# Association Between Stone Composition and Recurrence Rates Following Ureteroscopy: A Scoping Review

## TL;DR

This review examines how different types of kidney stones affect recurrence rates after ureteroscopy, finding that calcium-based stones are linked to higher recurrence.

## Contribution

The study identifies gaps in evidence regarding stone composition and recurrence, emphasizing the need for standardized research methods.

## Key findings

- Calcium oxalate stones are associated with higher recurrence rates after ureteroscopy.
- Recurrence rates varied widely, from 25.8% at 32 months to nearly 60% at 36 months.
- Inconsistent reporting of uric acid, struvite, and cystine stones limits definitive conclusions.

## Abstract

Urolithiasis remains a significant global health burden, with high recurrence rates following intervention. Ureteroscopy is increasingly preferred due to its safety and efficacy; however, recurrence after ureteroscopy is common and may be influenced by stone composition. This scoping review aims to explore the relationship between stone composition and recurrence rates post-ureteroscopy and to identify gaps in current evidence that could inform clinical practice and research. Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews guidelines, we conducted a structured literature search (2014-2024) across PubMed, Scopus, MEDLINE, and Google Scholar. Studies were eligible if they reported on adult patients (≥18 years) undergoing ureteroscopy for renal or ureteric stones, provided stone composition data, and reported recurrence (defined radiologically, symptomatically, or via reintervention). Retrospective/prospective cohort studies, clinical trials, and case series (n >10) in English were included. Non-English, paediatric-only studies, case reports, and those lacking recurrence or composition data were excluded. In total, 13 studies met the inclusion criteria. Calcium oxalate was the most frequently reported stone type and appeared to be associated with higher recurrence rates. Reported recurrence ranged from 25.8% at 32 months to nearly 60% at 36 months, particularly in patients without metabolic follow-up. Reporting of uric acid, struvite, and cystine stones was inconsistent, limiting firm conclusions. The majority of studies were retrospective, small-scale, and lacked standardised definitions of recurrence, often conflating residual fragments with true recurrence. Language restriction and lack of granular metabolic data further limited synthesis. Stone composition appears to influence recurrence risk post-ureteroscopy, particularly for calcium-based stones. However, variability in study design, recurrence definitions, and underreporting of metabolic data reduce the strength of current evidence. Future prospective research with standardised reporting and broader linguistic inclusion is essential.