A study conducted by researchers at the Group Health Center for Health Studies in Seattle has found evidence that links common “strep” infections and the incidence of certain neurological disorders like Tourette’s syndrome, tic disorders, and obsessive compulsive disorder (OCD).
Healthy children between the ages of 4 and 13 were compared with 200 children of the same ages with neurological disorders between 1992 and 1999. The results are published in the journal Pediatrics.
The team found that children with such neurological disorders were twice as likely to have had recent streptococcal infections as healthy children. The body’s natural responses to these infections may be the key since particular antibodies are produced and directed to parts of the brain.
Tourette’s affects about 1% of all children to some degree and is characterized by tics, involuntary vocalization, and, in some cases, the compulsive utterance of obscenities. OCD affects about 1 to 2 % of school-age children and transient tics of one type or another affect as many as 25% of children of primary school age.
It is unclear; however, why most children who contract bacterial throat infections do not go on to develop these disorders.
Children with the disorders described above were found to have been more than twice as likely to have had at least one streptococcal infection within three months before the emergence of neurological symptoms. This figure jumped to more than three times for children who had had two or more such infections within one year of the onset of their diseases.
The researchers pointed out that while there were likely to be a number of different causes for these conditions, the evidence pointed to the infections as one of the triggers. It is also unclear whether treatment with common antibiotics helps prevent the disorders, reduce their severity, or shorten their duration. Each individual’s genes may also play an important role in the process with the infections acting as a trigger.