Increased prevalence of autoimmune disorders and autoantibodies in parents of children with opsoclonus-myoclonus syndrome (OMS).

Opsoclonus-myoclonus syndrome (OMS) is a rare neurological disease in childhood which can be associated with neuroblastoma. Since autoantibodies have been detected in some patients with OMS, an autoimmune etiology is suspected. We compared the prevalence of autoimmune disorders and autoantibodies in parents of children with OMS and in a group of controls of same age and sex. Autoimmune diseases were found in 15.8% of the parents of OMS children, but only in 2.0% of the controls (p<0.001) There was also an increased prevalence of autoantibodies in the OMS parents (42.8% vs. 8.0%, p<0.001). Thyroid diseases were the most frequent autoimmune diseases found, followed by inflammatory rheumatic diseases. Interestingly, the OMS parents also had significantly more autoantibodies against CNS structures than the controls (p<0.01). These findings support the autoimmune hypothesis of childhood OMS and may also hint to a genetic susceptibility for OMS.