A steady rise in autoimmune diseases such as multiple sclerosis (MS) has been noted in recent decades, and environmental factors could be the cause of this increase. One theory, similar to the "hygiene hypothesis" in which an excessively germ-free environment may contribute to an increase in allergies, holds that a decline in infectious diseases may play a role in increasing autoimmune disease incidence. The first study examining the relationship between parasite infections and MS in humans suggests that such infections may affect the immune response in a way that alters the course of MS. The study was published in the January 2007 issue of Annals of Neurology (http://www.interscience.wiley.com/journal/ana
), the official journal of the American Neurological Association.
Previous studies involving animals have shown that parasite infection can influence the course of autoimmune diseases. These studies suggest that individuals with parasite infections have a diminished T cell response when unrelated antigens (foreign substances that generate an immune response) are present. The current study, conducted by Jorge Correale, M.D., and Mauricio Farez, B.Sc., of the Raúl Carrea Institute for Neurological Research in Buenos Aires, Argentina, involved 12 patients with MS who also had a parasite infection, 12 controls with MS who were uninfected, and 12 healthy individuals. The two groups of MS patients had a similar disease course. Patients had a neurological exam every three months and a brain MRI every 6 months, while immunological evaluations were conducted during the last 12 to 18 months of the study. Patients were followed for an average of 4.6 years.
During the study period, there were three clinical relapses of MS in the infected group and 56 relapses in the uninfected group. Only two infected patients showed minimal Expanded Disability Status Score changes (EDSS is used to measure disability Page: 1 2 Related biology news :1
Source:John Wiley & Sons, Inc.
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