title: Susceptibility of anaerobic bacteria to beta-lactam antibiotics in the United States.
abstract: beta-Lactam antibiotics are critical agents in the treatment of anaerobic infections. Susceptibility to these agents, however, varies widely, depending on the specific drug and organism; has not been constant over time; and differs in various geographic locations within the United States for many species. For the organisms in the Bacteroides fragilis group, the beta-lactam antibiotics with the most consistent activity are imipenem and combinations of a beta-lactam drug plus a beta-lactamase inhibitor, such as ticarcillin/clavulanate and ampicillin/sulbactam. Antibiotics with less activity include cefoxitin, piperacillin, cefotetan, and ceftizoxime. In other species of anaerobic gram-negative bacilli, beta-lactamase production is seen with increasing frequency. In vitro susceptibility of these strains is now similar to that of the B. fragilis group, with imipenem, ticarcillin/clavulanate, ampicillin/sulbactam, and cefoxitin being the most active drugs. The anaerobic gram-positive cocci and bacilli remain, for the most part, highly susceptible to penicillins and imipenem.
authors.affiliation: Department of Veterans Affairs Medical Center and The Medical College of Pennsylvania, Philadelphia 19129.
authors.forename: C C
authors.initials: CC
authors.lastname: Johnson
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001421:Bacteria, Anaerobic / Q000187:drug effects* / Q000201:enzymology / Q000302:isolation & purification; D001441:Bacteroides fragilis / Q000187:drug effects / Q000201:enzymology / Q000302:isolation & purification; D002511:Cephalosporins / Q000494:pharmacology; D004352:Drug Resistance, Microbial; D004359:Drug Therapy, Combination / Q000494:pharmacology; D006801:Humans; D066298:In Vitro Techniques; D010406:Penicillins / Q000494:pharmacology; D014481:United States; D065093:beta-Lactamase Inhibitors; D001618:beta-Lactamases / Q000096:biosynthesis
chemical_list: D000900:Anti-Bacterial Agents; D002511:Cephalosporins; D010406:Penicillins; D065093:beta-Lactamase Inhibitors; D001618:beta-Lactamases