Urinary tract infection in critically ill patients with diabetes mellitus: Spectrum of uropathogens and antimicrobial susceptibility pattern

Background: Urinary tract infections (UTIs) are common and more severe among patients with diabetes mellitus (DM). UTI in DM is more likely to be caused by bacteria resistant to various antimicrobials. The present study aims to assess the spectrum of bacteria causing UTI and its antimicrobial susceptibility pattern among critically ill patients with DM. Materials and Methods: The present study included 272 patients with DM and UTI, age more than 18 years, admitted in the intensive care unit of a tertiary care hospital in the state of Uttarakhand, India. The pathogens causing UTI were isolated, identified and antimicrobial susceptibility testing was performed using automated VITEK method as described by the Clinical and Laboratory Standards Institute. Results: UTI was caused by Gram-negative bacteria of Enterobacteriaceae family in 89.7% and by Gram-positive bacteria in 10.3% of the study participants. Escherichia coli was the most common Gram-negative bacteria causing UTI followed by Klebsiella pneumoniae and Proteus spp. Enterococcus faecalis was most common Gram-positive isolate. Gram-negative bacteria were highly susceptible to colistin, fosfomycin, carbapenems, and aminoglycosides. Carbapenem resistance was observed in 16.4% of these isolates. Gram-positive bacteria were most susceptible to vancomycin, teicoplanin, linezolid, and fosfomycin. Conclusion: Gram-negative bacteria, particularly E. coli were the most common uropathogens causing UTI in critically ill patients with DM. These bacteria showed good antimicrobial susceptibility to colistin, fosfomycin, carbapenems, and aminoglycosides. Carbapenem-resistance was found in one-sixth of the Enterobacteriaceae isolates. Gram-positive bacteria caused UTI in about 10% of the study participants and were susceptible to vancomycin, teicoplanin, and linezolid.