Resistance profiles of urinary <i>Escherichia coli</i> and <i>Klebsiella pneumoniae</i> isolates to antibiotics commonly prescribed for treatment of urinary tract infections at Monkole Hospital Center, Kinshasa, Democratic Republic of the Congo

Abstract

Background: The occurrence of urinary tract infection (UTI) caused by multi-drug resistant bacteria is increasing worldwide and has become a major public health concern that requires global attention. To promote better treatment outcome of UTI and raise awareness of antibiotic resistance in the Democratic Republic of the Congo (DRC), we investigated the antimicrobial resistance profile of bacterial pathogens frequently isolated from urine samples of inpatients and outpatients with symptoms of UTI at the Monkole Hospital Center (MHC), Kinshasa from June 2017 to May 2018.

Methodology: This was a retrospective review of results of uro-cultures of urine samples of both inpatients and outpatients who had clinical symptoms of UTI, over a period of one year at the MHC, Kinshasa, DRC. During this period, aerobic uro-cultures of urine were done on MacConkey agar (MAC) or Cystine-Lactose- Electrolyte-Deficient (CLED) agar media at 37oC incubation for 24 hours. Identification of bacterial isolates on the culture media and antimicrobial susceptibility to sixteen selected antibiotics were done using the integral system enterobacteria and the Vitek^® 2 automated system according to the manufacturer’s instructions. The R-studio software was used for statistical analysis.

Results: Of the 2765 uro-cultures performed during the period of study, 809 (29.3%) were positive for bacteria with Escherichia coli being the most frequently isolated bacteria pathogens. There was no significant difference (p>0.05) in the resistance rates of both E. coli and Klebsiella pneumoniae to most of the antibiotics such as amoxicillin-clavulanic acid, piperacillin-tazobactam, amikacin, levofloxacin, norfloxacin, cefuroxime, cefotaxime, cefixime and cephalexin but resistance rates of E. coli compared to K. pneumoniae was significantly higher to cotrimoxazole (OR=2.06, p=0.0016), ofloxacin (OR=3.43, p=0.0019), ciprofloxacin (OR=1.624, p=0.044) and significantly lower to imipenem (OR=0.037, p=0.0046), nitrofurantoin (OR=0.292, p=0.0004) and fosfomycin (OR=0.311, p=0.0003). Both pathogens showed resistance rates of more than 50.0% to doxycycline, cefuroxime, cefixime and cephalexin but resistance rates of K. pneumoniae to ofloxacin and cotrimoxazole was less than 50.0%. The isolates were least resistant to imipenem, piperacillin-tazobactam and amikacin, with less than 13.0% resistance rate.

Conclusion: The findings of this study showed that E. coli is the most isolated bacterial uro-pathogen amongst patients with UTI at MHC Kinshasa, DRC, but both E. coli and K. pneumoniae were resistant to most commonly prescribed antibiotics used for treatment of UTI. Amikacin, piperacillin-tazobactam and imipenem demonstrated high invitro activity and should be prioritized for antimicrobial stewardship to prevent or delay emergence of resistance to them. To guarantee optimal treatment of UTI, regular pathogen surveillance and local antibiogram reporting are required. Further studies are needed in DRC to assess the burden and factors driving antimicrobial resistance nationwide.