Short-course isoniazid and rifampin compared with isoniazid for latent tuberculosis infection: A randomized clinical trial

Introduction. The aim of this study was to compare the adherence to, and side effects of a 3-month short-course treatment for latent tuberculosis infection as compared to the standard 6-month course. Methods. Prospective, comparative, randomized, open trial including patients with a positive tuberculin skin test and appropriate criteria for treatment in accordance with the CDC guidelines, and excluding patients with HIV infection. Group I (6H) was assigned to isoniazid 300 mg per day for 6 months and Group II (3HR) was assigned to isoniazid 300 mg per day plus rifampin 600 mg per day for 3 months. The patients were followed up for five years. Results. A total of 105 patients were included, among which 9 refused treatment; 45 patients were placed in Group I and 51 patients in Group II. Both groups were comparable at baseline. Hepatotoxicity was 44% in Group 6H and 29% in Group 3HR (P 5 0.07). Hepatotoxicity was severe in 6.7% of Group 6H and 5.8% of Group 3HR, requiring treatment interruption in 4.4% and 1.9%, respectively (P 5 NS). Among the total, 75.6% of patients in group 6H, and 90.2% in group 3HR completed the study treatment (P 5 0.05). Tuberculous disease was detected in only one patient in the 6H group, occurring in the second month of treatment. Conclusion. In the treatment of latent tuberculosis infection, a 3-month course of isoniazid plus rifampin resulted in better adherence and a lower percentage of discontinued treatments than a 6-month isoniazid course. Tolerance was similar in the two regimens (AU)