Prévention de la résistance à la rifampicine par le pyrazinamide dans la tuberculose expérimentale de la souris.

The capacity of Pyrazinamide (PZA) to prevent the selection of Rifampicin (RMP) resistant mutants was tested by the intravenous innoculation of 160 mice with 2 X 10(6) c.f.u. of M. tuberculosis, and two weeks later, the treatment of the mice either with 10 mg/kg/day RMP alone or with RMP + PZA 150 mg/kg/day. After three months of treatment, lungs and spleen were culture positive in respectively 95% and 90% of the mice treated with RMP alone and in 37% and 24% of the mice treated by RMP + PZA (p less than 10(-5). The strains isolated from lungs and spleen were resistant to Rifampicin in respectively 87% and 75% of the mice treated with RMP alone and in none of those treated with RMP + PZA.