The impact of asymptomatic kidney stones on disease progression in autosomal dominant polycystic kidney disease.

Background: Autosomal Dominant Polycystic Kidney Disease (ADPKD) is a common hereditary disorder leading to end-stage kidney disease due to the progressive formation of renal cysts. Nephrolithiasis is a frequent complication of ADPKD, with a prevalence significantly higher than in the general population. However, its role in disease progression remains underexplored. This study investigates the impact of asymptomatic nephrolithiasis on kidney function decline in ADPKD patients.

Methods: A retrospective cohort of 195 ADPKD patients was followed at our nephrology clinic. Of these, 85 patients had nephrolithiasis (N+), and 110 did not (N-). Data on demographic characteristics, biochemical parameters, and kidney function were collected. ΔeGFR (change in eGFR over time) served as the primary outcome. Statistical analyses, including correlation and multiple linear regression, were performed to assess the predictors of ΔeGFR.

Results: The N + group exhibited a significantly greater decline in kidney function compared to the N- group (ΔeGFR: 16.53 vs. 12.82 mL/min/1.73 m², p = 0.008). Lower calcium levels were observed in the N + group (p = 0.007), potentially reflecting metabolic abnormalities linked to nephrolithiasis. Nephrolithiasis was independently associated with kidney function decline (B = 3.159, p = 0.038). Follow-up duration was strongly associated with ΔeGFR (p < 0.001). Age showed a trend toward significance but did not reach statistical significance.

Conclusions: Asymptomatic nephrolithiasis is associated with accelerated kidney function decline in ADPKD patients. These findings highlight the importance of monitoring kidney stones, even in the absence of symptoms, to mitigate their impact on renal dysfunction.