Antimicrobial resistance of bacterial pathogens at two tertiary-care centers, in Riyadh and Texas.

Antimicrobial resistance of bacterial pathogens usually varies from one geographic location to another. During the last 20 years, outbreaks of disease caused by multiresistant bacteria have occurred with higher frequency in developing countries. We investigated the antimicrobial resistance patterns of bacteria isolated in 1992 from two tertiary-care centers, in Riyadh and Texas. Of the 8841 strains used, 5318 were isolated from clinical specimens of patients at King Faisal Specialist Hospital and Research Centre, Riyadh, and 3523 were from Olin E. Teague Veterans Medical Center, Temple, Tex. Members of Enterobacteriaceae at the King Faisal hospital were significantly more resistant to frequently prescribed antimicrobials than were those at the Olin Teague center. Susceptibility to less frequently used agents like ciprofloxacin and ceftazidime was similar at both hospitals. Resistance patterns of Pseudomonas aeruginosa, Haemophilus influenzae, and coagulase-negative staphylococci were similar at both medical centers. The Olin Teague center encountered significantly more methicillin-resistant Staphylococcus aureus and vancomycin-resistant enterococci.