[Comparative multicenter study of 2 methods of determining sensitivity to antibiotics. Gel diffusion method and...

Susceptibility of 60 bacterial isolates to 15 antibiotics was determined by two methods in three laboratories: 48 Gram negative bacilli and 12 Staphylococci were selected because of "intermediate" susceptibility to at least one antibiotic. Results show a good correlation between the two methods: more than 90% for carbenicillin, cefazolin, cefoxitin, cefamandole, kanamycin, tobramycin, amikacin, erythromycin, pristinamycin and fusidic acid, between 80 and 90% for penicillin G, ampicillin, oxacillin, gentamicin, doxycycline, chloramphenicol, spiramycin and clindamycin, less than 80% for neomycin, tetracycline, minocycline and oleandomycin. Interpretation criteria are different in the two methods for rifampicin, colistin and cotrimoxazole. Between the three laboratories, correlation was 90,3% and 88,6% for disc diffusion method and ABAC system respectively.