Objective: To assess the compliance, tolerance and efficacy of a short chemoprophylaxis regimen (IR) for tuberculosis using isoniazid (INH) plus rifampin (RIF) during 3 months versus a standard regimen (I) of isoniazid during 12 months in HIV positive patients.
Material and methods: Prospective, comparative, randomized and open clinical trial in four general hospitals and one prison hospital of Castilla-La Mancha. Prophylaxis was administered to PPD-positive patients and to anergic patients according to the CDC recommendations (1991). Patients were randomized in two treatment groups: regimen IR, isoniazid 300 mg daily and rifampin 600 mg daily; regimen I, isoniazid 300 mg during 12 months.
Results: 133 patients were included, 64 to regimen I and 69 to regimen IR. Regimen IR had a better tolerance with a 28% of adverse effects versus 55% in regimen I. Hepatotoxicity was more frequent in regimen I with a RR = 2.2 (CI 95% 1.23-4.01). Severe hepatotoxicity leading to treatment withdrawal was related to drug administration time and was more frequent in the 12 months regimen group. Short regimen showed a better compliance, without significant differences. Tuberculosis incidence rate was a 4.23 cases/100 persons--year for regimen I and 2.08 in regimen IR, with a relative risk for developing tuberculosis with regimen IR group of 0.51 (CI 95% 0.09-2.8) versus regimen I group, without statistical significance. Prison stay was associated to a significant risk for tuberculosis, regardless of both regimens (RR = 9.2 CI 95%, 1.06-80.2).
Conclusions: In HIV-infected patients with PPD(+) or anergic, regimen with IR is at least as effective as regimen I for preventing the development of tuberculous disease, and has less adverse effects.