[The antibacterial efficacy of cefaclor against bacteria resistant to ampicillin, tetracycline and co-trimoxazole (author's transl)].

The antibacterial activity of the new oral cephalosporin cefaclor was investigated using 623 freshly isolated bacterial strains. A high degree of efficacy of cefaclor was noticed against Escherichia coli, Proteus mirabilis and Klebsiella. Nearly all strains which were sensitive to ampicillin, tetracycline and co-trimoxazole were also inhibited by cefaclor. Some of the strains resistant to the three above-mentioned antibiotics were also sensitive to cefaclor as follows: all of ten P. mirabilis strains resistant to co-trimoxazole, 54% of the E. coli strains resistant to ampicillin, tetracycline and co-trimoxazole, and 18% of the Klebsiella strains resistant to tetracycline and co-trimoxazole.