Existing studies of immune-related comorbidities in childhood-onset OCD are limited by small sample sizes and restriction to assessment of PANS/PANDAS subtypes. This is the largest study to date describing immune-related comorbidities in a general population with childhood-onset OCD and points to high rates of certain inflammatory and infectious conditions in both affected individuals and their first-degree relatives. Our data are consistent with other recent studies suggesting that the increased prevalence of immune-related comorbidities may not be unique to PANS/PANDAS and provide an impetus for additional carefully designed research studies.
