Alternative Antimicrobials for Treating Infections Caused by Drug-Resistant Uropathogens: An In vitro Laboratory-Based and Analytical Interpretation

To determine the overall in vitro resistant rates among common uropathogens in order to indicate alternative antimicrobials for consideration in the future treatment of urinary tract infection (UTI).

Data included in this study were derived from 4 years (2013–2016) cross-sectional, a retrospective study carried out in Aseer Central Hospital, Saudi Arabia. Culture positives urine and other UT specimens (n=47193) obtained from patients suspected of having UTIs were identified and tested for antimicrobial assay using the VITEK 2 system. The analysis was done using SPSS software on culture positive samples against 39 antimicrobial agents and combinations of more than one agent.

Of the 47193 culture positive uropathogens, 51.5% were resistant to the 39 agents, whereas 48.5% were sensitive (p=0.7969). Antimicrobials with high sensitivity to all uropathogens were linezolid (99.1%), daptomycin (98.3%), vancomycin (86.7%), ertapenem (86.3%), teicoplanin (85.5%), tigecycline (85.3%), imipenem (82.4%), meropenem (79.6%), piperacillin/tazobactam (78.6%), and colistin (76.2%). In contrast, antimicrobials with high resistance were cephalothin (91.0%), nalidixic acid (86.7%), cefuroxime (79.6%), cefazolin (76.3%), mezlocillin (76.1%), piperacillin (73.6%), ceftriaxone (72.9%), norfloxacin (72.8%), ciprofloxacin (71.7%), and cefotaxime (69.7%).

Empirically prescribed antimicrobials have displayed remarkable resistance in this survey. Information on the local antimicrobial trends is needed to plan evidence-based recommendations. Drugs such as linezolid, daptomycin, vancomycin, ertapenem, teicoplanin and tigecycline indicated good alternatives (≥ 85% sensitivity) for consideration in empirical UTI therapy. However, cephalothin, nalidixic acid, and cefuroxime revealed high resistance rates (≥ 80%).