Ask the doctors: PANDAS symptoms mimic those of OCD
Dear Doctors: Our 8-year-old son got sick with strep throat and had to miss a family camping trip. When my sister called to check on him, she asked me if I knew strep throat can cause obsessive-compulsive disorder. Is that really true? The strep was cured with antibiotics, and our son seems fine.
Dear Reader: Your sister is referring to a condition known as pediatric autoimmune neuropsychiatric disorders associated with streptococcal infections. It is commonly shortened to the acronym PANDAS. Although there is overlap with the symptoms of OCD, it is not the same thing. Unlike OCD, which is believed to arise from a combination of genetics, brain structure and environmental factors, PANDAS is associated with group A streptococcal bacterial infection. These are microbes that cause strep throat, scarlet fever and impetigo.
The disorder, first identified in 1998, occurs most often between age 3 and the onset of puberty. While possible in adolescents and adults, the data so far suggest this is rare. The symptoms of PANDAS are similar to OCD. OCD is a disruptive and often debilitating mental health disorder marked by repeated cycles of obsessive and ritualistic tics, behaviors, actions and thoughts. OCD typically presents gradually.
The onset of PANDAS, by contrast, is quite sudden. Parents report seeing their child change overnight. In addition to tics and compulsions, symptoms of PANDAS can include an inability to regulate emotions; changes to sleep patterns; weight loss due to food phobias and restrictions; changes to physical coordination, attention span and concentration; and anxiety, fear and depression.
Although PANDAS is linked to an infection with group A strep bacteria, the bacteria itself is not the cause – it is the immune system’s response to the infection. Group A strep is adept at a stealth attack known as molecular mimicry. This is when a pathogen uses biological markers to disguise itself as the tissues it is invading. When the immune system finally identifies the pathogen, it targets not only the invader, but also the cells in the body that it was imitating. With PANDAS, this is believed to take place in the brain, giving rise to the neurological and psychiatric symptoms. Recent research also suggests a genetic link to an increased risk of the syndrome.
Strep bacteria are estimated to cause up to 35% of sore throats in children. In addition to an inflamed and painful throat, symptoms can include headache, fever, chills and loss of appetite. People also often develop white spots or patches on the back of the throat. Strep infection is easily diagnosed with a throat culture, and thanks to antibiotics like amoxicillin or penicillin, can be successfully treated. Early treatment has been shown to reduce the risk of the immune response linked to PANDAS. Children who develop PANDAS often respond well to antibiotics and symptoms gradually resolve. If your medical care provider is unfamiliar with PANDAS, information is available at the International OCD Foundation and the PANDAS Physicians Network.
Send your questions to askthedoctors@mednet.ucla.edu.