Attention deficit hyperactivity disorder combined subtype and Anti-Yo antibodies

BACKGROUND: Neuroinflammation seems to be involved in ADHD pathogenesis. Recently, in this regard, some evidence suggests the possibility of an autoimmune mechanism related to anti-Purkinje cell antibodies. The aim of this paper is to confirm this evidence searching for a possible specificity for some subtype of ADHD. METHODS: We studied 112 consecutive drug-naïve Caucasian ADHD outpatients, who were attending their first psychiatric examination (91 males and 21 females; median age =108.14 months; sd=34.58 months). K-SADS interview and ADHD rating scale were used for a DSM 5 diagnosis of ADHD and subtype. WISCIII and a validated list of words were used to assess a possible dyslexia. Antibodies to Yo (Purkinje cell cytoplasmic antibody type 1 [PCA-1]) were detected by indirect immunofluorescence assay. RESULTS: Forty-nine point one percent (55) of ADHD children were positive to Anti-Yo antibodies. A lower percentage than in previous studies. We found that in the Anti-Yo positive children, the subtype most represented was significantly the combined subtype. No significant relation was found with ADHD plus Dyslexia children. CONCLUSIONS: The number of ADHD subjects positive to Anti-Yo antibodies is less than in previous studies, but it remains interesting and it is more likely to find a positive child in the combined ADHD than in the other subtypes.