Öz

Objective: Cystinosis remains a significant cause of morbidity in developing countries. Key challenges include limited access to specialized clinics, availability of cysteamine treatment, and difficulties in monitoring treatment efficacy, such as measuring leukocyte cystine levels. The aim of this study was to describe the clinical characteristics, growth patterns, and renal outcomes of pediatric patients with nephropathic cystinosis in a resource-limited region

Material and Methods: This retrospective study included 17 patients diagnosed with cystinosis who were followed in the Pediatric Nephrology Clinic of a tertiary care center between June 2016 and April 2023. Clinical and laboratory characteristics were evaluated, and statistical analyses were performed using IBM SPSS Statistics.

Results: After a median follow-up period of 69.24 months, no significant change was observed in weight SDS ((median [IQR]; baseline vs. follow-up; -3.6 [1.35] vs. -2.8 [1.55], p=0.255). However, height SDS significantly decreased (median [IQR]; baseline vs. follow-up; -2.8 [2.44] vs. -3.9 [2.35], p=0.034). Ocular involvement was present in all patients, and six were diagnosed with hypothyroidism. The majority of patients (n=9) exhibited biochemical features consistent with renal Fanconi syndrome. One patient initially presented with persistent hypochloremic hypokalemic metabolic alkalosis and subsequently developed Fanconi syndrome during follow-up, while another showed transient metabolic alkalosis at presentation. The median estimated glomerular filtration rate (eGFR) significantly declined from diagnosis (116.66 [62.69] mL/min/1.73 m²) to the last follow-up (77.40 [95.18] mL/min/1.73 m², p=0.007). Twelve patients had an eGFR <90 mL/min/1.73 m²; three progressed to stage 3 chronic kidney disease, and three required renal replacement therapy.

Conclusion: Growth retardation and progression to chronic kidney disease are significant challenges for cystinosis patients in resource-limited settings. Improving access to specialized care and monitoring is essential to enhance patient outcomes.

Anahtar Kelimeler: Cystinosis, chronic kidney disease, cysteamine, nephropathic cystinosis

Kaynakça

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Nasıl atıf yapılır

1.
Köksoy AY, Görükmez O. Clinical and laboratory characteristics of nephropathic cystinosis in a resource-limited region. Turk J Pediatr Dis. 2026;Early View:1-6. https://doi.org/10.12956/TJPD.2025.1256