PANDAS in Identical Twins: Environmental Factors Play Role

Pediatric autoimmune neuropsychiatric disorders associated with Streptococcus (PANDAS) involves childhood-onset obsessive compulsive disorder and tic disorders. The symptoms  resemble Sydenham chorea, primarily because they have an acute onset after a bout with group A Streptococcus and show neurological signs. With PANDAS, obsessive compulsive disorder and tics are key features, but there are others.

In this research, three children with PANDAS were studied along with their genetically identical siblings. Two were cases of twins, and one was of triplets.

The researchers found: “Despite identical genetics, presentations showed marked variation across siblings (from a full PANDAS presentation to asymptomatic).” Abstract

Environmental factors encompass in part, physical conditions in the womb, parental health, foods, allergens, chemical exposures, infections, even emotional situations. What this study tells us is that doctors and families need to be vigilant in looking for environmental issues that could impact a child’s symptoms. Once these issues or triggers are determined, efforts can be made to treat the situation. Without exploring the triggers, proper therapies cannot be determined.