Multidrug-resistant profile and prevalence of extended spectrum β-lactamase and carbapenemase production in fermentative Gram-negative bacilli recovered from patients and specimens referred to National Reference Laboratory, Addis Ababa, Ethiopia

Abstract

Background: The emergence of multidrug-resistance (MDR), production of extended-spectrum β-lactamases, and carbapenemase in members of fermentative gram-negative bacilli are a serious threat to public health.

Objective: The aim of this study was to determine the burden of multi-drug resistance, the production of extended-spectrum β-lactamases (ESBLs), and carbapenemase in fermentative Gram-negative bacilli in Ethiopian Public Health Institute.

Materials and methods: A cross-sectional study was carried out from December 2017 to June 2018. Different clinical samples were collected, inoculated, and incubated according to standard protocols related to each sample. Bacterial identification was performed by using the VITEKR 2 compact system using the GNR card. Antimicrobial susceptibility testing was carried out by the Kirby-Bauer disc diffusion method. Production of ESBL and carbapenemase were confirmed by combination disc and modified Hodge Test method respectively.

Results: A total of 238 fermentative Gram-negative bacilli were recovered during the study period, among which E.coli were the predominant isolates followed by K. pneumoniae. The highest percentage of antibiotic resistance was noted against ampicillin (100%) followed by trimethoprim/sulfamethoxazole (81.9%). The isolates showed better sensitivity towards carbapenem drugs. Out of 238 isolates, 94.5% were MDR and of which 8.8% and 0.8% were extensively and pan drug resistant, respectively. Nearly 67% and 2% of isolates were producers of ESBL and carbapenemase, respectively. The isolation rates of MDR, ESBL, and carbapenemase producing stains of the isolates were ≥70% in intensive care unit while the isolation rates in other wards were ≤25%.

Conclusions: The findings of this study revealed that the burden of MDR and ESBL was high and carbapenemase producing isolates were also identified which is concerning. This situation warrants a consistent surveillance of antimicrobial resistance of fermentative Gram-negative bacilli and implementation of an efficient infection control program.

Fig 1. Prevalence of MDR, ESBL, and carbapenemase producing in FGNB among different wards.

Fig 2. Prevalence of MDR, ESBL and carbapenamese producing FGNB among different clinical specimens.

Fig 3. Prevalence of MDR, ESBL and carbapenamese producing FGNB between antibiotic exposed and non-exposed patients.