Helicobacter pylori-associated gastritis is rare in AIDS: antibiotic effect or a consequence of immunodeficiency?

Helicobacter pylori is the principal cause of type B histologic gastritis. AIDS is associated with increased susceptibility to Gram-negative enteric infections. Using a retrospective study design, we have determined the prevalence of H. pylori-associated histologic gastritis (based on gastric histopathology) in 201 patients with AIDS. These data were compared with H. pylori prevalence rates (based on serology) from healthy HIV-negative, age-matched Australian controls (n = 785) and a cohort (n = 137) of HIV-negative, dyspeptic patients undergoing panendoscopy and antral biopsy, at a community endoscopy center. Twenty-five of 201 (12.5%) patients with AIDS had histologic gastritis and, of these, six (25%) had H. pylori. The 3% (six of 201) H. pylori prevalence rate in the AIDS patients was significantly less than age-matched HIV-negative controls (22%) p = 0.001 and endoscopy center controls (59%) p = 0.009. The explanation for this unexpectedly low prevalence of H. pylori is not possible from these data. It may be a consequence of antimicrobial therapy. Other potential explanations may include specific HIV-related host factors, including hypochlorhydria or an inadequate mucosal inflammatory response, which may impair successful colonization of H. pylori.