title: Cefaclor: in vitro spectrum of activity and beta-lactamase stability.
abstract: The in vitro activity of cefaclor against 556 clinical isolates of gram-positive and gram-negative bacteria was compared with that of other cephalosporins. Cefaclor had activity similar to that of cephalexin against gram-positive bacteria. It showed greater activity against Haemophilus strains than did cephalexin and inhibited beta-lactamase-producing Haemophilus isolates. Cefaclor was more active than cephalexin or cephalothin against Escherichia coli, Salmonella, and Shigella isolates but did not act against Serratia, Acinetobacter, indole-positive Proteus, or Bacteroides isolates. Cefaclor was resistant to type III (TEM) beta-lactamases but was destroyed by type I beta-lactamases and, to a lesser degree, by type IV and type V beta-lactamases.
mesh_terms: D000581:Amidohydrolases / Q000378:metabolism*; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001419:Bacteria / Q000187:drug effects* / Q000201:enzymology; D002510:Cephalosporinase / Q000378:metabolism*; D002511:Cephalosporins / Q000378:metabolism / Q000494:pharmacology*; D004355:Drug Stability; D008826:Microbial Sensitivity Tests
chemical_list: D000900:Anti-Bacterial Agents; D002511:Cephalosporins; D000581:Amidohydrolases; D002510:Cephalosporinase