IN-VITRO ACTIVITY OF CEFDINIR (FK482) AND 10 OTHER ANTIBIOTICS AGAINST GRAM-POSITIVE AND GRAM-NEGATIVE BACTERIA ISOLATED FROM ADULT AND PEDIATRIC-PATIENTS

The in vitro activity of cefdinir, an oral aminothiazolyl hydroxyimino cephalosporin was compared with that of cefixime, cefpodoxime, cefaclor, cephalexin, ciprofloxacin, ofloxacin, oxacillin, ampicillin, vancomycin and trimethoprim-sulfame-thoxazole against 279 gram-positive and gram-negative recent clinical isolates from adult and pediatric patients. Cefdinir was the most active drug among the cephalosporins against oxacillin-sensitive Staphylococcus aureus and coagulase-negative staphylococci, Streptococcus pneumoniae, S. pyogenes, Escherichia coli and Moraxella catarrhalis (MIC(90) 0.015-2 mg/l). Cefixime was the most active agent against Hemophilus influenzae, Klebsiella pneumoniae, K: oxytoca, Proteus mirabilis and II vulgaris (MIC(90) < 0.015-0.125 mg/l). The activity of cefpodoxime was better than that of cefixime against S. pneumoniae and oxacillin-sensitive staphylococci (MIC(90) 0.25-8 vs. 0.5-32 mg/l), similar to cefixime against S. pyogenes (MIC(90) 0.06 mg/l) and not as good as cefixime against H. influenzae, M. catarrhalis, Klebsiella spp. and Proteus spp. (MIC(90) < 0.015-0.25 vs. 0.125-0.5 mg/l). The activity of cefdinir was greater than that of the other cephalosporins against Enterococcus faecalis (MIC(90) 16-32 vs. > 64 mg/l). None of the cephalosporins were active against methicillin-resistant, coagulase-positive or -negative staphylococci or Pseudomonas aeruginosa (MIC(90) > 64 mg/l). Overall, the susceptibilities of adult and pediatric isolates were similar. Kinetic kill curves demonstrated rapid and similar killing at 6 h by cefdinir, cefixime, cefpodoxime and ofloxacin. At 24 h at 1 x MIC, the least regrowth was observed with cefdinir and cefpodoxime; at 2 x MIC, suppression of growth was similar with all four drugs.