Hamadan University of Medical Sciences Avicenna Journal of Clinical Microbiology and Infection 2383-0298 1 3 2014 10 01 Prevalence of Extended Spectrum β-Lactamase in Klebsiella pneumonia Isolates in a Teaching Hospital of Zahedan City, Iran 22934 22934 10.17795/ajcmi-22934 EN Mahbobeh Barakzahi Bahman Hormozi Ahmad Rashki Zahra Rashki Ghalehnoo Journal Article 10.17795/ajcmi-22934 2014 08 20 2014 09 16 Background: Extended-spectrum β-lactamase (ESBL)-producing Klebsiella pneumonia has become widespread in hospitals and is increasing in community settings. Most of K. pneumonia that harbor these enzymes, display resistance to other unrelated antimicrobial agents and thus, often pose a therapeutic dilemma. Objectives: This study was conducted to determine the prevalence of ESBL-producing K. pneumonia in a major university hospital in Zahedan, Iran. Materials and Methods: The susceptibility of 83 K. pneumonia isolates to 12 antibiotics was assessed using Kirby-Bauer disc diffusion method. For the ESBL phenotypic test, double-disk diffusion (DD) method was used. Results: The highest resistance rates of the isolates were seen against cefixime (82%), cefotaxime (81%), ceftriaxone (73%), ceftazidime (72%), and azithromycin (60%), consecutively. The lowest resistance rates were observed against gentamicin (58%), tetracycline (59%), nalidixic acid (59%), and amikacin (63%), consecutively. ESBLs were found in 65% of K. pneumonia isolates. Conclusions: We found that 65% of K. pneumonia isolates produced ESBL. Therapeutic strategies to control infections should be carefully formulated in teaching hospitals. The high percentage of drug resistance in ESBL-producing K. pneumonia suggests that routine detection of ESBL by reliable laboratory methods is required.