Co-occurrence of Carbapenemase-encoding Genes Among Klebsiella pneumoniae Clinical Isolates: Positive Relationship of bla NDM and bla SIM with Imipenem Resistance

Abstract

Background: Carbapenem-resistant Klebsiella pneumoniae (CR-KP), known as a significant public health threat, is the most common causative agent of nosocomial and community-acquired infections. Objectives: This study aimed to evaluate resistance to carbapenems and determine the prevalence of carbapenemase genes and multilocus sequence typing (MLST) of K. pneumoniae clinical isolates. Methods: One-hundred K. pneumoniae isolates were evaluated. The minimum inhibitory concentrations (MIC) of imipenem and meropenem were assessed by the broth microdilution method. Multiplex-polymerase chain reaction (PCR) was applied to detect 11 carbapenemase-encoding genes belonging to different classes. The alleles and sequence types (ST) of three isolates were identified by MLST. Results: The MIC of carbapenems for the isolates ranged from 0.062 to 32 µg/mL. Overall, resistance rates to imipenem and meropenem were reported 11% and 34%, respectively. The bla IMP gene was the most abundant (78.4%), followed by bla OXA-48 (48.6%), bla GIM (27%), bla KPC (27%), bla SIM (21.6%), bla BIC (6.6%), bla NDM (16.2%), bla AIM (16.2%), bla VIM (16.2%), bla DIM (8.1%), and bla SPM (8.1%). The co-existence of carbapenemase genes was observed in 81.8% of the isolates. A positive relationship was found between the presence of bla NDM and bla SIM and resistance to imipenem. Multilocus sequence typing results showed three different sequence types, including ST14, ST5188, and ST1861. Conclusions: This study revealed a high prevalence of CR-KP isolates that suggests a high risk of horizontal gene transfer and potential to spread resistance among other strains. Since STs are reported for the first time in Iran, they can be considered as emerging strains.

Prevalence and molecular determinants of carbapenemase-producing Klebsiella pneumoniae isolated from Jazan, Saudi Arabia

“…Although many previous studies [47][48][49] have reported that bla NDM is the main mechanism of carbapenem resistance in Gram-negative bacteria including K. pneumoniae, this study showed a clear correlation between carrying the bla OXA-48 gene and imipenem resistance (with p values of < 0.014). Consequently, the bla OXA-48 gene may play a significant role in carbapenem resistance, but other factors such as deficiency or decreased expression of porins and increased activity of bacterial efflux pump need to be considered.…”

Bacterial Resistance in Hospital-Acquired Infections Acquired in the Intensive Care Unit: A Systematic Review

“…The results obtained among KPC producing K. pneumoniae also reflect the well-known dominance of ST258 clone in USA (100). Multilocus sequence typing in carbapenem-resistant K. pneumoniae strains showed that ST15 was prevalent in Portugal (4), ST395 in France (69), ST11 in China (106,107), and ST14, ST5188, ST1861 in Iran (98).…”

“…The most frequent antibiotic resistance genes, such as genes coding the production of ESBL, are located in plasmids. Recent studies point to plasmid-mediated transfer in hospitals in Africa (17, 19, 25-28, 33, 52, 101), Asia (35,40,42,45,57,94,98,105), Latin America (63-65), Europe (67,72,91), and North America (89,100,103).…”

Assessment of the activity of tigecycline and colistin on biofilm producer Klebsiella pneumoniae isolated from COVID-19 patients, Iran

“…However, the overuse of carbapenems in hospitals has led to an increase in Carbapenem-Resistant Klebsiella pneumoniae (4). Klebsiella pneumoniae carbapenemase (KPC)-producing is becoming distressing (5). Several mechanisms result in resistance to carbapenems, including the production of carbapenemases of class A (KPC, GES, and others), class B (mainly IMP, VIM, or NDM), and class D (OXA-48) and related enzymes.…”