We studied the prevalence of Helicobacter pylori
in patients with leprosy and the effects of co-infection on the immune response to Helicobacter
antigens in the polar groups of leprosy (lepromatous and tuberculoid). We showed that there is no difference in the prevalence of H. pylori
in patients with leprosy as compared to a non-leprosy population. We also demonstrated that the immune response to low molecular weight H. pylori
antigens (35, 26 and 19 kDa) differs in patients with lepromatous as compared to those with tuberculoid leprosy. In lepromatous leprosy, we show that there is a higher prevalence of the 35 and 26 kDa antigens, but a lower prevalence of the 19 kDa antigen. These immunological results are consistent with previous histopathological studies illustrating a more severe gastrointestinal inflammation in lepromatous patients; importantly, a response to the 35 kDa antigen is recognized as a marker for the development of ulcerative disease.