HUMORAL AND CELLULAR-IMMUNITY IN HIV-POSITIVE AND HIV-NEGATIVE HELICOBACTER-PYLORI INFECTED PATIENTS

The prevalence of H. pylori associated gastritis seems to be different in HIV positive and HIV negative patients. Therefore a correlation to immunodeficiency can be postulated. The histology of gastritis, statu s of H. pylori infection and parameters of humoral and cellular immune response were investigated in 41 HIV positive and 47 HIV negative pat ients, who were subjected to upper endoscopy for the evaluation of gas trointestinal symptoms. In HIV positive patients 37% had active chroni c gastritis against 62% of the HIV negative patients. In 73% of HIV po sitive cases of active chronic gastritis H. pylori was detected by bac teriological culture and/or Warthin-Starry stain. In HIV negative pati ents active chronic gastritis was always associated to H. pylori infec tion. Production of antibodies as measured by two commercially availab le ELISA tests was significant in HIV positive and HIV negative patien ts; both tests correlated well with H. pylori detection by culture or direct microscopy. Immunoglobulin class specific immunoblots correspon ded to the ELISA results in HIV negative patients but to a lesser exte nt in the HIV positive group which was assumed to be related to unspec ific polyclonal activation in these patients. Systemic cellular immuni ty was investigated by proliferation assays of peripheral blood mononu clear cells (PBMC). Proliferative response to the unspecific mitogen P HA was reduced in HIV positive patients. A sonicated H. pylori antigen failed to induce lymphocyte proliferation. The antimitogenic effect w as also seen in case of coincubation with PHA. This observation was in dependent of H. pylori and HIV infection status. We conclude that in H IV positive as in HIV negative patients active chronic gastritis is pr edominantly related to H. pylori infection. The prevalence of H. pylor i associated gastritis in HIV positive patients is significantly reduc ed (p < 0.025) compared to HIV negative controls. Decreased susceptibi lity to H. pylori infection in HIV positive patients may not be explai ned by the abnormal reactivity of their humoral or cellular immune res ponse.