Sept. 30, 1999 (Minneapolis) -- Researchers at the National Institute of Mental Health (NIMH) have found that some children whose symptoms of obsessive-compulsive disorder (OCD) and tic disorders were worsened by a common strep infection can be successfully treated with one of two procedures used for disorders of the immune system. The findings appear in the Oct. 2 issue of The Lancet.
OCD and tic disorders affect 1-2% of school-aged children and adolescents. Researchers know from previous studies that in a small number of children suffering from the obsessional thoughts and compulsive behaviors typical of these disorders, symptoms suddenly get worse following a strep infection such as strep throat or a skin infection due to this bacteria.
The two procedures -- called plasma exchange and intravenous immunoglobulin -- were both found by the researchers to lead to a significant improvement in these children. Plasma exchange involves removing some blood from the body and then transferring the blood back to the body after removal of substances that activate the immune system. Intravenous immunoglobulin is given through a vein and is a medication consisting of antibodies to help boost the body's immune system.
The thought behind the procedures, which are used for multiple medical conditions, is removing from the body what is causing the exaggerated response to the strep infection, and then giving back to the body what it needs to fight the infection appropriately.
"A few children [in the study group] were able to discontinue all psychotropic (behavior altering) medications after treatments," lead researcher Susan Swedo, MD, tells WebMD. Swedo, who is chief of pediatrics and developmental neuropsychiatry at the NIMH in Bethesda, Md., emphasizes that while all patients in the study already had OCD, tic disorders, or Tourette syndrome, most children with strep infections are not at risk for developing these disorders. "In fact, strep infections are very common, and strep-triggered neuropsychiatric disorders are quite rare," she says.
The researchers studied 30 children, aged 9-15, with severe, infection-induced worsening of OCD or tic disorders, including Tourette syndrome, in their study. Following complete medical evaluation, the children were randomly assigned to receive one of three treatments: plasma exchange, intravenous immunoglobulin, or placebo (saline solution). The active drugs were chosen because of their safety and effectiveness in a variety of childhood and adult diseases related to the immune system, according to the researchers.
Ratings performed one month after treatment showed that patients in both the plasma exchange and intravenous immunoglobulin groups were much improved. And treatment gains remained one year afterwards, with 14 of 17 subjects "much" or "very much improved." In contrast, symptoms changed little in the children who received placebo.
On average, children now had good functioning in all social areas, according to Swedo and colleagues. In addition, the parents often reported that "my child's back to his old self again," and children reported that "things are a lot easier now," write the authors.
"The study also appeared to demonstrate that one of the treatments, plasma exchange, was more effective than intravenous immunoglobulin in reducing the severity of tic symptoms, and may be more effective in also reducing OCD symptoms and functional impairment. Both treatments appeared to be generally well-tolerated by youngsters, which is important in determining the overall acceptability of this form of treatment to patients and their families," John Piacentini, PhD, says in an interview with WebMD. Piacentini is associate professor-in-residence at UCLA School of Medicine and the director of the Childhood OCD and Anxiety Program, which is also in Los Angeles.
"Patients and parents should have renewed hope that we will eventually discover the cause of their symptoms, and a curative treatment," Swedo says. "In the meantime, they should know that over 80% of patients with OCD and tics can be helped by medication and/or behavior therapy, so it's worth seeking treatment."
Harvey Singer, MD, director of pediatric neurology at Johns Hopkins University School of Medicine in Baltimore, presents his views about the study in an accompanying commentary. "Although potentially promising for the highly selected patient," these two therapies are not ready for routine use, he writes.