Susceptibility in vitro of gram-positive aerobe and anaerobe bacteria to ofloxacin.
Ofloxacin is a new fluoroquinolone derivative active against Gram-positive and Gram-negative bacteria including obligate anaerobes. In this study the in vitro activity of ofloxacin was evaluated against 325 Gram-positive organisms freshly isolated from clinical specimens, in comparison with that of ampicillin, erythromycin, clindamycin and ceftazidime. Susceptibility tests indicated that the MIC90 was 2 mg/l (range 0.25-2) against both methicillin-susceptible (MS) and methicillin-resistant (MR) Staphylococcus aureus. A value of 2 mg/l (range 0.5-4) was also found for all other staphylococci. The MIC of ofloxacin was 8 mg/l for 90% of Streptococcus faecalis (range 1-16), Str. faecium (range 2-8) and members of JK group (range 0.5-16). Propionibacterium acnes strains were all inhibited by 2 mg/l and 90% of Clostridia spp. (range 2-16) by 8 mg/l. Ofloxacin activity compared favourably with that of ampicillin, erythromycin, clindamycin and ceftazidime determined on the same isolates. MBC and time-kill studies indicated that this compound is rapidly bactericidal against enterococci. The great intrinsic activity against MS and MR staphylococci, refractory enterococci and JK bacteria may make ofloxacin a useful adjunct to the therapeutic arsenal.
Debbia
E
E
Mannelli
S
S
Gianrossi
G
G
Schito
G C
GC
D000667:Ampicillin / Q000494:pharmacology; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D002442:Ceftazidime / Q000494:pharmacology; D002981:Clindamycin / Q000494:pharmacology; D004917:Erythromycin / Q000494:pharmacology; D006094:Gram-Positive Bacteria / Q000187:drug effects*; D006801:Humans; D008826:Microbial Sensitivity Tests; D015242:Ofloxacin; D010078:Oxazines / Q000494:pharmacology*
D000900:Anti-Bacterial Agents; D010078:Oxazines; D002981:Clindamycin; D004917:Erythromycin; D000667:Ampicillin; D002442:Ceftazidime; D015242:Ofloxacin