Antibiotic Susceptibility Profile of Carbapenem-Resistant Klebsiella pneumoniae Isolated from Clinical Specimens in Iraq

Background: Infections caused by carbapenem-resistant Klebsiella pneumoniae (CR-Kp) isolates are a major threat to public health. Antibiotic misuse and overuse lead to the emergence of CR-Kp. Objectives: This study investigated the distribution and phenotypic virulence factors of CR-Kp isolates. Materials and Methods: The specimens were collected from 1029 patients from major hospitals in Babylon City. K. pneumoniae was diagnosed based on biochemical characteristics and the Vitek 2 compact system. Antibiotic susceptibility patterns and biofilm formation by CR-Kp were also investigated. Results: This study found that 66 isolates belonged to K. pneumoniae , 14 of which belonged to (CR-Kp). It was found that 5/14 (35.72%) of urine samples were CR-Kp, 4/14 (28.57%) from burns were CR-Kp, and 1/14 (7.14%) were from diabetic foot. Results also showed that all CR-Kp isolates were highly resistant to most of the antibiotics tested, while they showed a lesser degree of resistance to nitrofurantoin, tigecycline, colistin, gentamicin, and trimethoprim-sulfamethoxazole. The results showed that 54 (81.82%) of all 66 K. pneumoniae isolates were multidrug-resistant, nine (13.63%) were extensively drug resistant, and three (4.55%) were pan-drug resistant. The results of biofilm formation showed that 11 (78.57%) isolates had a strong biofilm formation capacity, moderate biofilm was shown in two (14.29%) isolates, and one (7.14%) isolate showed no biofilm formation. The results also showed that 11 (78.57%) of the isolates were hypermucoviscous phenotypes. Conclusion: A high percentage of CR-Kp isolates were from wounds. They were resistant to most antibiotics. Most of the CR-Kp isolates have moderate to high degrees of viscosity, and a high percentage of CR-Kp isolates have a strong capacity for biofilm formation. Colistin and tigecycline antibiotics are the most effective against CR-Kp isolates.