Risk stratification for repeat stone surgery: the role of stone composition.

Abstract

Purpose: Kidney stones have a recurrence risk of 30-50% within five years, with surgical recurrence often being the most clinically significant and burdensome. Stone composition results obtained after surgery are readily available and typically precede metabolic evaluation. However, only few, relatively small studies, correlated stone composition with surgical reccurence. This study aims to determine whether stone composition alone can reliably predict recurrent stone surgery, offering insights into personalized management strategies.

Methods: A retrospective analysis of surgically treated patients with an available stone composition analysis performed between 2013 and 2020 in a large healthcare provider database. Data were analyzed for up to 5 years from the initial surgery.

Results: 8,561 patients underwent surgical procedures for stones and 2,097 (24.5%) had repeat surgery within 5 years. Compared to calcium oxalate stone formers, individuals forming uric acid, calcium phosphate, infection, brushite, and cystine stones were 1.5, 1.5, 1.87, 2.64, and 2.71 times more likely, respectively, to undergo a second stone surgery (p < 0.001). The median time for repeat stone surgery in cystine and infection stone formers was significantly shorter compared to calcium oxalate (p < 0.01).

Conclusions: Stone composition significantly affects the 5-year surgical recurrence rates and the median time to recurrence, with non-calcium oxalate stone formers at a higher risk for recurrence. Sharing this information with patients may improve compliance with preventive strategies, including comprehensive metabolic evaluation and adherence to preventive therapy. Emphasizing this risk may help prioritize proactive management in high-risk patients.