Particularities of Pyelonephritis With Multidrug-Resistant (MDR) Germs During Pregnancy: A Case-Control Study

Introduction: The aim of this study was to analyze the characteristics of pyelonephritis with multidrug-resistant (MDR) bacteria in pregnant women in comparison to pyelonephritis with multidrug-sensitive bacteria in this particular patient group.

Methods: We conducted a retrospective study over a period of three years on a study group of 17 pregnant patients with pyelonephritis with MDR bacteria and on a control group of 52 pregnant patients with pyelonephritis with multidrug-sensitive bacteria. We analyzed the demographic data, the potential risk factors, aspects of the clinical picture, the incidence and type of bacteria involved, and their sensitivity spectrum.

Results: The patients in the study group had pyelonephritis on the right side (N=10, 58.83%), were in the second and third trimesters of pregnancy (N=16, 94.12%), and had a high percentage of anemia (N=9, 52.94%), as did the control group. Unlike the patients in the control group, the patients in the study group had a higher incidence of antibiotic treatment (N=17,100% vs. N=14, 29.92%, p<0.001), previous urological surgery, especially ureteral catheterization with insertion of double-J catheters (N=9, 52.94% vs. N=9, 17.30%, p=0.003), and an increased incidence of urosepsis on admission (N=11, 64.70% vs. N=11, 21.15%, p<0.001). E. coli (N=8, 47.05% vs. N=28, 53.85%, p=0.626) and Klebsiella pn. (N=5, 29.41% vs. N=12, 23.07%, p=0.598) were predominant in both study groups. Also, the hospitalization days were significantly higher in the study group compared with the control group (N=7.38±2,91 vs. N=5.02±1,87, p=0.002). The spectrum of microbial resistance was increased in favor of the study group for all antibiotics tested, with the exception of ampicillin, where resistance was increased in both groups. The Gram-negative bacteria responsible for the pyelonephritis in both groups retained 100% sensitivity to carbapenems and piperacillin/tazobactam.

Conclusions: Pregnant women in the second and third trimesters of pregnancy who have undergone right-sided double-J catheter insertion during pregnancy and/or who have received antibiotic treatment in the past are at increased risk for pyelonephritis with MDR. E. coli and Klebsiella pn., bacteria are most commonly involved and maintain susceptibility to carbapenems and reserve penicillins.