspect the infected area in the abdomen. The other two incisions are made for the specific removal of the appendix by using [[surgical instrument]]s. Laparoscopic surgery requires [[general anesthesia]], and it can last up to two hours. Laparoscopic appendectomy has several advantages over open appendectomy, including a shorter post-operative recovery, less post-operative pain, and a lower superficial surgical site infection rate. However, the occurrence of an intra-abdominal abscess is almost three times more prevalent in laparoscopic appendectomy than open appendectomy.<ref>{{cite journal | vauthors = Siewert B, Raptopoulos V, Liu SI, Hodin RA, Davis RB, Rosen MP | title = CT predictors of failed laparoscopic appendectomy | journal = Radiology | volume = 229 | issue = 2 | pages = 415–420 | date = November 2003 | pmid = 14595145 | doi = 10.1148/radiol.2292020825 }}</ref>

==== Laparoscopic-assisted transumbilical appendectomy ====
In pediatric patients, the high mobility of the cecum allows externalization of the appendix through the umbilicus, and the entire procedure can be performed with a single incision. Laparoscopic-assisted transumbilical appendectomy is a relatively recent technique but with a long published series and very good surgical and aesthetic results.<ref>{{Cite journal |last1=Sekioka |first1=Akinori |last2=Takahashi |first2=Toshiaki |last3=Yamoto |first3=Masaya |last4=Miyake |first4=Hiromu |last5=Fukumoto |first5=Koji |last6=Nakaya |first6=Kengo |last7=Nomura |first7=Akiyoshi |last8=Yamada |first8=Yutaka |last9=Urushihara |first9=Naoto |date=December 2018 |title=Outcomes of Transumbilical Laparoscopic-Assisted Appendectomy and Conventional Laparoscopic Appendectomy for Acute Pediatric Appendicitis in a Single Institution |url=https://pubmed.ncbi.nlm.nih.gov/30088968 |journal=Journal of Laparoendoscopic & Advanced Surgical Techniques. Part A |volume=28 |issue=12 |pages=1548–1552 |doi=10.1089/lap.2018.0306 |issn=1557-9034 |pmid=30088968|s2cid=51941735 }}</ref>

====Pre-surgery====
The treatment begins by [[Nil per os|keeping the person who will be having surgery from eating or drinking]] for a given period, usually overnight. An [[Intravenous therapy|intravenous drip]] is used to hydrate the person who will be having surgery. [[Antibiotic]]s given intravenously such as [[cefuroxime]] and [[metronidazole]] may be administered early to help kill bacteria and thus reduce the spread of infection in the abdomen and postoperative complications in the abdomen or wound. Equivocal cases may become more difficult to assess with antibiotic treatment and benefit from serial examinations. If the stomach is empty (no food in the past six hours), general anaesthesia is usually used. Otherwise, [[spinal anaesthesia]] may be used.

Once the decision to perform an [[appendectomy]] has been made, the preparation procedure takes approximately one to two hours. Meanwhile, the surgeon will explain the surgery procedure and will present the risks that must be considered when performing an appendectomy. (With all surgeries there are risks that must be evaluated before performing the procedures.) The risks are different depending on the state of the appendix. If the appendix has not ruptured, the complication rate is only about 3% but if the appendix has ruptured, the complication rate rises to almost 59%.<ref>{{cite encyclopedia |url=http://www.surgeryencyclopedia.com/A-Ce/Appendectomy.html |title=Appendicitis |encyclopedia=Encyclopedia of Surgery |access-date=2010-02-01 |url-status=live |archive-url=https://web.archive.org/web/20100209031325/http://www.surgeryencyclopedia.com/A-Ce/Appendectomy.html |archive-date=2010-02-09 }}</ref> The most usual complications that can occur are pneumonia, [[hernia]] of the incision, [[thrombophlebitis]], bleeding and [[adhesion (medicine)|adhesions]]. Evidence indicates that a delay in obtaining surgery after admission results in no measurable difference in outcomes to the person with appendicitis.<ref>{{cite news |url=http://www.cbc.ca/news/technology/emergency-appendix-surgery-can-wait-mds-1.921386 |work=CBC News |title='Emergency' appendix surgery can wait: MDs |date=2010-09-21 |url-status=live |archive-url=https://web.archive.org/web/20160630014355/http://www.cbc.ca/news/technology/emergency-appendix-surgery-can-wait-mds-1.921386 |archive-date=2016-06-30 }}</ref><ref>{{cite journal | vauthors = Ingraham AM, Cohen ME, Bilimoria KY, Ko CY, Hall BL, Russell TR, Nathens AB | title = Effect of delay to operation on outcomes in adults with acute appendicitis | journal = Archives of Surgery | volume = 145 | issue = 9 | pages = 886–892 | date = September 2010 | pmid = 20855760 | doi = 10.1001/archsurg.2010.184 | quote = Delay of appendectomy for acute appendicitis in adults does not appear to adversely affect 30-day outcomes. | doi-access =  }}</ref> Most patients undergo emergency surgery, but delayed surgery (interval appendectomy) has been investigated for certain patients.<ref name=":1">{{Cite journal |last1=Zhou |first1=Shiyi |last2=Cheng |first2=Yao |last3=Cheng |first3=Nansheng |last4=Gong |first4=Jianping |last5=Tu |first5=Bing |date=2024-05-02 |editor-last=Cochrane Colorectal Group |title=Early versus delayed appendicectomy for appendiceal phlegmon or abscess |journal=Cochrane Database of Systematic Reviews |language=en |volume=2024 |issue=5 |pages=CD011670 |doi=10.1002/14651858.CD011670.pub3 |pmc=11064883 |pmid=38695830}}</ref> Delaying surgery for weeks may increase the risk of intra-abdominal abscess in patients suffering from appendicitis and presenting with an appendiceal mass (e.g., [[phlegmon]] or [[abscess]]).<ref name=":1" /> The harms and benefits of delaying surgery for other complications are uncertain.<ref name=":1" /> 
[[File:Scarlapappendix.jpg|thumb|Laparoscopic-assisted transumbilical appendectomy scar on a pediatric patient. Anesthetic result one month after surgery.]]
The surgeon will explain how long the recovery process should take. Abdomen hair is usually removed to avoid complications that may appear regarding the incision.

In most cases, patients going in for surgery experience nausea or vomiting that require medication before surgery. Antibiotics, along with pain medication, may be administered before appendectomies.

====After surgery====
[[File:Stitches post appendicitis surgery.jpg|thumb|The [[surgical suture|stitches]] the day after having the appendix removed by laparoscopic surgery]]
Hospital lengths of stay typically range from a few hours to a few days but can be a few weeks if complications occur. The recovery process may vary depending on the severity of the condition: if the appendix had ruptured or not before surgery. Appendix surgery recovery is generally much faster if the appendix does not rupture.<ref>[http://appendixsurgery.net Appendicitis surgery, removal and reco very]. Retrieved on 2010-02-01. {{webarchive|url=https://web.archive.org/web/20100111221304/http://appendixsurgery.net/|date=January 11, 2010}}.</ref> It is important that people undergoing surgery respect their doctor's advice and limit their physical activity so the tissues can heal. Recovery after an appendectomy may not require diet changes or a lifestyle change.

The length of hospital stays for appendicitis varies on the severity of the condition. A study from the United States found that in 2010, the average appendicitis hospital stay was 1.8 days. For stays where the person's appendix had ruptured, the average length of stay was 5.2 days.<ref name=Barrett2013/>

After surgery, the patient will be transferred to a [[postanesthesia care unit]], so their vital signs can be closely monitored to detect anesthesia- or surgery-related complications. Pain medication may be administered if necessary. After patients are completely awake, they are moved to a hospital room to recover. Most individuals will be offered clear liquids the day after the surgery, then progress to a regular diet when the intestines start to function correctly. Patients are recommended to sit on the edge of the bed and walk short distances several times a day. Moving is mandatory, and pain medication may be given if necessary. Full recovery from appendectomies takes about four to six weeks but can be prolonged to up to eight weeks if the appendix has ruptured.<ref><p> <a href="https://aeliussurgery.com.sg/conditions/appendicitis-surgery-in-singapore/">Appendicitis surgery in Singapore</a>
is commonly performed using laparoscopic techniques to ensure faster recovery and minimal scarring.</p></ref>

==Prognosis==
Most people with appendicitis recover quickly after surgical treatment, but complications can occur if treatment is delayed or if [[peritonitis]] occurs. Recovery time depends on age, condition, complications, and other circumstances, including the amount of alcohol consumption, but usually is between 10 and 28 days. For young children (around ten years old), the recovery takes three weeks.

The possibility of peritonitis is the reason why acute appendicitis warrants rapid evaluation and treatment. People with suspected appendicitis may have to undergo a [[medical evacuation]]. Appendectomies have occasionally been performed in emergency conditions (i.e., not in a proper hospital) when a timely medical evacuation was impossible.

Typical acute appendicitis responds quickly to appendectomy and occasionally will resolve spontaneously. If appendicitis resolves spontaneously, it remains controversial whether an elective interval appendectomy should be performed to prevent a recurrent episode of appendicitis. Atypical appendicitis (associated with suppurative appendicitis) is more challenging to diagnose and is more apt to be complicated even when operated early. In either condition, prompt diagnosis and appendectomy yield the best results with full recovery in two to four weeks usually. Mortality and severe complications are unusual but do occur, especially if peritonitis persists and is untreated.

Another entity known as the appendicular lump is talked about. It happens when the appendix is not removed early during infection, and the omentum and intestine adhere to it, forming a palpable lump. During this period, surgery is risky unless there is pus formation evident by fever and toxicity or by ultrasound. Medical management treats the condition.

An unusual complication of an appendectomy is "stump appendicitis": inflammation occurs in the remnant appendiceal stump left after a prior incomplete appendectomy.<ref name="pmid16536249">{{cite journal | vauthors = Liang MK, Lo HG, Marks JL | title = Stump appendicitis: a comprehensive review of literature | journal = The American Surgeon | volume = 72 | issue = 2 | pages = 162–166 | date = February 2006 | pmid = 16536249 | doi =  10.1177/000313480607200214| s2cid = 37041386 | doi-access = free }}</ref> Stump appendicitis can occur months to years after initial appendectomy and can be identified with imaging modalities such as ultrasound.<ref>{{cite journal | vauthors = Reddan T, Corness J, Powell J, Harden F, Mengersen K |author5-link= Kerrie Mengersen |title=Stumped? It could be stump appendicitis |journal= Sonography |date=2016 |doi=10.1002/sono.12098 |volume=4 |pages=36–39 |doi-access=free }}</ref>

==History==
The history of appendicitis traces back to ancient medical texts, though its clear clinical understanding emerged in the 19th century. Berengario da Carpi provided the first recorded description of the appendix in the 16th century, followed by [[Andreas Vesalius]] and [[Gabriele Falloppio]]. Clinical understanding progressed in the 18th and 19th centuries, marked by Lorenz Heister's autopsy findings, Claudius Aymand's surgical intervention, and J. Mestivier's operation for appendicitis. Prior to the use of the term ''appendicitis'', it was described with terms including ''perityphlitis'', ''typhlitis'', ''paratyphlitis'', and ''extra-peritoneal abscess of the right iliac fossa''.<ref>{{Cite journal |last1=Krzyzak |first1=Michael |last2=Mulrooney |first2=Stephen M. |last3=Krzyzak |first3=Michael |last4=Mulrooney |first4=Stephen M. |date=2020-06-11 |title=Acute Appendicitis Review: Background, Epidemiology, Diagnosis, and Treatment |journal=Cureus |language=en |volume=12 |issue=6 |pages=e8562 |doi=10.7759/cureus.8562 |doi-access=free |pmid=32670699 |issn=2168-8184|pmc=7358958 }}</ref> The term "appendicitis" was coined by the American physician [[Reginald Heber Fitz]] in 1886, leading to standardized diagnosis and treatment, including Charles McBurney's identification of McBurney's point. Modern appendectomy techniques evolved in the early 20th century, coinciding with advancements in pathology, notably demonstrated by Ludwig Aschoff in 1908.<ref name=RONDELLI2017>{{cite web|title=The early days in the history of appendectomy|url=https://hekint.org/2017/01/22/the-early-days-in-the-history-of-appendectomy/|website=Hektoen International|date=22 January 2017|author=Rondelli D}}</ref><ref>{{Cite journal|vauthors=Fitz RH |title=Perforating inflammation of the vermiform appendix with special reference to its early diagnosis and treatment |journal=American Journal of the Medical Sciences |issue=92 |pages=321–346 |year=1886}}</ref>

==Epidemiology==

[[File:Appendicitis world map-Deaths per million persons-WHO2012.svg|thumb|upright=1.3|Appendicitis deaths per million persons in 2012
{{Div col|small=yes|colwidth=10em}}
{{legend|#ffff20|0}}
{{legend|#ffe820|1}}
{{legend|#ffc020|2}}
{{legend|#ffa020|3}}
{{legend|#ff9a20|4}}
{{legend|#f08015|5–7}}
{{legend|#e06815|8–11}}
{{legend|#d85010|12–33}}
{{legend|#d02010|34–77}}
{{div col end}}]]
[[File:Appendicitis world map - DALY - WHO2004.svg|thumb|upright=1.3|[[Disability-adjusted life year]] for appendicitis per 100,000&nbsp;inhabitants in 2004.<ref>{{cite web|url=https://www.who.int/healthinfo/global_burden_disease/estimates_country/en/index.html |title=WHO Disease and injury country estimates |year=2009 |work=[[World Health Organization]] |access-date=Nov 11, 2009| archive-url= https://web.archive.org/web/20201111215234/https://www.who.int/healthinfo/global_burden_disease/estimates_country/en/ |archive-date= 11 November 2020 |url-status=live}}</ref>
{{Div col|small=yes|colwidth=10em}}
{{legend|#b3b3b3|no data}}
{{legend|#ffff65|less than 2.5}}
{{legend|#fff200|2.5–5}}
{{legend|#ffdc00|5–7.5}}
{{legend|#ffc600|7.5–10}}
{{legend|#ffb000|10–12.5}}
{{legend|#ff9a00|12.5–15}}
{{legend|#ff8400|15–17.5}}
{{legend|#ff6e00|17.5–20}}
{{legend|#ff5800|20–22.5}}
{{legend|#ff4200|22.5–25}}
{{legend|#ff2c00|25–27.5}}
{{legend|#cb0000|more than 27.5}}
{{div col end}}]]

Appendicitis is most common between the ages of 5 and 40.<ref>{{cite journal | vauthors = Ellis H | title = Acute appendicitis | journal = British Journal of Hospital Medicine | volume = 73 | issue = 3 | pages = C46–48 | date = March 2012 | pmid = 22411604 | doi = 10.12968/hmed.2012.73.sup3.C46 }}</ref> In 2013, it resulted in 72,000 deaths globally, down from 88,000 in 1990.<ref name=GBD2014>{{cite journal | title = Global, regional, and national age-sex specific all-cause and cause-specific mortality for 240 causes of death, 1990–2013: a systematic analysis for the Global Burden of Disease Study 2013 | journal = Lancet | volume = 385 | issue = 9963 | pages = 117–171 | date = January 2015 | pmid = 25530442 | pmc = 4340604 | doi = 10.1016/S0140-6736(14)61682-2 | vauthors= ((GBD 2013 Mortality Causes of Death Collaborators)) }}</ref>

In the United States, there were nearly 293,000 hospitalizations involving appendicitis in 2010.<ref name=Barrett2013/> Appendicitis is one of the most frequent diagnoses for emergency department visits resulting in hospitalization among children ages 5–17 years in the United States.<ref>{{cite report |last1=Wier |first1=Lauren M. |first2=Hao |last2=Yu |last3=Owens |first3=Pamela L. |last4=Washington |first4=Raynard |url=https://hcup-us.ahrq.gov/reports/statbriefs/sb157.jsp |title=Overview of Children in the Emergency Department, 2010 |work=Healthcare Cost and Utilization Project Statistical Brief #157 |publisher=[[Agency for Healthcare Research and Quality]] |date=June 2013 |url-status=live |archive-url=https://web.archive.org/web/20131203025643/http://hcup-us.ahrq.gov/reports/statbriefs/sb157.jsp |archive-date=2013-12-03 }}</ref>

Adults presenting to the emergency department with a known family history of appendicitis are more likely to have this disease than those without.<ref>{{Cite journal |last1=Drescher |first1=Michael |last2=Marcotte |first2=Shannon |last3=Grant |first3=Robert |last4=Staff |first4=Ilene |date=2012-12-01 |title=Family History is a Predictor for Appendicitis in Adults in the Emergency Department |url=http://www.escholarship.org/uc/item/9zf1h82p |journal=Western Journal of Emergency Medicine |volume=13 |issue=6 |pages=468–471 |doi=10.5811/westjem.2011.6.6679|pmid=23359540 |pmc=3555584 }}</ref>

== See also ==
* [[:Category:Deaths from appendicitis|Deaths from appendicitis]]
* [[Evan O'Neill Kane]]
* [[Leonid Rogozov]]
{{Clear}}

== References ==
{{Reflist}}

== External links ==
{{Commons category|Appendicitis}}
* [http://www.claripacs.com/case/CL0012 CT of the abdomen showing acute appendicitis]
* [https://web.archive.org/web/20070223052616/http://www.surgeons.org.uk/general-surgery-tutorials/appendicitis.html Appendicitis, history, diagnosis and treatment] by Surgeons Net Education
* [http://www.merck.com/mmpe/sec02/ch011/ch011e.html Appendicitis: Acute Abdomen and Surgical Gastroenterology] from the Merck Manual Professional (content last modified September 2007)
* [https://www.healthnsurgery.com/appendicitis-symptoms-causes-and-treatment/ Appendicitis – Symptoms Causes and Treatment] {{Webarchive|url=https://web.archive.org/web/20210227115251/https://www.healthnsurgery.com/appendicitis-symptoms-causes-and-treatment/ |date=2021-02-27 }} at Health N Surgery

{{Medical condition classification and resources
| ICD10          = {{ICD10|K|35||k|35}} - {{ICD10|K|37||k|35}}
| ICD9           = {{ICD9|540}}-{{ICD9|543}}
| MedlinePlus    = 000256
| DiseasesDB     = 885
| eMedicineSubj  = med
| eMedicineTopic = 3430
| eMedicine_mult = {{eMedicine2|emerg|41}} {{eMedicine2|ped|127}} {{eMedicine2|ped|2925}}
| MeshName       = Appendicitis
| MeshNumber     = C06.405.205.099
}}
{{Digestive system diseases}}
{{Authority control}}

[[Category:Acute pain]]
[[Category:Diseases of appendix]]
[[Category:General surgery]]
[[Category:Inflammations]]
[[Category:Medical emergencies]]
[[Category:Wikipedia emergency medicine articles ready to translate]]
[[Category:Wikipedia medicine articles ready to translate]]