Editing Sydenham's chorea (section)

==Signs and symptoms==
Sydenham's chorea is characterized by the abrupt onset (sometimes within a few hours) of [[neurological symptoms]], classically [[chorea]], which are non-rhythmic, writhing or explosive involuntary movements.  Usually all four limbs are affected, but there are cases reported where just one side of the body is affected (''hemichorea''). Typical chorea includes repeated wrist [[hyperextension]], grimacing, and lip pouting. The fingers can move as if playing the piano. There may be tongue [[fasciculations]] ("bag of worms") and ''motor impersistence'', for example, the "milkmaid sign" (grip strength fluctuates, as if [[hand milking]] a cow), or inability to sustain tongue protrusion (called [[jack-in-the-box]] tongue<ref>{{Cite book |last1=Verma |first1=Anoop |url=https://books.google.com/books?id=U3KSDwAAQBAJ&dq=Sydenham's+chorea+%22snake%22+tongue&pg=PA354 |title=IAP Textbook of Pediatric Neurology |last2=Kunju |first2=P. A. M. |date=2019-05-31 |publisher=Jaypee Brothers Medical Publishers |isbn=978-93-5270-979-3 |pages=354 |language=en}}</ref> or [[Snake#Locomotion|serpentine]] tongue,<ref>{{Cite book |last1=Talley |first1=Nicholas J. |url=https://books.google.com/books?id=j_r_DwAAQBAJ&dq=Sydenham's+chorea+eyes&pg=PA577 |title=Talley and O'Connor's Examination Medicine - epub: A Guide to Physician Training |last2=O’Connor |first2=Simon |date=2020-10-30 |publisher=Elsevier Health Sciences |isbn=978-0-7295-8875-1 |pages=577 |language=en}}</ref> as the tongue slides in and out of the mouth), or eye closure.

There is usually a loss of [[fine motor control]], which is particularly obvious in [[handwriting]] if the child is of school age.  Speech is often affected ([[dysarthria]]), as is walking; legs will suddenly give way or flick out to one side, giving an irregular [[gait]] and the appearance of skipping or dancing. Underlying the abnormal movements is often low tone ([[hypotonia]]) which may not become obvious until treatment is started to suppress the chorea.  

The severity of the condition can vary from just some instability on walking and difficulty with handwriting, to the extreme of being wholly unable to walk, talk, or eat (''chorea paralytica'').

Movements cease during sleep.

It is a neuropsychiatric disorder, so besides the motor problems there is classically emotional lability (mood swings, or inappropriate mood), but also tics, anxiety, attention deficit etc.  These can precede the motor symptoms.<ref>{{cite journal|last1=Oosterveer|first1=Daniëlla M.|last2=Overweg-Plandsoen|first2=Wilhelmina C.T.|last3=Roos|first3=Raymund A.C.|date=July 2010|title=Sydenham's Chorea: A Practical Overview of the Current Literature|url=https://www.pedneur.com/article/S0887-8994(10)00035-4/fulltext|journal=Pediatric Neurology|volume=43|issue=1|pages=1–6|doi=10.1016/j.pediatrneurol.2009.11.015|pmid=20682195|access-date=2 March 2021|url-access=subscription}}</ref>

Non-neurologic manifestations of acute rheumatic fever may be present, namely [[carditis]] (up to 70% of cases, often subclinical, so echocardiography required), [[arthritis]], [[erythema marginatum]], and subcutaneous [[Nodule (medicine)|nodules]].

[[File:Erythema marginatum.jpg|thumb|right|alt=Classic rash of rheumatic fever|Erythema marginatum]]

Differentiating these signs from other involuntary movements such as [[tics]] and [[stereotypies]] can be difficult, and since these things are not uncommon they can potentially co-exist.  Diagnosis is often delayed and attributed to another condition such as [[tic disorder]] or [[conversion disorder]].  The controversial [[PANDAS]] (pediatric autoimmune neuropsychiatric disorders associated with streptococcal infections) hypothesis has overlapping clinical features, but Sydenham's chorea is one of the exclusion criteria.  PANDAS can present with chorea but more typically there are [[tics]] or [[stereotypies]] with a psychological component (e.g., [[Obsessive–compulsive disorder|OCD]]).<ref name= Wilbur2019>{{cite journal |vauthors=Wilbur C, Bitnun A, Kronenberg S, Laxer RM, Levy DM, Logan WJ, Shouldice M, Yeh EA |title=PANDAS/PANS in childhood: Controversies and evidence |journal=Paediatr Child Health |volume=24 |issue=2 |pages=85–91 |date=May 2019 |pmid=30996598 |pmc=6462125 |doi=10.1093/pch/pxy145}}</ref><ref name=Sigra2018>{{cite journal |vauthors=Sigra S, Hesselmark E, Bejerot S |title=Treatment of PANDAS and PANS: a systematic review |journal=Neurosci Biobehav Rev |volume=86 |issue= |pages=51–65 |date=March 2018 |pmid=29309797 |doi=10.1016/j.neubiorev.2018.01.001 |s2cid=40827012 |doi-access=free }}</ref><ref>{{cite journal |vauthors=Swedo SE, Leonard HL, Garvey M, etal |title=Pediatric autoimmune neuropsychiatric disorders associated with streptococcal infections: clinical description of the first 50 cases |journal=The American Journal of Psychiatry |volume=155 |issue=2 |pages=264–71 |date=February 1998 |pmid=9464208 |doi= 10.1176/ajp.155.2.264 |s2cid=22081877 |url=http://ajp.psychiatryonline.org/cgi/pmidlookup?view=long&pmid=9464208|url-access=subscription }}</ref>