[Comparative in vitro activity ampicillin, cefoperazone, their combinations with sulbactam, as well as that of other antibiotics against aerobic gram-negative microorganisms].

The activity of 12 antibiotics against 849 strains of gram-negative aerobes isolated in special and general hospitals of Moscow and Smolensk in 1992-1993 was assayed with the method of serial microdilutions. By the criteria of the activity (percentage of the susceptible strains by the NSSLS criteria) against the isolates the antibiotics were arranged as follows: ciprofloxacin (89.8 per cent) > imipenem (89.6 per cent) > cefoperazone + sulbactam (86.1 per cent) > amikacin (83.8 per cent) > ceftazidime (81.8 per cent) > ceftriaxone (71.1 per cent) > cefoperazone (70.9 per cent) > cefotaxime (70.9 per cent) > gentamicin (60.8 per cent) > ampicillin + sulbactam (44.7 per cent) > cefazolin (37.5 per cent) > ampicillin (23.0 per cent). The frequency of the antibiotic susceptible isolates in the special hospitals was lower at the average by 20 per cent than that in the general hospitals with respect to all the antibiotics assayed.