Clinical clues for autoimmunity and neuroinflammation in patients with autistic regression

Abstract

Aim: Autistic regression is a unique variant within the autism spectrum disorders (ASDs), with recent reports raising the possibility of immune aetiology. This study explores clinical clues for an association between autistic regression and autoimmunity. Method: Single-centre charts of children diagnosed with ASD in 2014 were reviewed. We compared the rates of: (1) familial autoimmunity in first-degree and second-degree relatives; (2) febrile illness preceding initial parental concern, as a potential precipitant of immune activation; and (3) possible non-immune precipitants such as pregnancy and postnatal complications. Results: The charts of 206 children with ASD and 33 diagnosed with autistic regression variant were reviewed. The incidence of febrile illness in the 6 months prior to initial parental concern was significantly higher in the children with autistic regression compared with those with ASD (30% vs 0%; p<0.001). The overall prevalence of familial autoimmunity was also higher in children with autistic regression compared with those with ASD (33% vs 12%; p<0.001). Type 1 diabetes and autoimmune thyroiditis were both more common in families with children with autistic regression. Other non-immune risk factors did not differ between the two groups. Interpretation: Our findings suggest that predisposition to autoimmunity, and immune/inflammatory activation, may be associated with autistic regression.