Factors determining ethnic differences in the incidence of bacteriologically confirmed genitourinary tuberculosis in south east England.

In South East England, genitourinary (GU) tuberculosis is a much less common manifestation of non-respiratory tuberculosis in patients of Indian subcontinent (ISC) ethnic origin than in those of European ethnic origin. When considered in relation to all bacteriologically confirmed cases of tuberculosis, both respiratory and non-respiratory, the ethnic difference in the occurrence of GU tuberculosis is much less evident, while there is a highly significant excess of other forms of non-respiratory tuberculosis among the ethnic ISC patients. Unlike other forms of non-respiratory tuberculosis, GU disease tends to occur in an older age range in the ethnic ISC population and, when stratified for age, the ethnic difference in the occurrence of this form of tuberculosis is not significant while that of lymph node tuberculosis remains significantly high. Thus, after elimination of the confounding factor of age, the occurrence of GU tuberculosis is very similar in the two ethnic groups while other forms of non-respiratory tuberculosis differ considerably.