Antineuronal antibodies in OCD: Comparisons in children with OCD-only, OCD+chronic tics and OCD+PANDAS

Autoimmunity associated with a streptococcal infection has been proposed as a pathogenic mechanism for obsessive–compulsive disorder (OCD) in children. Antibrain antibody profiles were compared in children with OCD-only (n = 13; 14.1 ± 3.1 years), OCD+PANDAS (n = 20; 11.3 ± 1.5 years), OCD+Chronic Tic Disorder (n = 23; 13.4 ± 3.5 years), and controls (n = 29; 12.4 ± 2.4 years) using ELISA (orbitofrontal (OFC) and dorsolateral prefrontal cortex (DLPFC), caudate (CD), cingulate gyrus (CG)), immunoblotting (four regions plus putative antigens), and immunohistochemistry. ELISA and immunohistochemistry showed no differences among groups. Immunoblot showed that a greater percentage of individuals in the OCD+PANDAS cohort had reactive bands at 27 kDa (CD, CG, DLPFC), 36 kDa (CD), and 100 kDa (CD, OFC) and increased peak height at 67 kDa (all regions). Immunoblotting studies using the putative antigens (pyruvate kinase M1, aldolase C, α- and γ-enolase) did not differ among groups. ASO titers were similar in all groups and did not correlate with immunoassays. It remains controversial whether childhood OCD is associated with autoimmune mechanisms.