Abdominal tuberculosis was common in the United Kingdom in the 18th and 19th centuries and in the first half of the 20th century. During the 1950's the recognition of Crohn's disease, the use of streptomycin and other drugs, and the pasteurisation of milk led to the virtual disappearance of abdominal tuberculosis in the western world. During the last two decades a new type, mycobacterium tuberculosis hominis, has appeared mainly in the immigrant population, especially in those from the Indian subcontinent. A retrospective review of 68 patients with abdominal tuberculosis is presented. The pathology, diagnosis and management of these cases is discussed, together with the differential diagnosis of Crohn's disease. It is suggested that the immigrant brings the disease into the United Kingdom in his mesenteric glands and that the disease is reactivated or 'revived' at some later date due to some modification of the immune process.