Magnitude of Extended-spectrum Beta-lactamase, AmpC Beta-lactamase and Carbapenemase producing gram negative bacilli isolated from clinical specimens at International Clinical Laboratories, Addis Ababa, Ethiopia
No Thumbnail Available
Date
2018-10
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Addis Ababa University
Abstract
Background: In Gram negative pathogens, beta-lactamase (β-lactamases) production remains the most important mechanism of antimicrobial resistance. These β-lactamases includes Extended spectrum Beta-lactamases (ESBL), AmpC β-lactamases (AmpC) and Carbapenemases.
Objective: To determine the Magnitude of ESBL, AmpC β-lactamases and Carbapenemase producing gram negative bacilli (GNB) isolated from clinical specimens at International Clinical Laboratories, Addis Ababa, Ethiopia.
Methods: A cross sectional study was carried out on 338 GNB isolates between January to May 2018. The bacteria were isolated from urine, wound, body fluids, sputum, stool, ear and eye discharge using 5% sheep blood agar, MacConkey, Xylose lysine deoxycholate and chocolate agar plates. Bacterial species identification, antimicrobial susceptibility testing and β-lactamases screening were performed using Phoenix system. Potential carbapenemase producers were confirmed by Modefied Hodge test and KPC, MBL, OXA-48 were phenotypically characterized by disc diffusion method. Cefoxitin resistant bacteria were confirmed for AmpC β-lactamases production by AmpC confirmatory disc. ESBLs production was confirmed using a combination disc method. Data was entered and analyzed using SPSS version 20 software.
Results: The predominant GNB was E. coli 66.0% (n=224) followed by K. pneumoniae 12.1% (n=41). The magnitude of β-lactamases producing GNB was 43.0% (n=144). The overall magnitude of ESBL producing GNB was 38.8% (n=131) while, carbapenemase and AmpC β-lactamases producing GNB were 1.2% (n=4) and 2.4% (n=8) respectively. The majority of β-lactamases producing GNB were isolated from urine specimen 47.5% (n=116). Highest resistance level was seen to ampicilline (75.4%), augumentin (64.0%) and sulfamethoxazole-trimethoprim (55.6%). Multidrug resistance (MDR) level was 73.7%. Of β-lactamases producing GNB, 99.3% were MDR (P < 0.05).
Conclusion: The magnitude of β-lactamases producing GNB and MDR were high. Therefore, the emergence of β-lactamases producing GNB requires continuous monitoring & reviewing of antimicrobial policy in hospitals and the country at large. Amikacin, meropenem and imipenem were the most effective antibiotics against β-lactamases producing GNB.
Description
Keywords
Beta-lactamase, Multidrug Resistance, Gram negative bacilli, Extended spectrum β-lactamase, AmpC β-lactamase, Carbapenemase