Background: To date, estimates of cystinuria’s burden of disease and its implications have been absent in the literature. Cystinuria is an autosomal recessive, rare source of nephrolithiasis that can lead to aggressive and recurrent kidney stones, characterized by impaired transport of cystine. Published data has been largely limited to single institution and small multi-institutional case series. Demographics are not well defined and clinical applicability on a national scale is lacking. We leveraged a large collaborative network to develop the largest cystinuric cohort to date and provide insights into epidemiology and management.
Methods:We used the TriNetX, LLC Global Collaborative Network which drew from deidentified electronic medical records of over 143 million patients from 117 health care organizations across 17 countries in North and South America, Europe, Africa, and Asia, including academic medical centers, insurance providers, and private practice groups between 2004-2023. Demographics, diagnosed comorbidities, prescribed medications, laboratory values, and procedures were queried. This study was exempted from International Review Board approval as it only used deidentified patient information.
Results:Of 143 million patients, 2.48 million had stones and 2,049 had stones and an ICD diagnosis of cystinuria. The cohort had a mean age of 50 (age range 1-90). 49.64% were male, 71.8% were white, and 8.14% were black. Life-time prevalence of moderate to severe CKD (stage III-V) was 30%. 39% had required ureteroscopy at any time point and 21% had required PCNL. 22% had been prescribed tiopronin, and 42% had been prescribed potassium citrate.
Conclusions:While cystinuria may be a rare cause of nephrolithiasis in the general community, our data provide improved understanding of the burden of the disease on a global scale. Moderate to severe CKD affects 30%, and surgical interventions are often required. Almost half of patients receive urinary alkalinization, but less than a quarter receive tiopronin. Such data from a multi-center data network provides an overview of the largest cohort of cystinurics to date and may help inform future targets to improve quality of care.
