CHRONIC COLITIS ASSOCIATED WITH HUMAN-IMMUNODEFICIENCY-VIRUS INFECTION

Objective: A clinical and pathological description of chronic colitis associated with human immunodeficiency virus (HIV) infection. Design: A retrospective case review. Setting: Tertiary referral institution and specialist gastroenterology practice. Patients: A series of six patients with human immunodeficiency virus infection and chronic colitis observed for up to four years. Results: The six patients had chronic diarrhoea for longer than six months, rectal bleeding, abdominal pain and stool leukocytosis. The mucosal pattern on colonoscopy showed diffuse proctocolitis, consisting of contact bleeding, superficial ulcerations, exudates, and/or loss of vascular pattern. Colonic biopsies showed a persisting diffuse colitis characterised principally by a mixed inflammatory cell infiltrate (mononuclear cells and neutrophils) and essentially preserved crypt architecture after six to 39 months of histological follow-up. The histopathology over this time frame was not typical of ulcerative colitis or Crohn's disease, nor of the conventionally described forms of infective colitis. HIV nucleic acid was identified by in-situ hybridisation in colonic biopsies from four patients. In two of three patients tested, the presence of HIV DNA was confirmed by Southern blot analysis. No other microbial agent could be demonstrated as the cause of diarrhoea. At presentation all patients had CD4+ lymphocyte counts greater than 265 x 10(6)/L and none had the acquired immunodeficiency syndrome. Four patients have gone into remission, the other two patients were not in remission at four and a half to five years after onset. Conclusion: We suggest that chronic colitis may represent a new entity related to infection of the colon with human immunodeficiency virus.