Background: Urinary tract infections (UTI) are one of the important clinical presentations in patients with autosomal dominant polycystic kidney disease (ADPKD). The association between UTI among genotypic and phonotypic properties of ADPKD patients is still obscure. Thus, we investigated the relationship between UTI and polycystin gene mutation with total kidney volume.
Methods: Forty patients with ADPKD patients with a history of more than two UTI and age-gender-matched 40 ADPKD patients without UTI history enrolled in the study. Ambulatory blood pressure monitoring was performed in all participants. Magnetic resonance imaging (MRI) was performed with a 1.5-T system, and total kidney volumes were calculated using mid-slice technique. To determine PKD1 and PKD2 genotype, we performed molecular and genetic tests involving the following steps: DNA isolation, next-generation sequencing (NGS) and data analysis.
Results: ADPKD patients with UTI had lower eGFR values than those without UTI [64.9 (32.2-100.8) vs 89.5 (59.0-110.0) (p = 0.041)]. In addition, patients with UTI had significantly increased height-adjusted total kidney volume than patients without UTI [950 (290-1350) vs 345 (243-780.0) (p = 0.005)]. Multiple logistic regression analysis showed that the PKD1-truncating mutation and hTKV independently predicted UTI. The sensitivity and specificity of hTKV were 65% and 77% (cutoff > 727 cm3) with an area of under the ROC curve of 0.70 (95% CI 0.56-0.85, p = 005).
Conclusions: ADPKD patients with larger kidneys and PKD1 mutation are susceptible to increased risk of multiple UTI. Additionally, renal function decreased in ADPKD patients with multiple UTI history.
Keywords: Polycystic kidney disease; Total kidney volume; Urinary tract infection.