LAUSR

INTRODUCTION The global prevalence of lithiasis is 1/7,000, but varies among the different populations. Although cystine lithiasis in pediatrics has an incidence of 2-6%, these patients are more likely to develop new episodes of lithiasis despite receiving adequate treatment. MATERIALS AND METHODS To determine the incidence of cystine renal lithiasis in patients treated at the Puigvert Foundation. To determine the treatment used and its efficacy on these patients. Retrospective descriptive study of the pediatric urology unit of the Puigvert Foundation. Patients from 0 to 18 years old with a diagnosis of cystinuria treated at our institution from 2000-2019 were included. Data were obtained from clinical records. Descriptive statistics and the Chi-square test, contingency tables and Kaplan Meyer's survival curves were used. The value of p<0.05 was considered statistically significant. RESULTS Twenty-eight minimally invasive procedures performed in 9 patients were selected according to the characteristics, location and number of stones. Of these, 15 were combined procedures (RIRS with PNL) due to the complexity of the cases. The mean surgical time was 150minutes. A mean of 3.1 procedures were performed per patient. CONCLUSIONS The incidence of cystine lithiasis is 14% compared to 6% worldwide. Cystine lithiasis in the analyzed population has a difficult management but shows a clear relationship between urinary pH and the number of recurrences in these patients.