Extrapulmonary tuberculosis in a HIV negative population

Abstract

Objective: to analyze the clinical characteristics of patients with extra pulmonary tuberculosis (TB) not infected with human immunodeficiency virus (HIV).

Material and methods: this was a cross-sectional and multi center study in which 324 patients with TB who tested negative for evidence of antibodies to HIV were included. Patients were attended in two third-level hospitals and some primary care centers in the city of Medellín (Colombia), between january of 2000 and december of 2002. Patients with extra pulmonary TB were then compared with those with pulmonary TB.

Results: 89 patients with extra pulmonary TB (27.5%) were analyzed. The main extra pulmonary organs were pleura, lymph nodes, larynx, and genitourinary tract. 11 patients presented with more than one extra pulmonary organ involvement. Patients with extra pulmonary TB were younger than those with pulmonary TB (35.4 ± 16.9 years vs 41.9 ± 16.6 years, p=0.002). Diabetes (OR: 6.34) and family history of TB (OR: 2.2) were associated factors to pulmonary TB but not to extra pulmonary TB. The frequency of patients having a previous BCG vaccination was not different among the two groups. Differences in the percentage of patients having a prior (BCG) vaccination were neither observed between the two studied groups, nor found differences in function of the origin (rural vs urban). The presence of a prior TB was observed in 11% and 5% of the patient with pulmonary and extra pulmonary TB, respectively.

Conclusion: the present study indicates a high rate of extra pulmonary TB in our population; confirms that diabetes and a family history of TB are risk factors for pulmonary TB. BCG vaccination does not seem to protect against the disease. The possibility of both re infection and relapses of TB was clearly observed.