For about a decade, Susan Swedo, chief of the Pediatric and Developmental Neuropsychiatry Branch of the National Institute of Mental Health (NIMH), has been investigating how an ordinary strep infection can trigger an autoimmune response leading to obsessive-compulsive disorder (OCD). She, her colleagues at NIMH, and other researchers have been exploring this link with a goal of better understanding the role of the brain in mental disorders and developing better OCD treatments.
Though strep is common, this phenomenon--called pediatric autoimmune neuropsychiatric disorders associated with streptococcal infections (PANDAS)--is rare, Swedo points out: "A child in the second, third, and fourth grade will have at least one strep infection each winter and usually two or three. PANDAS, we think, are quite rare. We know that obsessive-compulsive disorder occurs in only about 1 percent of children. We don't have any idea how much is strep-triggered. We're trying to get those numbers."
The common ...
