[Comparative antibacterial activity of cefpodoxime, cefuroxime and cefaclor against strict anaerobic bacteria]

The in vitro activity of a new cephalosporin (CPX) was assessed against 260 strains of anaerobic bacteria. A comparison was done with two other oral cephalosporins cefaclor (CFA) and cefuroxime (CXM). MICs were determined by an agar-dilution method on wilkins chalgren agar. The three antibiotics had little activity against Bacteroïdes fragilis group. Cefpodoxime was more active than the two other cephalosporins against Fusobacterium and Bacteroïdes spp. At 4 mg/l concentration the percentages of susceptibility were respectively CFA 8% CXM 11% for all the Gram negative bacilli. Inversely, a better activity was detected against Gram positive anaerobes; the three cephalosporins inhibiting respectively CFA 65% CXM 75% CFX 46% of 94 tested strains. All Veillonella spp. and Propionibacteria were inhibited by cefpodoxime 4 mg/l. The activity of the three cephalosporins were similar weak against Gram negative anaerobes but greater against Gram positive strict anaerobes.