Researchers from Belgium and the Netherlands may have found the cause of Nodding syndrome. The study was published in the journal Science Translational Medicine suggests the neurological disease is caused by an autoimmune response to parasitic proteins. In 2012, there were 3,000 reported cases of nodding syndrome, according to the National Institutes of Health (NIH).
Nodding Syndrome is a form of pediatric epilepsy found in some areas of East Africa including Sudan, Tanzania, and northern Uganda. Emerging in the 1960s, nodding syndrome affects the mental and physical states of children between the ages of five and 15. The symptoms of the disease include a permanent stunting of growth, severe cognitive deterioration, and pathological nodding seizure sometimes beginning when the child feels cold. Severe seizures can cause children to collapse, further injuring themselves. Currently, there is no known cure for the disease and treatment is currently only for the symptoms and not the cause.
Avindra Nath, MD and clinical director of the NIH’s National Institute of Neurological Disorders and Stroke said that epilepsy and other forms of neurological disorders may actually be autoimmune diseases. Those who have the disease can lead to malnutrition while others die from “seizure-associated traumas such as fatal burns and drowning.”
Previous studies have linked Nodding Syndrome and the parasitic worm Onchocerca volvulus. The worm can also cause river blindness and is spread by black flies in places where there are many afflicted with the syndrome. It is unclear if the parasite caused the neurological disorder.
The study involved collecting and comparing “serum samples” from patients with the disease and healthy people who all live in the same Ugandan village. The results showed that samples collected from patients had high levels of antibodies. Antibodies were also found in the cerebrospinal fluid of Nodding syndrome patients. In previous studies, it was found in muscles, but this was the first time the antibody was found in the nervous system. Nath’s research team then examined brain tissue and also found the antibody there as well. It was found in the regions associated with Nodding Syndrome symptoms.
The results, according to the research team may help develop a test to identify those who could develop the disease. All of this suggests that the Nodding Syndrome may be an autoimmune disease, where the immune system attacks the body’s proteins instead of foreign substances. Targeting the immune system may be an “effective treatment against this disorder and possibly other forms of epilepsy,” Nath said. Dr. Nath and his team is doing further research and developing a model to study the disease and potential therapies.
By Cheryl Werber
Photo Courtesy Avindra Nath, M.D., NINDS.