A retrospective epidemiological study of abdominal tuberculosis in a defined population in the London Borough of Tower Hamlets was conducted between January 1985 and 31 December 1989. The total population of 163,900 included a mean of 20,732 Bangladeshis. Of the 13 cases diagnosed 8 were Bangladeshi, with equal involvement of the peritoneum and intestine. The crude incidence in the Bangladeshi community was 7.7 cases/10(5)/year, which was significantly higher than that in Europeans (0.3 cases/10(5)/year, chi 2 with Yate's correction = 14.0 P < 0.001). The highest age-specific incidence was amongst those aged 16-20 years and 41-45 years. Most patients had a laparotomy or peritoneal biopsy to confirm the diagnosis. The response to therapy was good. Only 62% of cases were notified. This study confirms the importance of tuberculosis in the differential diagnosis of abdominal symptoms in Bangladeshi patients.