Gene characterization of extended-spectrum-β-lactamase producing Klebsiella pneumoniae isolates and analysis of interleukin-11 in patients with urinary tract infection

Abstract

Cross-sectional and case-control study was conducted on 587 patients with urinary tract infection (UTI) to determine prevalence of Klebsiella pneumoniae and three extended-spectrum-β-lactamase (ESBL) genes (blaSHV, blaTEM and blaCTX-M). Besides, IL-11 serum level was determined to predict its biomarker significance in patients with ESBL-producing K. pneumoniae (K-ESBLs). Ninety-three K. pneumoniae isolates were identified (15.8%), and 64 (68.8%) of these isolates were K-ESBLs, which showed a high prevalence of resistance against 12 antibiotics out of 16. PCR analysis of K-ESBLs revealed that blaSHV gene was prevalent in all isolates (100.0%), while blaTEM gene was detected in 35 isolates (54.7%). blaCTX-M gene was found in only two isolates (3.1%). IL-11 levels were significantly elevated in K-ESBL and K-non-ESBL patients compared to controls (52.4 ± 21.8 and 34.5 ± 18.8 vs. 6.3 ± 4.2 pg/mL, respectively; p-value <0.001), but it is noteworthy that IL-11 levels were significantly higher in K-ESBL patients than in non-ESBL patients (p-value <0.001) (Fig. 1). ROC curve analysis revealed that IL-11 was a significant predictor of K-ESBLs in patients with UTI. This cytokine occupied an excellent AUC, which was 1.0. At a cut-off value of 11.1 pg/mL, the sensitivity and specificity of IL-11 were 100.0%. In conclusion, the study demonstrated the significance of K-ESBLs in the development of UTIs, and this uropathogen showed a high level of multidrug resistance, as well as a high frequency of blaSHV and blaTEM genes. Besides, IL-11 may have emerged as a significant indicator of UTIs caused by K-ESBLs.