Prevalence and antimicrobial susceptibility of multi drug-resistant bacteria isolates in adult intensive care units: a six-year retrospective study from a tertiary hospital in Mogadishu, Somalia.

BACKGROUND

This study aimed to determine the prevalence, distribution, and antimicrobial susceptibility patterns of multidrug-resistant (MDR) bacterial isolates in adult intensive care units (ICUs) at a tertiary care hospital in Mogadishu, Somalia.

METHODS

A retrospective study was conducted from January 2019 to August 2024. Blood, urine, and deep tracheal aspirate samples were collected from ICU patients aged ≥ 18 years. Microorganisms were identified using conventional methods at our hospital. Isolates were categorized as Gram-negative (GN), Gram-positive (GP), and Candida species. Subgroup Candida was not identified. Antimicrobial susceptibility testing was performed and interpreted according to Clinical and Laboratory Standards Institute (CLSI) guidelines using disk diffusion and E-test methods. Bacterial strains were classified according to their antibiotic resistance as MDR, possible extensively drug-resistant (XDR), or possible pandrug-resistant (PDR). Temporal trends in microbial distribution and resistance patterns were analyzed and compared with regional and global data.

RESULTS

Of 2,185 isolates, 75.1% were GN bacteria, 18.9% GP bacteria, and 6% Candida species. Among bacterial isolates, 53.6% (n = 1,100) were MDR, with MDR rates of 52.3% in GN and 58.5% in GP bacteria. Most GN-MDR isolates belonged to the possible XDR category, with high carbapenem resistance rates, particularly in Klebsiella [2.8% (n = 16) K. oxytoca, 28.8% (n = 163) K. pneumoniae, and 68.4% (n = 387) Klebsiella spp.] and Acinetobacter [56.8% (n = 133) A. baumannii and 43.2% (n = 101) Acinetobacter spp.]. A marked increase in MDR prevalence and resistance rates was observed from 2022 onward. By 2024, Candida species became the second most common cause of bloodstream infections, surpassing GP bacteria. Colistin and tigecycline showed the highest efficacy against GN-MDR strains, while vancomycin, linezolid, daptomycin, and quinupristin-dalfopristin were most effective against GP-MDR isolates.

CONCLUSION

The high prevalence of carbapenem-resistant Klebsiella and Acinetobacter in our ICUs exceeds global averages and underscores the urgent need for antimicrobial stewardship and robust infection control measures in Somalia. Although treatment options for GP-MDR bacteria are relatively more effective, management of GN-MDR infections remains limited and challenging.