High prevalence of multidrug-resistant non-fermentative Gram-negative bacilli harboring bla and bla metallo-beta-lactamase genes in Birjand, south-east Iran

Abstract

Background and Objectives: Non-fermentative Gram-negative Bacilli (NFGNB) is known as a major cause of health- care-associated infections with high levels of antibiotic resistance. The aim of this study was to investigate the antibiotic resistance profiles and molecular characteristics of metallo-beta-lactamase (MBL)-producing NFGNB.
 Materials and Methods: In this cross-sectional study, the antibiotic resistance profile of 122 clinical NFGNB isolates was determined by the Kirby-Bauer disk diffusion and microdilution broth methods. Bacterial isolates were investigated for the detection of MBLs production using the combination disk diffusion Test (CDDT). The existence of bla , bla , and bla NDM genes in all carbapenem-resistant isolates was determined employing polymerase chain reaction (PCR) assays.
 Results: High resistance in Pseudomonas aeruginosa was reported to cefotaxime and minocycline, whereas Acinetobacter baumannii isolates were highly resistant to all antibiotics except colistin. Multidrug resistance (MDR)-NFGNB (66% vs. 12.5%, P=0.0004) and extensively drug resistant (XDR)-NFGNB (55.7% vs. 12.5%, P=0.001) isolates were significantly more common in hospitalized patients than in outpatients. The production of MBL was seen in 40% of P. aeruginosa and 93.3% of A. baumannii isolates. It was found that 33.3% and 46.7% of carbapenem-resistant P. aeruginosa isolates, and 13.3% and 28.9% of carbapenem-resistant A. baumannii isolates were harboring bla IMP-1 and bla VIM-1 genes, respectively. The incidence of MDR (98.2% vs. 28.3%, P<0.001) and XDR (96.4% vs. 11.7%, P<0.001) in MBL-producing NFGNB isolates was significantly higher than non-MBL-producing isolates.
 Conclusion: This study demonstrated a higher rate of resistance among NFGNB isolates with an additional burden of MBL production within them, warranting a need for robust microbiological surveillance and accurate detection of MBL producers among the NFGNB.

Molecular Characterization Of Non-Fermenting Gram-Negative Bacilli And Its Virulence Markers From Various Clinical Samples In A Tertiary Care Center, South India

“…This was similar to the study by al charrakh et al, were P. aeruginosa was a predominant pathogen among various NFGNB [15]. In our study, P. aeruginosa showed increased prevalence the blaNDM gene (50%) followed by blaVIM gene (25%) and blaIMP gene (25%), these findings were similar to the study by Namaei et al, blaNDM gene (40%) followed by blaVIM gene (29%) and blaIMP gene (13%) [16,17]. In our study, for A. baumannii we observed an increased prevalence of blaOXA-23 gene(78%) followed by blaOXA-58 (56%) and blaNDM gene(33%).…”

Phenotypic and genotypic detection of resistance mechanisms in carbapenem-resistant Gram-negative bacteria isolated from Egyptian ICU patients with first emergence of NDM-1 producing Klebsiella oxytoca

“…However, a lower percentage of MBL prevalence was reported by Gupta et al ( 38 ) (21.4%). Furthermore, a higher percentage of MBL producers (80%) was reported by Namaei et al ( 39 ). In our study, the highest rate of MBL producers was observed in P. aeruginosa ( Table 4 ).…”

Emergence of Multidrug-Resistant Non-Fermenting Gram-Negative Bacilli in a Tertiary Care Teaching Hospital of Central India: Is Colistin Resistance Still a Distant Threat?

“…For colistin broth microdilution, Pseudomonas aeruginosa ATCC 27853 (MIC: 0.5-4 µg/mL) was used as negative control and an in-house Pseudomonas aeruginosa (MIC >16 µg/mL) was used as positive control. The isolates resistant to three or more antibiotic classes were labelled as MDR phenotype [ 19 ]. Descriptive analysis of all the observations is performed.…”