Characterization of Nephrolithiasis in ADPKD

Background: Nephrolithiasis (NL) occurs in a significant proportion of patients with autosomal dominant polycystic kidney disease (ADPKD). However, the true prevalence and incidence of NL in ADPKD remain poorly understood, limiting our ability to appreciate the contribution of NL to the course of ADPKD. Here we characterized the patterns of NL and its relation to kidney disease progression in a previously unstudied multi-ethnic cohort of patients with ADPKD. Methods: A single-center retrospective study was performed on 235 patients from the PKD Clinic at The University of Texas Southwestern Medical Center. Included were patients diagnosed with ADPKD based on imaging, family history and/or genetic testing, who were seen at least twice in clinic, with their last visit occurring between 1/1/2020 and 3/31/2025. Clinical history, laboratory values, and imaging studies were analyzed. Results: At the initial visit, the prevalence of nephrolithiasis was 32%. 73% of stone formers were symptomatic with either flank pain or hematuria. Stones were mainly composed of calcium oxalate or uric acid. Hypocitraturia was the most common urinary abnormality among stone formers, seen in 54% of patients who completed a 24-hour urine collection. There was no significant difference between stone and non-stone formers in terms of sex, race, Mayo Imaging Classification, or family history of NL (Table). The median eGFR decline was 2.7 ml/min/1.73m2 per year and comparable between stone and non-stone formers. Over a mean of 2.4 years of follow-up, the incidence of NL was 1.83 cases per 100 patient/year. Conclusion: We have described the incidence and prevalence of nephrolithiasis in a previously unstudied population of patients with ADPKD. Long term studies with a larger sample size will be required to discern any correlation between NL, ADPKD severity, and rate of eGFR decline.