Anti-basal ganglia antibodies in acute and persistent Sydenham's chorea.
OBJECTIVE
To determine the sensitivity and specificity of methods to detect anti-basal ganglia antibodies (ABGA) in Sydenham's chorea (SC).


BACKGROUND
SC is a delayed manifestation of group Abeta hemolytic streptococcal infection typically associated with rheumatic fever (RHF). SC is characterized by chorea and motor and neuropsychiatric symptoms. Patients with SC produce antibodies that cross-react with streptococcal, caudate, and subthalamic nuclei antigens detected using an immunofluorescent (IF) method with inconsistent reports of positivity.


METHODS
The authors developed ELISA and Western immunoblotting (WB) methods to detect ABGA and compared these assays to IF. They investigated samples from patients with acute SC (n = 20), persistent SC (n = 16), control samples from RHF (n = 16), and healthy pediatric volunteers (n = 11).


RESULTS
ABGA ELISA had a sensitivity of 95% and specificity of 93% in acute SC. Both WB and IF had a sensitivity of 100% and specificity of 93%. In the persistent SC group, ABGA sensitivity dropped to 69% using WB and to 63% using IF. Three common basal ganglia antigens were identified by WB in both acute and persistent SC (40 kDa [n = 15], 45 kDa [n = 15], and 60 kDa [n = 13]). There was no antibody reactivity to cerebellum, cerebral cortex, or myelin antigen preparations in any group.


CONCLUSIONS
These results support the hypothesis that Syndenham's chorea is an autoantibody-mediated disorder. Western immunoblotting and immunofluorescence are the best methods for detecting anti-basal ganglia antibodies, and reactivity to basal ganglia antigens of 40, 45, and 60 kDa were commonly seen in both acute and persistent cases of SC.
Neuroimmunology Unit, Neuroinflammation Department, Institute of Neurology, Queen Square, London, UK. A.Church@ion.ucl.ac.uk
A J
AJ
Church
F
F
Cardoso
R C
RC
Dale
A J
AJ
Lees
E J
EJ
Thompson
G
G
Giovannoni
D000208:Acute Disease; D001323:Autoantibodies / Q000032:analysis* / Q000097:blood; D001479:Basal Ganglia / Q000276:immunology*; D015153:Blotting, Western; D016022:Case-Control Studies; D002819:Chorea / Q000276:immunology* / Q000382:microbiology; D002908:Chronic Disease; D004797:Enzyme-Linked Immunosorbent Assay; D019084:Fluorescent Antibody Technique, Indirect; D006801:Humans; D012680:Sensitivity and Specificity; D013290:Streptococcal Infections / Q000276:immunology; D013297:Streptococcus pyogenes / Q000276:immunology
D001323:Autoantibodies