Prevalence of antimicrobial resistance among gram-negative isolates in an adult intensive care unit at a tertiary care center in Saudi Arabia

BACKGROUND AND OBJECTIVES Patients in the ICU have encountered an increasing emergence and spread of antibiotic resistant pathogens We examined patterns of antimicrobial susceptibility in gram negative isolates to commonly used drugs in an adult ICU at a tertiary care hospital in Riyadh Saudi Arabia METHODS A retrospective study was curled out of gram negative isolates from the adult ICU of King Fah-id National Guard Hospital (KFNGH) between 2004 and 2009 Organisms were identified and tested by an automated identification and susceptibility system and the antibiotic susceptibility testing was confirmed by the disk diffusion method RESULTS The most frequently isolated organism as Acinetobacter baumannii followed by Pseudomonas aeruginosa Escherichia coli Klebsiella pnemoniae Stenotrophomonas maltophilia and Enterobacter Antibiotic susceptibility patterns significantly declined in many organisms especially A baumannii E coli S marcescens and Enterobacter A baumannii susceptibility was significantly decreased to imipenem (55% to 10%) meropenem (33% to 10%) ciprofloxacin (22% to 10%) and amikacin (12% to 6%) E coli susceptibility was markedly decreased (from 75% to 50% or less) to cefuroxime ceftazidime cefotaxime and cefepime S marcescens susceptibility was markedly decreased to cefotaxime (100% to 32%) ceftazidime (100% to 35%) and cefepime (100% to 66%) Enterobacter susceptibility was markedly decreased to ceftazidime (34% to 5%) cefotaxime (34% to 6%) and pipracillin tazobactam (51% to 35%) Respiratory samples were the most frequently indicative of multidrug resistant pathogens (63%) followed by urinary samples (57%) CONCLUSION Antimicrobial resistance is an emerging problem in the KFNGH ICU justifying new more stringent antibiotic prescription guidelines Continuous monitoring of antimicrobial susceptibility and strict adherence to infection prevention guidelines are essential to eliminate major outbreaks in the future