ABSTRACT
Background: Clinicians rely on local antimicrobial resistance pattern data to guide empiric treatment for seriously ill patients when culture and antimicrobial susceptibility testing results are not immediately available. Objective: This study aimed to analyse 5-year trends in antimicrobial resistance profiles of Escherichia coli and Klebsiella pneumoniae isolates. Methods: Bacteriology reports from 2017 to 2021 at the Ethiopian Public Health Institute were analysed retrospectively. Isolates were identified using either the VITEK 2 Compact system, the BD Phoenix M50 instrument, or conventional biochemical tests. Antimicrobial susceptibility testing was conducted using either the Kirby-Bauer disk diffusion method or the VITEK 2 Compact system and BD Phoenix M50 systems available at the time of testing. The Cochran Armitage trend test was employed to test the significance of antimicrobial resistance trends over time. P-values less than 0.05 were considered statistically significant. Results: Of the 5382 bacteriology reports examined, 458 (9%) were on E. coli and 266 (5%) were on K. pneumoniae. Both K. pneumoniae (88%) and E. coli (65%) demonstrated high resistance to extended-spectrum cephalosporins. However, both K. pneumoniae (14%) and E. coli (5%) showed lower rates of resistance to carbapenems compared to other antimicrobials. In K. pneumoniae, resistance to carbapenems (from 0% to 38%; p < 0.001) and ciprofloxacin (from 41% to 90%; p < 0.001) increased significantly between 2017 and 2021. Conclusion: Both organisms showed very high resistance to broad-spectrum antibiotics. Additionally, K. pneumoniae demonstrated a statistically significant rise in ciprofloxacin and carbapenem resistance. What this study adds: This study emphasises the significance of regular reporting of local antimicrobial resistance patterns as this information can guide appropriate empiric therapy and efforts to address antimicrobial resistance issues.
ABSTRACT
Staphylococcus aureus is among the top three causative agents of nosocomial infection in Ethiopia. The majority of studies in Ethiopia have focused on the epidemiology of S. aureus in hospital settings, with limited molecular genotyping results. Molecular characterization of S. aureus is essential for identification of strains, and contributes to the control and prevention of S. aureus infection. The aim of the current study was to determine the molecular epidemiology of methicillin-susceptible S. aureus (MSSA) and methicillin-resistant S. aureus (MRSA) isolates recovered from clinical specimens in Ethiopia. A total of 161 MSSA and 9 MRSA isolates were characterized using pulsed-field gel electrophoresis (PFGE) and staphylococcal protein A (spa) typing. Based on the PFGE analysis, MSSA isolates were grouped into eight pulso-types groups (from A to I), while MRSA isolates clustered into three (A, B and C) pulso-types with more than 80% similarity. The spa typing analysis showed diversity of S. aureus with 56 distinct spa types. Spa type t355 was most prevalent (56/170, 32.9%), while eleven new spa types were detected including t20038, t20039, and t20042. The identified spa types were clustered into 15 spa-clonal complexes (spa-CCs) using BURP analysis; novel/unknown spa types were further subjected to MLST analysis. The majority of isolates belonged to spa-CC 152 (62/170, 36.4%), followed by spa-CC 121 (19/170, 11.2%), and spa-CC 005 (18 /170, 10.6%). Of the nine MRSA isolates, 2 (22.2%) were spa-CC 239 with staphylococcal cassette chromosome (SCC)mec III. These findings highlight the diversity of S. aureus strains in Ethiopia, as well as the presence of potentially epidemic strains circulating in the country necessitating further characterization of S. aureus for antimicrobial resistance detection and infection prevention purposes.
