Trends in bacterial susceptibility to antimicrobial agents.

Concern over the development of drug resistance by common pathogens has grown over recent years. In order to discover and describe possible trends at this institution, susceptibility data for 18 organisms and 21 antimicrobial agents for the years 1975 through 1982 at the Veterans Administration Medical Center in Oklahoma City were reviewed. Summaries of susceptibility data for 64 major combinations of drugs and organisms are presented. Two gram-positive organisms (enterococcus group D and Staphylococcus aureus) as well as a gram-negative (Pseudomonas aeruginosa) appear to be decreasing in susceptibility to several drugs. However, some gram-negative bacilli (Proteus, Serratia, and Enterobacter spp. and Klebsiella pneumoniae) showed evidence of markedly increasing susceptibility to certain drugs.