Prevalence of Extended‐Spectrum Beta‐Lactamase Producer Gram‐Negative Rods and Associated Factors Among Patients With Wound Infection at University of Gondar Comprehensive Specialized Hospital, Northwest Ethiopia
Authors: Tesfaye Sara , Tafere Wudu , Abebe Wondwossen , Wondimeneh Yitayih 
Published: November 2024

Background: Multidrug‐resistant (MDR) bacteria have significantly affected the management and treatment of wound infections globally. Data on the prevalence of MDR bacterial profiles that cause wound infections in Ethiopia are scarce. Therefore, this study aimed to determine MDR as well as extended‐spectrum beta‐lactamase production profiles of Gram‐negative rods that are difficult to treat with conventional antibiotics and that cause wound infections.

Objective: The aim of the study was to determine the prevalence of extended‐spectrum beta‐lactamase producer Gram‐negative rods and associated factors among patients with wound infection at University of Gondar Comprehensive Specialized Hospital, northwest Ethiopia.

Materials and Methods: This hospital‐based cross‐sectional study was conducted at University of Gondar Comprehensive Specialized Hospital between May and July 2022. Convenience sampling was used to recruit 228 participants. Swabs from different wound types were inoculated onto the MacConkey agar and blood agar plates and incubated overnight at 37°C for 24 h. Biochemical tests were performed on isolated colonies for the identification of bacterial species based on their biochemical reaction. Antimicrobial susceptibility tests were performed using the disk diffusion technique as per the standard Kirby–Bauer method by using Muller–Hinton agar, and the zone of inhibition was interpreted as resistant, intermediate, and sensitive as per the recommendation of Clinical Laboratory Standard Institute. Isolates were tested against ceftriaxone, cefotaxime, and ceftazidime for extended‐spectrum beta‐lactamase screening using the Kirby–Bauer disk diffusion method, and combined disk tests were applied for phenotypic confirmatory test of extended‐spectrum beta‐lactamase producing isolates.

Result: Of 228 study participants, 162 (71.1%) were culture‐positive. Among culture‐positive patients, 165 Gram‐negative bacteria were recovered. The most common Gram‐negative isolates were Pseudomonas aeruginosa (47; 28.5%), followed by Escherichia coli (43; 26.1%) and Klebsiella pneumoniae (24; 14.5%). The susceptibility rates of the isolate for imipenem and tobramycin were 97.0% and 73.2%, respectively, and the overall multidrug resistance rate was 80.5%. Extended‐spectrum beta‐lactamase producer bacteria were also isolated. Besides, all (100%) of extended‐spectrum beta‐lactamase producer bacteria were MDR. Living in rural areas (AOR 5.8; 95% CI [2.01–16.7]), hospital admission (AOR 3.95; 95% CI [1.13–13.83]), antibiotic use (AOR 2.83; 95% CI [1.03–7.72]), and comorbidity (AOR 0.25; 95% CI [0.07–0.59]) were significantly associated with wound infection.

Conclusions and Recommendations: There was a high prevalence of Gram‐negative bacterial isolates in this study. Pseudomonas aeruginosa (28.5%) was the predominant isolate. In addition, high rates of multidrug resistance were observed. The high level of multidrug resistance in this study implies that definitive therapy should be based on culture and susceptibility analysis to promote the rational use of antibiotics and to reduce the emergence of bacterial resistance to antimicrobials.