RESUMEN
Renew interest and enthusiasm for anaerobes stem from both technological improvements (culture media, production of an adequate anaerobic atmosphere, identification methods) and greater awareness on the part of clinicians. Anaerobic infections were historically treated empirically, targeting the species known to be involved in each type of infection. Prevotella, fusobacteria, and Gram-positive cocci (GPAC) were considered responsible for infections above the diaphragm whereas for intra-abdominal infections, Bacteroides of the fragilis group (BFG), GPAC and clostridia were predominantly implicated. The antibiotic susceptibility of anaerobes was only taken into consideration by the clinician in the event of treatment failure or when faced with infections by multidrug-resistant bacteria (MDR). The evolution of antibiotic resistance together with clinical failures due to the absence of detection of hetero-resistant clones has resulted in a greater need for accessible antibiotic susceptibility testing (AST) and disc diffusion method. Improved isolation and identification of anaerobes, along with the availability of accessible and robust methods for performing AST, will ensure that treatment, whether empirical or guided by an antibiogram, will lead to better outcomes for anaerobic infections.
Asunto(s)
Infecciones Bacterianas , Cocos Grampositivos , Humanos , Farmacorresistencia Bacteriana , Bacterias Anaerobias , Clostridium , Pruebas de Sensibilidad Microbiana , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Infecciones Bacterianas/tratamiento farmacológico , Infecciones Bacterianas/microbiologíaRESUMEN
In vitro susceptibility data were collected for co-amoxiclav and other antimicrobial agents against 1297 recent anaerobe isolates collected in Europe and the USA. The co-amoxiclav (amoxicillin/clavulanic acid) MIC(50/90)s (amoxicillin/clavulanic acid concentration in a ratio of 2:1, expressed in terms of amoxicillin concentration in mg/L) were 0.5/4 for Bacteroides fragilis, =0.125/1 for Prevotella species, =0.125/0.25 for Fusobacterium nucleatum, 0.5/1 for Eikenella corrodens, 0.25/8 for Peptostreptococcus anaerobius, =0.125/0.5 for Micromonas (Peptostreptococcus) micros, =0.25/0.5 for Fingoldia (Peptostreptococcus) magna, and =0.125/0.125 for Porphyromonas species. The co-amoxiclav susceptibility rate for B. fragilis was 94.6%, for P. anaerobius 84.3% and for all other species tested 100%. These data indicate that co-amoxiclav remains an effective drug for the antimicrobial treatment and prophylaxis of many anaerobic infections. Among the comparator drugs, metronidazole was very active against all bacterial species (>96% susceptible) except E. corrodens (MIC(50/90) of >32/>64 mg/L), which is a capnophilic organism. Imipenem was also highly active against all species (>98% susceptible). Levofloxacin and clindamycin were the least potent agents tested, particularly against Bacteroides, Prevotella and Peptostreptococcus (levofloxacin susceptibility rates: Bacteroides 72.7%, Prevotella 71.5%, F. magna 72.4%; clindamycin susceptibility rates: Bacteroides 79.5%, Prevotella 92.1%, F. magna 84.7%).