ESPN 51th Annual Meeting

ESPN 2018


 
Clinic and genetic presentation of children with cystinuria
CAGRI OZCELIK 1 ALI ANARAT 1 NESLIHAN ONENLI MUNGAN 3 ATIL BISGIN 2 BAHRIYE ATMIS 1 ENGIN MELEK 1 AYSUN KARABAY BAYAZIT 1

1- CUKUROVA UNIVERSITY, FACULTY OF MEDICINE, DEPARTMENT OF PEDIATRIC NEPHROLOGY
2- CUKUROVA UNIVERSITY, DEPARTMENT OF MEDICAL GENETIC
3- CUKUROVA UNIVERSITY, FACULTY OF MEDICINE, DEPARTMENT OF PEDIATRIC METABOLISM
 
Introduction:

Cystinuria is an inherited disorder of cystine and dibasic amino acid transport system in the proximal tubule. We aimed to determine the genetic diversity in patients with cystinuria which starting in the childhood age, evaluate the effect of the genetics in clinic, and determine the relationship between the genetic structures of the patients and prognosis of the disease. 

Material and methods:

The study was conducted in the Cukurova University, Department of Pediatric Nephrology in between February 2017 and February 2018. Sixty-two patients who had been diagnosed with cystinuria between 2000-2018, were examined retrospectively and their characteristic data were analyzed. Blood and urine samples were collected from thirty-one patients with cystinuria. Genetic analysis were done through two gene sequence analysis and sanger sequencing method. 

Results:

Fifteen of 31 patients had proven mutations in SLC3A1 and SLC7A9. Polymorphism in SLC3A1 and SLC7A9 were detected in 16 of patients (51.6%). No new mutation was detected in any of the patients. No statistically significant differences were found between patients with proven mutations and polymorphism variants when they were compared in terms of urinary cystine excretion, renal function, clinical onset age, drug usage, initial symptoms and operative history. In the comparison of the groups carrying SLC3A1 and SLC7A9 mutations, cystine excretion and the rates of the urinary cystine to creatinine were found significantly higher in the SLC3A1 group. 

 

Conclusions:

Polymorphism variants were not directly associated as disease factors but they were associated with disease susceptibility in 16 patients who had recurrent renal calculi formation, severe clinical process but no pathogenic mutation. Therefore, it is also thought that there are some other genes existed which may be responsible for the disease. Further studies are needed to determine phenotype-genotype correlation under the leadership of this study which is the first in our region.