RESUMO
BACKGROUND AND OBJECTIVE: The spread of carbapenem-resistant Klebsiella pneumoniae especially blaNDM-1-carrying isolates is a great concern worldwide. In this study we describe the molecular basis of carbapenem-resistant K. pneumoniae in three teaching hospitals at Bandar Abbas, south of Iran. MATERIALS AND METHODS: A total of 170 nonduplicate clinical isolates of K. pneumoniae were investigated. Antimicrobial susceptibility test was performed by disc diffusion method. PCR was carried out for detection of carbapenemase (blaKPC, blaIMP, blaVIM, blaNDM, blaSPM, blaOXA-48, and blaOXA-181) and extended-spectrum ß-lactamase (blaCTX-M, blaSHV, blaTEM, blaVEB, blaGES, and blaPER). Clonal relatedness of blaNDM-1-positive isolates was evaluated by multilocus sequence typing (MLST). RESULTS: Tigecycline was the most effective antimicrobial agent with 96.5% susceptibility. In addition, 6.5% of the isolates were carbapenem resistant. BlaNDM-1 was identified in four isolates (isolate A-D) and all of them were multidrug-resistant. MLST revealed that blaNDM-1-positive isolates were clonally related and belonged to two distinct clonal complexes, including sequence type (ST) 13 and ST 392. In addition to blaNDM-1, isolate A coharbored blaSHV-11, blaCTX-M-15, and blaTEM-1, isolate B harbored blaSHV-11 and blaCTX-M-15, and isolates C and D contained both blaSHV-1 and blaCTX-M-15. CONCLUSION: Our results indicate that NDM-1-producing K. pneumoniae ST 13 and ST 392 are disseminated in our region. Moreover, one of our major concerns is that these isolates may be more prevalent in the near future. Tracking and urgent intervention is necessary for control and prevention of these resistant isolates.
