Objectives: To assess the temporal trends in incidence of tuberculosis (TB) in HIV-infected patients, to evaluate the impact of pulmonary TB on the Centers for Disease Control and Prevention (CDC) 1993 AIDS case definition and to assess the frequency of Mycobacterium tuberculosis strain resistance.
Design: A retrospective study within a cohort.
Setting: The Bordeaux University Hospital and three general hospitals in Aquitaine, southwest France.
Subjects: Since 1985, HIV-infected in- and outpatients aged > 13 years have been included in the Aquitaine cohort. Reported cases of pulmonary and extrapulmonary TB were investigated and records cross-referenced with the files of the TB reference laboratory.
Results: As of 30 June 1993, the Aquitaine cohort (3119 patients) accounted for 6409 person-years (PY) of follow-up. TB was diagnosed in 139 patients (average annual incidence, 2.17 per 100 PY) of whom 79 had bacteriological diagnosis, 13 histological diagnosis and 47 clinical and/or radiological diagnosis. Extrapulmonary TB accounted for 40% of the cases. Intravenous drug use was more frequent in the group who developed TB (50%) than in the rest of the cohort (40%) (P = 0.009). There was an increase in the incidence rate of TB in the cohort between 1985 (0.45 per 100 PY) and 1989 (2.67 per 100 PY) and a stabilization around 1.5-2.0 per 100 PY until 1993. Pulmonary TB was estimated to increase the AIDS cumulative incidence by 0.4% when performing a simulation with the 1993 AIDS case definition. Single drug resistance was documented in 3.4% of the cases and a multiple drug resistance in 5.1%.
Conclusion: TB incidence has stabilized since 1990 in the Aquitaine cohort with a limited increase of the number of AIDS cases (1993 CDC criteria). Drug resistance was rare.