Susceptibility of Pathogenic Bacteria to Amoxicillin/Clavulanic Acid (Augmentin) at a Referral Hospital

Abstract

A total of 957 strains of bacteria isolated from clinical specimens were tested in vitro to determine the efficacy of amoxicillin/clavulanic acid (Augmentin). Sixty-seven percent of the 538 strains of Enterobacteriaceae, 93% of 174 Staphylococcus aureus, and all the 48 isolates of enterococci were inhibited by Augmentin. All the 156 strains of Pseudomonas aeruginosa, P. fluorescens, Enterobacter, Citrobacter, Serratia, and Shigella flexneri were resistant to Augmentin. Augmentin showed considerably increased activity against Escherichia coli, Klebsiella pneumoniae, Proteus species, and staphylococci when compared with ampicillin. Bacteria acquire resistance to penicillin by several different mechanisms. These include alteration of autolysins, transition to L-forms, development of impermeability, and production of enzymes that inactivate the drug.