Retrospective Assessment of Antimicrobial Susceptibility Patterns of Bacteria Isolated from Priority Specimens at the Tertiary Hospital in Tanzania
Kauke B Zimbwe, Charity A Chiwambo, Yusto J Yona, Moshi M Shabani, Alphonce B Chandika, Humphrey S Kiwelu, Omary S Kizenga, Rueben S Mkala, Catharine Masalu, Henry Joseph, Witness M MchwampakaAbstract
Background
Antimicrobial resistance (AMR) has dramatically increased in hospitals and communities, posing challenges in treating infectious diseases caused by bacteria. Our study aimed to develop three years of antimicrobial susceptibility trends by assessing the AMR pattern of bacteria in blood, urine, and wound swabs.
Method
A single-centre retrospective cross-sectional study was conducted at The Benjamin Mkapa Tertiary Hospital in Dodoma, Tanzania. Electronic medical records and laboratory results of patients from January to December 2020 to 2022 were reviewed. The study aimed to analyse the trends in antimicrobial susceptibility of urine, wound/pus swabs, and blood samples.
Results
The number of positive blood samples tested for antimicrobial susceptibilities were 166, 191, and 247 in 2020, 2021, and 2022, respectively. Escherichia coli showed susceptibility to carbapenems, aminoglycosides, amikacin, and piperacillin-tazobactam with an increased resistance of 80% to third-generation cephalosporins. Staphylococcus aureus displayed a decrease in susceptibility trends for ciprofloxacin and levofloxacin, while gentamycin, vancomycin, clindamycin, and azithromycin showed susceptibilities of over 60%. The antimicrobial susceptibilities of 65 positive wound/pus swabs were assessed in 2020, 197 in 2021, and 326 in 2022. Over the years, Pseudomonas aeruginosa exhibited varying susceptibility to ciprofloxacin, carbapenems, and piperacillin-tazobactam. Acinetobacter baumannii isolates showed susceptibility to sulfamethoxazole-trimethoprim (>60%), ciprofloxacin (>60%), imipenem (>70%), gentamycin (>65%), and amikacin (>80%) in 2020-2022. Additionally, the number of positive urine samples tested for antimicrobial susceptibilities was 107 in 2020, 306 in 2021, and 407 in 2022. Escherichia coli and Klebsiella pneumoniae were susceptible to several antibiotics with over 70% susceptibility.
Conclusion
Our study has revealed increased antimicrobial resistance (AMR) proportions across various bacteria found in urine, pus, and blood samples. We also found multidrug resistance (MDR) in gram-negative and gram-positive pathogens. To address the limitations identified in the study, we recommend implementing comprehensive prospective single-centered active AMR surveillance.