Evaluation of Prevalence, Molecular and Genetic Backgrounds of Calcium-Based stones among Patients with Renal Calcular Disease in Mansoura Urology and Nephrology Center

Back ground: Nephrolithiasis is a prevalent disease with high morbidity, the incidence and prevalence of nephrolithiasis has risen worldwide. Calcium nephrolithiasis may be considered as a complex disease having multiple pathogenic mechanisms and characterized by various clinical manifestations. Both genetic and environmental factors may increase susceptibility to calcium stones. Polymorphisms of vitamin D receptor (VDR), calcium-sensing receptor gene (CASR) and AGXT have been associated with risk of urolithiasis, but, with inconsistent results and lack data from Egyptian population.

Objective: Therefore, the present study aims to investigate the prevalence, mutational profile for these genes in patients with Ca-based stones, admitted to Mansoura Urology and Nephrology Center.

Methodology: In this study, employing sequencing of the coding exons of the calcium-sensing receptor gene (CASR), vitamin D receptor (VDR) and AGXT for a 50 of Egyptian calcium kidney stone-formers and 20 control subjects. The results of the mutational profile data will be correlated with risk of stone recurrence over 2 years.

Inclusion Criteria:

• All patients with unilateral or bilateral renal stones (de novo or recurrent) who were candidates for endoscopic or surgical intervention were included. Metabolic workup was done for selected patients with radio-opaque stones, while genetic testing was done for those with dominant Ca composition proven by postoperative stone analysis. Thirty healthy individuals with no urologic abnormalities were involved as control cases. Patients with renal calculi for whom metabolic and genetic testing were performed are designated "α" cases.

Exclusion Criteria:

• For metabolic and genetic testing, patients with a well-known lesion precipitating stone disease were excluded e.g. ureteric stricture, ureteropelvic or ureterovesical junction obstruction, urinary diversion, history of ureterovesical re-implantation as well as patients with non-Ca stones by post-operative stone analysis

All patients with unilateral or bilateral renal stones (de novo or recurrent) who were candidates for endoscopic or surgical intervention