Short-Course Isoniazid and Rifampin Compared With Isoniazid for Latent Tuberculosis Infection: A Randomized Clinical Trial.

The objective of the study was to compare the compliance and the side effects of a short course to treatment of latent tuberculosis infection during 3 months with the standard course for 6 months.

Methods: Prospective, comparative, randomized and open trial of patients with positive TST and the suitable criteria for treatment, in accordance with the guidelines of the CDC, excluding HIV infection. the group I was assigned to isoniazid (H) at a dose of 300 mg per day for 6 months and the group II was assigned to isoniazid at a dose of 300 mg per day plus rifampin (R) (600 mg per day) for 3 months. The patients were followed for five years.

Results: 105 patients were included, of which 9 refused the treatment; 45 patients were included in the group I and 51 patients in the group II. Both groups were comparable at base level. The hepatotoxicity was 44% in the group 6H and 29% in the group 3HR (p = 0,07). The hepatotoxicity was severe in 6.7% in the group 6H and 5.8% in the group 3HR; these obliged the suspension of treatment in 4.4% and 1.9%, respectively (p =NS). The proportion of patients who completed the study treatment was 75.6% of the patients in the group 6H, and 90.2% in the group 3HR (p = 0,05). Only a case of tuberculosis was detected in the second month treatment with 6H.

Conclusion: In the treatment of latent tuberculosis infection, a short course with isoniazid plus rifampin during 3 months shown better compliance with a lower percentage of abandonment that the course 6H. Tolerance is similar in the two courses.