Dissolution of uric acid stones and factors associated with treatment success: EAU endourology systematic review and meta-analysis

Objective and Background Citrate-based urinary alkalization is recommended as first-line pharmacological therapy for uric acid stone dissolution. Reported effectiveness varies across studies, and guideline estimates are largely derived from heterogeneous cohorts . This systematic review and meta-analysis aimed to quantify the effectiveness of citrate-based therapy using intention-to-treat populations and to identify factors associated with successful stone dissolution.Methods and Materials A systematic literature search was performed, and eligible studies evaluating citrate-based therapy for uric acid or radiolucent urinary stones in adults were included. The review was prospectively registered in PROSPERO (CRD420261280790). Subgroup and patient-level analyses were performed to explore sources of heterogeneity. Patient-level comparisons between responders and non-responders were synthesized where available. Risk of bias and certainty of evidence were assessed using validated tools.Results Six studies comprising 618 patients met inclusion criteria. The pooled rate of complete or partial stone dissolution was 64% (95% CI 40–83%), but heterogeneity was substantial (I2 = 90%) and the prediction interval was wide (14–95%) . Treatment failure or surgical intervention occurred in 21% of patients, and treatment discontinuation due to adverse events or low compliance occurred in 18%. Reported effectiveness varied significantly by outcome definition and urine pH targets. Higher dissolution rates were reported in studies targeting a urine pH of 6.2–6.49. Patient-level analyses identified higher urine pH during therapy and lower stone density as the factors most consistently associated with treatment response.Conclusion The effectiveness of citrate-based dissolution therapy for uric acid stones appears lower than commonly cited in clinical guidelines, although the pooled estimate is highly heterogeneous . Optimal urine pH targeting, standardized imaging, and consistent outcome definitions appeared to be important factors associated with successful chemolysis in the available literature.