Editing Splenectomy

{{Short description|Surgical removal of the spleen}}
{{More citations needed|date=August 2016}}
{{Infobox medical intervention |
  Name        = Splenectomy |
  Image       = Spleen after spleenectomy.jpg |
  Caption     = Surgically removed spleen of a child with [[thalassemia]]. It is about 15 times larger than normal. |
  ICD10       = |
  ICD9        = {{ICD9proc|41.43}}, {{ICD9proc|41.5}} |
  MeshID      = D013156 |
  OPS301      = {{OPS301|5-413}} |
  OtherCodes  = |
}}
A '''splenectomy''' is the [[Surgery|surgical procedure]] that partially or completely removes the [[spleen]]. The spleen is an important organ in regard to [[Immune system|immunological function]] due to its ability to efficiently destroy [[Bacterial capsule|encapsulated bacteria]]. Therefore, removal of the spleen runs the risk of [[overwhelming post-splenectomy infection]], a [[medical emergency]] and rapidly fatal disease caused by the inability of the body's immune system to properly fight [[infection]] following splenectomy or [[asplenia]].<ref>{{Cite journal|last1=Taniguchi|first1=Leandro Utino|last2=Correia|first2=Mário Diego Teles|last3=Zampieri|first3=Fernando Godinho|date=December 2014|title=Overwhelming post-splenectomy infection: narrative review of the literature|url=https://pubmed.ncbi.nlm.nih.gov/25318011/|journal=Surgical Infections|volume=15|issue=6|pages=686–693|doi=10.1089/sur.2013.051|issn=1557-8674|pmid=25318011}}</ref>

Common indications for splenectomy include [[Splenic injury|trauma]], [[Splenic tumor|tumors]], [[splenomegaly]] or for [[Hematologic disease|hematological disease]] such as [[Sickle cell disease|sickle cell anemia]] or [[thalassemia]].<ref>{{Cite journal|last=Weledji|first=Elroy P.|date=2014|title=Benefits and risks of splenectomy|journal=International Journal of Surgery (London, England)|volume=12|issue=2|pages=113–119|doi=10.1016/j.ijsu.2013.11.017|issn=1743-9159|pmid=24316283|doi-access=free}}</ref>

==Indications==
[[File:Infiltrative (poorly cohesive) gastric cancer.jpg|thumb|A [[gross anatomy]] specimen of a total [[gastrectomy]], splenectomy for infiltrative [[gastric cancer]]]]
The spleen is an organ located in the [[abdomen]] next to the [[stomach]]. It is composed of [[red pulp]] which filters the blood, removing foreign material, damaged and worn out [[red blood cell]]s. It also functions as a storage site for [[Human iron metabolism|iron]], [[red blood cell]]s and [[platelet]]s. The rest (~25%) of the spleen is known as the [[white pulp]] and functions like a large [[lymph node]] being the largest [[Secondary Lymphoid Organ|secondary lymphoid organ]] in the body.<ref>{{Cite journal|last=Cesta|first=Mark F.|date=2006|title=Normal structure, function, and histology of the spleen|url=https://pubmed.ncbi.nlm.nih.gov/17067939/|journal=Toxicologic Pathology|volume=34|issue=5|pages=455–465|doi=10.1080/01926230600867743|issn=0192-6233|pmid=17067939|s2cid=39791978}}</ref> Apart from regular lymphatic function the white pulp contains splenic [[macrophage]]s which are particularly good at destroying ([[phagocytosis]]) [[Bacterial capsule|encapsulated bacteria]] such as ''[[Streptococcus pneumoniae]].''<ref name=":0">{{Cite journal|last1=Di Sabatino|first1=Antonio|last2=Carsetti|first2=Rita|last3=Corazza|first3=Gino Roberto|date=2011-07-02|title=Post-splenectomy and hyposplenic states|url=https://pubmed.ncbi.nlm.nih.gov/21474172/|journal=Lancet|volume=378|issue=9785|pages=86–97|doi=10.1016/S0140-6736(10)61493-6|issn=1474-547X|pmid=21474172|s2cid=30554953}}</ref> The spleen is also known to function as a site for the development of new red blood cells from their hematopoietic stem cell precursors, and particularly in situations in which the [[bone marrow]], the normal site for this process, has been compromised by a disorder such as [[leukemia]]. The spleen is enlarged in a variety of conditions such as [[malaria]], [[Infectious mononucleosis|mononucleosis]] and most commonly in cancers of the [[Lymphatic system|lymphatic]]s, such as [[lymphoma]]s or [[leukemia]].

It is removed under the following circumstances:
# When it becomes [[Splenomegaly|very large]] such that it becomes destructive to [[platelet]]s/red blood cells or rupture is imminent
# For diagnosing certain [[lymphoma]]s
# Certain cases of splenic abscess
# Certain cases of [[wandering spleen]]
# Splenic vein thrombosis with bleeding [[Gastric varices]]
# When platelets are destroyed in the spleen as a result of an [[auto-immune]] condition, such as [[idiopathic thrombocytopenic purpura]].
# When the spleen bleeds following [[physical trauma]]
# Following spontaneous [[Ruptured spleen|rupture]]
# For long-term treatment of congenital erythropoietic [[porphyria]] (CEP) if severe [[hemolytic anemia]] develops<!--
  --><ref name="eMedicine2006-Frye">{{cite web | author=Frye R.|  title=Porphyria, Cutaneous | url=http://www.emedicine.com/ped/topic1871.htm | publisher=eMedicine | date=2006-03-02 | access-date= 2006-03-28}}</ref>
# The spread of gastric cancer to splenic tissue
# When using the [[splenic artery]] for kidney revascularisation in [[renovascular hypertension]].
# For long-term treatment of congenital pyruvate kinase (PK) deficiency
# Those who have a severe version of the hereditary blood disorder Spherocytosis.
# During [https://www.cancer.org/cancer/pancreatic-cancer/treating/surgery.html surgical resection of a pancreatic cancer]

The classical cause of traumatic damage to the spleen is a blow to the abdomen during a sporting event. In cases where the spleen is enlarged due to illness (mononucleosis), trivial activities, such as leaning over a counter or straining while defecating, can cause a rupture.

==Procedure==
[[Laparoscopy]] is the preferred procedure in cases where the spleen is not too large and when the procedure is elective. [[Open surgery]] is performed in [[Splenic injury|trauma]] cases or if the [[Splenomegaly|spleen is enlarged]].  Either method is major surgery and is performed under [[general anesthesia]]. Vaccination for [[Streptococcus pneumoniae|''S. pneumoniae'']], ''[[Haemophilus influenzae|H. influenza]]'' and [[Neisseria meningitidis|''N. meningitidis'']] should be given pre-operatively if possible to minimize the chance of [[overwhelming post-splenectomy infection]] (OPSI), a rapid-developing and highly fatal type of [[septicaemia]]. The spleen is located and disconnected from its [[Splenic artery|arteries]]. The ligaments holding the spleen in place, [[gastrosplenic ligament]], [[splenorenal ligament]] and [[splenocolic ligament]], are dissected and the organ is removed.  In some cases, one or more [[accessory spleen]]s are discovered and also removed during surgery. The incisions are closed and when indicated, a drain is left. If necessary, tissue samples are sent to a laboratory for analysis.{{citation needed|date=January 2022}}

==Side effects==
Splenectomy causes an increased risk of [[sepsis]], particularly [[Overwhelming post-splenectomy infection|overwhelming post-splenectomy sepsis]] due to encapsulated organisms such as ''[[S. pneumoniae]]'' and ''[[Haemophilus influenzae]]'' which are no longer able to be destroyed.<ref name=":0" /> It has been found that the risk of acquiring sepsis is 10 to 20 times higher in a splenectomized patient compared to a non-splenectomized patient, which can result in death, especially in young children.<ref name="pmid23801854">{{cite journal | vauthors = Tarantino G, Scalera A, Finelli C | title = Liver-spleen axis: intersection between immunity, infections and metabolism | journal = World Journal of Gastroenterology | volume = 19 | issue = 23 | pages = 3534–42 | date = June 2013 | pmid = 23801854 | pmc = 3691032 | doi = 10.3748/wjg.v19.i23.3534 | doi-access = free }}</ref> Therefore, patients are administered the [[pneumococcal conjugate vaccine|pneumococcal conjugate vaccine (Prevnar)]], [[Hib vaccine]], and the [[meningococcal vaccine]] post-operatively (see [[asplenia]]).  These bacteria often cause a sore throat under normal circumstances but after splenectomy, when infecting bacteria cannot be adequately [[opsonize]]d, the infection becomes more severe.{{citation needed|date=January 2022}}

Splenectomy also increases the severity of [[babesiosis]], Splenectomized patients are more susceptible to contracting babesiosis and can die within five to eight days of symptom onset.<ref name=niaid1>{{cite web|url=http://www3.niaid.nih.gov/topics/babesiosis/|title=Babesiosis |archive-url=https://web.archive.org/web/20090305010538/http://www3.niaid.nih.gov/topics/babesiosis/ |archive-date=2009-03-05 |date=2009-02-19 |publisher=National Institute of Allergy and Infectious Diseases, National Institutes of Health}}</ref> They have severe hemolytic anemia, and occasional [[hepatomegaly]] has been documented. [[Parasitemia]] levels can reach up to 85% in patients without spleens, compared to 1–10% in individuals with spleens and effective immune systems.<ref name=Harrisons>{{cite book|last1=Gelfand|first1=Jeffrey A.|last2=Vannier|first2=Edouard|title=Harrison's Principles of Internal Medicine, 17e|chapter=Ch. 204: Babesiosis|date=6 March 2008|publisher=McGraw-Hill's Access Medicine|chapter-url=http://www.accessmedicine.com/content.aspx?aID=2892931|isbn=978-0071466332}}</ref>

An increase in blood [[leukocytes]] can occur following a splenectomy.<ref name="BMJ1996">{{cite journal | author =  Working Party of the British Committee for Standards in Haematology Clinical Haematology Task Force | title = Guidelines for the prevention and treatment of infection in patients with an absent or dysfunctional spleen | journal = BMJ | volume = 312 | issue = 7028 | pages = 430–4 | date = February 1996 | pmid = 8601117 | pmc = 2350106 | doi = 10.1136/bmj.312.7028.430 | url = http://bmj.bmjjournals.com/cgi/content/full/312/7028/430 }}</ref>  The post-splenectomy [[platelet]] count may rise to abnormally high levels ([[thrombocytosis]]), leading to an increased risk of potentially fatal [[clot]] formation. Mild thrombocytosis may be observed after a splenectomy due to the lack of sequestering and destruction of platelets that would normally be carried out by the spleen. In addition, the splenectomy may result in a slight increase in the production of platelets within the bone marrow. Normally, erythrocytes are stored and removed from the circulating blood by the spleen, including the removal of damaged erythrocytes. However, after a splenectomy the lack of presence of the spleen means this function cannot be carried out so damaged erythrocytes will continue to circulate in the blood and can release substances into the blood. If these damaged erythrocytes have a procoagulant activity then the substances they release can lead to the development of a procoagulant state and this can cause thromboembolic events e.g. pulmonary embolism, portal vein thrombosis and deep vein thrombosis.<ref name="pmid23801854"/> There also is some conjecture that post-splenectomy patients may be at elevated risk of subsequently developing [[diabetes]].<ref>{{Cite news | first = Gina | last = Kolata | name-list-style = vanc | title = A Diabetes Researcher Forges Her Own Path to a Cure | url = https://www.nytimes.com/2004/11/09/health/a-diabetes-researcher-forges-her-own-path-to-a-cure.html | newspaper = The New York Times | date = 9 November 2004 }}</ref>  Splenectomy may also lead to chronic [[neutrophilia]].  Splenectomy patients typically have [[Howell-Jolly bodies]]<ref>{{WhoNamedIt|synd|1596}}</ref><ref>{{cite journal | vauthors = Katcher AL | date = Mar 1980 | title = Familial asplenia, other malformations, and sudden death | journal = Pediatrics | volume = 65 | issue = 3| pages = 633–5 | doi = 10.1542/peds.65.3.633 | pmid = 7360556 | s2cid = 25109676 }}</ref> and less commonly [[Heinz bodies]] in their blood smears.<ref>{{cite book | title = Hematology: Clinical Principles and Applications | vauthors = Rodak B, Fritsma G, Doig K }}</ref> [[Heinz bodies]] are usually found in cases of G6PD ([[Glucose-6-Phosphate Dehydrogenase]]) and [[chronic liver disease]].<ref name="Irwin_2001">{{cite journal | vauthors = Irwin JJ, Kirchner JT | title = Anemia in children | journal = American Family Physician | volume = 64 | issue = 8 | pages = 1379–86 | date = October 2001 | pmid = 11681780 }}</ref>

A splenectomy also results in a greatly diminished frequency of memory B cells.<ref>{{cite journal | vauthors = Kruetzmann S, Rosado MM, Weber H, Germing U, Tournilhac O, Peter HH, Berner R, Peters A, Boehm T, Plebani A, Quinti I, Carsetti R | title = Human immunoglobulin M memory B cells controlling Streptococcus pneumoniae infections are generated in the spleen | journal = The Journal of Experimental Medicine | volume = 197 | issue = 7 | pages = 939–45 | date = April 2003 | pmid = 12682112 | pmc = 2193885 | doi = 10.1084/jem.20022020 }}</ref> A 28-year follow-up of 740 [[World War II]] veterans who had their spleens removed on the battlefield showed a significant increase in the usual death from [[pneumonia]] (6 deaths rather than the expected 1.74) and an increase in the deaths from [[ischemic heart disease]] (41 deaths rather than the expected 30.26) but not from other conditions.<ref>{{cite journal | vauthors = Robinette CD, Fraumeni JF | title = Splenectomy and subsequent mortality in veterans of the 1939-45 war | journal = Lancet | volume = 2 | issue = 8029 | pages = 127–9 | date = July 1977 | pmid = 69206 | doi = 10.1016/S0140-6736(77)90132-5 | s2cid = 38605411 }}</ref>

==Subtotal splenectomy==
Much of the spleen's protective roles can be maintained if a small amount of spleen can be left behind.<ref name="pmid957066">{{cite journal | vauthors = Grosfeld JL, Ranochak JE | title = Are hemisplenectomy and/or primary splenic repair feasible? | journal = Journal of Pediatric Surgery | volume = 11 | issue = 3 | pages = 419–24 | date = June 1976 | pmid = 957066 | doi = 10.1016/S0022-3468(76)80198-4 }}</ref> Where clinically appropriate, attempts are now often made to perform either surgical subtotal (partial) splenectomy,<ref name="pmid11154215">{{cite journal | vauthors = Bader-Meunier B, Gauthier F, Archambaud F, Cynober T, Miélot F, Dommergues JP, Warszawski J, Mohandas N, Tchernia G | title = Long-term evaluation of the beneficial effect of subtotal splenectomy for management of hereditary spherocytosis | journal = Blood | volume = 97 | issue = 2 | pages = 399–403 | date = January 2001 | pmid = 11154215 | doi = 10.1182/blood.V97.2.399 | s2cid = 22741973 | doi-access =  }}</ref> or partial splenic [[embolization]].<ref name="pmid18028435">{{cite journal | vauthors = Pratl B, Benesch M, Lackner H, Portugaller HR, Pusswald B, Sovinz P, Schwinger W, Moser A, Urban C | title = Partial splenic embolization in children with hereditary spherocytosis | journal = European Journal of Haematology | volume = 80 | issue = 1 | pages = 76–80 | date = January 2008 | pmid = 18028435 | doi = 10.1111/j.1600-0609.2007.00979.x | s2cid = 41343243 }}</ref>
In particular, whilst vaccination and antibiotics provide good protection against the risks of asplenia, this is not always available in poorer countries.<ref name="pmid18031639">{{cite journal | vauthors = Sheikha AK, Salih ZT, Kasnazan KH, Khoshnaw MK, Al-Maliki T, Al-Azraqi TA, Zafer MH | title = Prevention of overwhelming postsplenectomy infection in thalassemia patients by partial rather than total splenectomy | journal = Canadian Journal of Surgery | volume = 50 | issue = 5 | pages = 382–6 | date = October 2007 | pmid = 18031639 | pmc = 2386178 }}</ref> However, as it may take some time for the preserved splenic tissue to provide the full protection, it has been advised that preoperative vaccination still be given.<ref name="pmid9660206">{{cite journal | vauthors = Kimber C, Spitz L, Drake D, Kiely E, Westaby S, Cozzi F, Pierro A | title = Elective partial splenectomy in childhood | journal = Journal of Pediatric Surgery | volume = 33 | issue = 6 | pages = 826–9 | date = June 1998 | pmid = 9660206 | doi = 10.1016/S0022-3468(98)90651-0 }}</ref>

== See also ==
* [[Asplenia]]
* [[Autosplenectomy]]
* [[Overwhelming post-splenectomy infection]] (OPSI)
* [[Lymphatic system]]
* [[Infectious mononucleosis]]
* [[List of surgeries by type]]

== References ==
{{Reflist}}

{{Operations and other procedures of the hemic and lymphatic system}}
{{Authority control}}

[[Category:Abdominal surgical procedures]]
[[Category:Lymphatic organ surgery]]
[[Category:Spleen (anatomy)]]
[[Category:Surgical removal procedures]]