[Incidence of tuberculostatic-resistant Mycobacterium tuberculosis. Clinical aspects and impact on therapy and clinical course].

BACKGROUND

To know the incidence of Mycobacterium tuberculosis resistant to anti-tuberculin drugs in addition to the clinical features, treatment and evolution of the patients.

METHODS

This was a retrospective study of the clinical histories of patients with isolation of Mycobacterium tuberculosis with some type of resistance studied from January 1980 to April 1992.

RESULTS

During the period studied 470 patients were diagnosed with tuberculosis by cultures. In 30 of these cases (6.4%) Mycobacterium tuberculosis resistant to Isoniazide (8), Streptomycin (6), Isoniazide + Rifampicin (4), Isoniazide + Streptomycin (3), Isoniazide + Ethambutol (2), Isoniazide + Rifampicin + Streptomycin (2), Isoniazide + Rifampicin + Ethambutol (2), Rifampicin (1), Ethambutol (1), Isoniazide + Pyrazinamide (1) and Isoniazide + Rifampicin + Streptomycin + Ethambutol (1) were isolated. Clinical information was obtained on 23 patients, with the most frequent clinical pictures being those of respiratory infection (15). Five cases occurred in HIV+ patients. The resistance was considered as primary in 58.97% of the cases with modifications in empiric treatment being necessary in 6 cases. In 15 out of the 19 patients from whom the data of the follow up was obtained the evolution was good.

CONCLUSIONS

Resistance to Mycobacterium tuberculosis was 6.4%, with the high number of strains resistant to Rifampicin being of note. In 79% of the cases in which follow up data was obtained the resistance had no impact on treatment due to the good evolution of the patients in relation with the treatment used.