[Streptomycin as second-line chemotherapy for tuberculosis].

Streptomycin was the first antibiotic to be used against Mycobacterium tuberculosis. It was used for years in monotherapy regimens, thereby resulting in the appearance of resistance and the relegation of its use. The resistance detected against drugs currently employed has led to a renewed interest in streptomycin. Its mechanism of action is centered on the ribosome, inhibiting the protein synthesis of the microbacteria. Resistance appears when mutations in the genes codifying for rRNA 16S and for protein S12 are produced. We studied the use of streptomycin against 899 M. tuberculosis strains, 713 of which were from pulmonary and 186 from extrapulmonary isolates. The BACTEC 460 TB system was initially employed as was the ESP II system. As controls, the ATCC27294 pattern strains (susceptible to streptomycin, rifampicin, ethambutol and isoniazid) were used. The results showed 2.1% secondary resistance in all the cases. Multiresistance was observed in 12 strains.