PT - JOURNAL ARTICLE AU - Kader, Abdulrahman A. AU - Kumar, Angamuthu K. TI - Prevalence of extended spectrum b-lactamase among multidrug resistant gram-negative isolates from a general hospital in Saudi Arabia DP - 2004 May 01 TA - Saudi Medical Journal PG - 570--574 VI - 25 IP - 5 4099 - http://smj.org.sa/content/25/5/570.short 4100 - http://smj.org.sa/content/25/5/570.full SO - Saudi Med J2004 May 01; 25 AB - OBJECTIVE: To determine the prevalence of extended spectrum b-lactamase (ESBL) among multidrug resistant isolates of enterobacteriaceae and non-fermenting gram-negative bacilli.METHODS: This study was carried out at the Almana General Hospital, Eastern Province, Kingdom of Saudi Arabia, during the period March 2002 through to June 2003. Multidrug resistant gram-negative isolates from patients admitted to the surgical, medical, pediatric, long-term care and intensive care units were studied for the presence of the ESBL enzyme.RESULTS: A total of 3231 gram-negative organisms were studied for the presence of multidrug resistance and ESBLs. Of these, 197 (6%) isolates were multidrug resistant (MDR), and 156 (4.8%) were positive for ESBL. Seventy nine percent of the MDR strains were positive for ESBL. The most frequent isolates were Escherichia coli (1116) and Klebsiella pneumoniae (687) and ESBL was detected in 72 (6.5%) and 37 (5.4%) of these isolates. The MDR strains that produced ESBL were most commonly isolated from surgical care patients with diabetic fascitis (83%) and patients with indwelling Foley's catheter (79%). Extended spectrm b-lactamase producing strains showed the highest susceptibility to imipenem and meropenem (86%). The non-b-lactam antibiotics with greatest activity against these ESBL strains in vitro were ciprofloxacin (72%), amikacin (70%), tobramycin (67%) and gentamicin (56%).CONCLUSION: The majority (79%) of the MDR enterobacteriaceae and non-fermenting gram-negative bacilli tested over 15-months were positive for ESBL. Imipenem, meropenem, ciprofloxacin and amikacin showed the highest activity against these ESBL-producing organisms. Due to the growing problem of infection with ESBL-producing bacteria, which are frequently resistant to many classes of antibiotics resulting in difficult-to-treat infections, clinicians need to be familiar with the clinical significance of these enzymes and potential strategies for dealing with them.