Low prevalence of Helicobacter pylori in individuals with HTLV-I infection

Background The prevalence of Helicobacter pylori in HIV-positive individual s is significantly lower than in HIV-negative controls, However, its preval ence in individuals infected with human T-cell leukaemia virus type I (HTLV -I), another important member of the human retrovirus family, has not been previously investigated. Objective To establish the prevalence of H. pylori in HTLV-I-positive indiv iduals in the Nagasaki Prefecture, which is an area endemic for HTLV-I. Methods We examined sera from 146 HTLV-I-positive individuals with a mean a ge of 56.7 years, consisting of 45 adult T-cell leukaemia (ATL) patients, 1 3 HTLV-I-associated myelopathy (HAM) patients and 88 healthy carriers. Seru m samples of 292 age- and sex-matched HTLV-I-negative controls were also ex amined. Serum anti-H. pylori immunoglobulin (Ig) G antibody was examined us ing an enzyme-linked immunosorbent assay kit. Twenty-eight HTLV-I-positive patients were examined endoscopically, assessed for H. pylori by culture, h istology and CLO test using gastric biopsy specimens, and gastritis in thes e patients was also graded histologically. Results The seroprevalence of H. pylori was 48% in HTLV-I-positive individu als versus 64% in HTLV-I-negative controls (P < 0.01). In the three HTLV-I- positive groups, ATL patients and carriers had significantly lower seroprev alence of H. pylori than the HTLV-I-negative controls (P < 0.05), Assessmen t of H. pylori using gastric biopsy specimens also showed a significantly l ower prevalence of H. pylori infection in HTLV-I-positive patients than con trols (46% versus 70%, P < 0.05). Histological examination showed a signifi cantly higher degree of activity, inflammation and glandular atrophy in the antrum and corpus in H. pylori-positive patients compared to H. pylori-neg ative patients. H. pylori-positive patients with HTLV-I infection had a mor e severe degree of glandular atrophy in the corpus than H. pylori-positive controls without HTLV-I infection. Conclusion We have found a reduced prevalence of H. pylori in HTLV-I-positi ve individuals. Whatever the explanation, infection with HTLV-I does not pr edispose to the risk of H. pylori infection. fur J Gastroenterol Hepatol 11 :497-502 (C) 1999 Lippincott Williams & Wilkins.