Resistance of anaerobic bacteria to antimicrobial agents in Spain

Abstract

As a consequence of antibiotic consumption, the entire microbial ecosystem attached to man is evolving towards resistance. In Spain, penicillin resistance (MIC > 0.5 mg/l) is found in about 10 % ofPeptostreptococcus, Clostridium perfringens andEubacterium, and in 50 % ofVeillonella. Cefoxitin resistance (> 2 mg/l) is present in 10 to 20 % ofPeptostreptococcus andClostridium, and in 50 % ofEubacterium; 21 % ofBacteroides (fragilis group) strains are resistant to 16 mg/l. A very low rate of imipenem resistance (≥ 128 mg/l) is found amongBacteroides (1 %), but for 5 % of the isolates MICs of imipenem are 2 to 4 mg/l. Metronidazole resistance (> 8 mg/l) is found in 5 to 10 % ofPeptostreptococcus, Clostridium andVeillonella, and in less than 1 % of theBacteroides fragilis group. Erythromycin resistance (> 2 mg/l) is present in over two-thirds of thePeptostreptococcus, Veillonella andFusobacterium isolates, and in 27 % of theClostridium perfringens strains. Clindamycin resistance (> 4 mg/l) is found in 10 to 20 % of thePeptostreptococcus, Clostridium andEubacterium isolates, and in 20 % of theBacteroides of thefragilis group, this rate being higher (30 %) among faecal isolates.