Parasitic brain disease reported in area hospitals (10-13-99)An intestinal parasite that has long existed in areas of Mexico and nations to the south is making its way across the border with more frequency.
With an infection cycle that includes infiltration of the brain and nervous system, the resulting disease, neurocysticercosis, has caught the attention of researcher Judy Teale, Ph.D., a professor in the Department of Microbiology at the Health Science Center. Dr. Teale is working to determine the effects of current treatments for the disease and the role of certain cells in immune response.
Neurocysticercosis begins with the ingestion of parasitic eggs, eventually resulting in the infection of the brain and central nervous system by larvae. Some patients suffer no outward effects and the disease is not found until the patients have died. Others exhibit a variety of maladies, including headaches, nausea and seizures. Depending upon the length of infection and the location of the parasitic larvae, patients may suffer life-threatening conditions, including increased pressure on the brain.
The parasitic infection generally results from inadequate sanitation, including unsanitary food preparation. The disease usually is seen in Third World countries where standards in food preparation and sanitation are lower, but as people migrate from Mexico into the United States, San Antonio-area hospitals are seeing more cases. University Hospital, adjacent to the Health Science Center, treats several cases a month.
"It is the most common parasitic disease of the central nervous system worldwide," Dr Teale said. "It is a really serious problem."
It is a serious problem that has seen little in the way of research. Current treatments, which include anti-helminthic drugs, have been known to cause adverse side effects and additional problems for patients instead of alleviating illness.
Dr. Teale is working to define the brain's immune response following treatment with the anti-helminthic drugs, including which cells are involved and what those cells secrete. Dr. Teale has determined that one particular type of cell, the gamma delta T-cell, is involved in controlling the infection in animal models. Further research will determine exactly what those cells do.
Prevention is key to stopping the spread of neurocysticercosis, Dr. Teale said. The old adage warning tourists to steer clear of the drinking water in many foreign countries may not be the only caution to remember when traveling. Fruits and vegetables, which may become contaminated with parasite eggs during the fertilization process, should be scrutinized and washed thoroughly.
"It is becoming more and more of a problem in the United States," Dr. Teale said. "In some areas, health care providers are not used to seeing it and it will take a lot longer to diagnose and treat."
Contact: Will Sansom or Heather Feldman