Presentation Authors: Shu Wang*, Baltimore, MD, Yitian Zhang, Chapel Hill, NC, Xin Zhang, Jianxing Li, Beijing, China, People's Republic of
Introduction: MDR bacteria can lead to intractable infection in patients with urolithiasis and increase mortality rate as well as medical costs. Thus it is important for clinicians to establish evidence-based strategies of antibiotics use. This study aims to evaluate the prevalence of MDR bacteria in a high volume stone management center and investigate the resistance patterns.
Methods: A retrospective study was performed among patients diagnosed with urolithiasis in Beijing Tsinghua Changgung Hospital from 2014 December to 2018 May. Only patients who had positive urinary culture with a bacteria growth >10^5 colony-forming units and drug-sensitivity tests were included. MDR bacteria were defined as any bacteria that gain resistance to at least one agent in >/=3 classes of antibiotics.
Results: 1655 patients with urolithiasis were analyzed, among which 357 patients had positive urinary culture results, yielding 457 isolates of 45 kinds. The E.coli remains the most common with a prevalence of 29.3%, followed by E.faecalis (12.0%), P.mirabilis (10.5%), K.pneumonia (6.8%),and S.agalactiae (4.8%). 44.4% isolates were identified as MDR. The most 3 common G- bacteria were E.coli, P.mirabilis, and K.pneumonia, with a MDR rate of 84.33%, 62.5%, and 48.39%, respectively. The most 3 common G+ bacteria were E.faecalis, S.agalactiae, and E.faecium, with a MDR rate of 0, 54.55%, and 0, respectively. As for the most 3 common G- bacteria, drug-resistance rates were different between MDR and non-MDR in Ampicillin, Ampicillin/sulbactam, Cefozolin, Ceftriaxone, Ceftazidime, Cefepime, Gentamicin, Amikacin, Ciprofloxacin, and Levofloxacin, while there were no significant differences among the drug-resistance rates in Piperacillin/tazobactam, Cefperazone/Sulbactam, and Carbapenems. Antibiotics combined with beta-lactamase inhibitors achieved lower drug-resistance rates in both MDR and non-MDR group(p < 0.001).
Conclusions: MDR bacteria were common among patients with urolithiasis, achieving high drug-resistance rates of Ampicillin, first-generation and part of third-generation cephalosporins, and fluoroquinolones. Antibiotics with beta-lactamase inhibitors, carbapenems, and amikacin proved to be effective for MDR bacteria.