Abstract

Introduction:
Cystinuria is a rare genetic disorder. Many patients suffer from significant recurrent urolithiasis, repeated surgical interventions and the risk of progressive renal impairment. In the current study, the outcomes of patients with cystine stones were investigated.

Methods:
A total of Twenty-six cystinuria patients with cystine stones, aged between 3 months and 18 years, in our Pediatric Nephrology Department, were retrospectively analyzed.

Results:
The mean age of patients at diagnosis was 45.2±45.5 months and 88,5% were male. Sixteen (62%) children had recurrent urinary tract infections. Only 10 (38%) patients revealed additional metabolic abnormalities. The urinary pH had significantly increased with treatment and the number of stone recurrence was lower in the patients with urinary pHs ≥ 6.5. There was a significant positive correlation between the last-visit serum creatinine level and the number of surgical interventions. There was not a significant correlation between the last-visit eGFR and the number of surgical interventions, on the other hand, eGFR values decreases as the total number of surgical interventions increases. No stone events were observed at the end of the follow-up period in 10 patients (38%) and the stone events per patient-year was 0.36 for all patients. Four patients with low eGFRs at the beginning of the study get normal with treatment after the follow-up period.

Conclusion:
Cystinuria has significant morbidity if not properly controlled. Despite all treatments, it should be kept in mind that renal impairment may develop in cystinuria and surgical treatment should be planned by considering minimally invasive options.

Keywords: child, cystinuria, Urolithiasis, Kidney stones

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Copyright © 2022 The Author(s). This is an open access article distributed under the Creative Commons Attribution License (CC BY), which permits unrestricted use, distribution, and reproduction in any medium or format, provided the original work is properly cited.

How to cite

1.
Çaycı Ş, Acar B, Tiryaki T, Bayrakçı US. Evaluation of Children with Cystine Stones: A single-Center Experience. Turk J Pediatr Dis [Internet]. 2022 Jan. 28 [cited 2025 Aug. 23];16(1):5-10. Available from: https://turkjpediatrdis.org/article/view/911