Evaluation of Antibiotic Resistance Pattern and Efficacy of Modified Hodge Test for Detection of Carbapenem-Resistant Klebsiella pneumoniae Strains Isolated From Clinical Samples

Background: Klebsiella pneumoniae is a gram-negative opportunistic pathogen that causes different infections, however, in recent years the emergence of resistance to carbapenem antibiotic among these isolates has caused failure in the treatment of these infections. Objective: The aim of this study was to evaluate the prevalence of carbapenemase-producing K. pneumoniae strains among various clinical specimens obtained from different wards of Isfahan hospitals, Iran. Materials and Methods: In this cross-sectional study, 100 different clinical samples were collected from different wards of teaching hospitals in Isfahan, Iran. K. pneumonia isolates were identified by different standard biochemical tests. Antimicrobial susceptibility tests were performed as standard disk-diffusion based on the instructions of the Clinical Laboratory Standards Institute (CLSI). For detection of K. pneumoniae carbapenemase (KPC)-producing strains, isolates were investigated by the modified Hodge test (MHT) based on CLSI instructions. Results: The study population included 62 females and 38 males (P = 0.01). The highest and the lowest rates of resistance were observed for piperacillin (84%) and ertapenem (50%), respectively. The MHT was positive for 68 (68%) isolates from which the highest rates of resistance were observed for piperacillin (91.2%) and cefotaxime (83.8%). Conclusion: This study demonstrated high prevalence of carbapenemase-producing K. pneumoniae isolates, which shows an urgent need to review and modify the pattern of antibiotic consumption. In addition, in future studies genotypic methods for all carbapenemase genes should be employed to determine the cause of the resistance.