The diagnostic value of the phosphate levels in serum and 24-hour urine samples in patients with recurrent renal stone disease

Objective: The aim of this study is to investigate the value of phosphate levels in serum and urine in patients with recurrent renal stone disease. Materials and methods: The patients (n: 60) were divided into two groups as first-time stone disease (group 1) and recurrent renal stone disease ( group 2). The demographical datas and their historical information were recorded and physical examination was done. The sera and urine for 24 hr were obtained from patients to measure electrolyte levels especially phosphorus. In addition, based on presenting serum phosphate levels, patients were divided into the hypophosphatemia group, less than 2.5 mg/dl; normophosphatemia group, between 2.5-5.2 mg/dl; and hyperphosphatemia group greater than 5.2 mg/dl. Results: The mean age of study group was 45 (21-70) years. Thirty-six patients (60%) were in group 1 and 24 patients (40%) were in group 2. No statistically correlation was found between stone recurrence and phosphate levels both in serum and urine. There was only a statistical association of K levels in 24-hour urine samples between group 1 and 2. Conclusion: There was no significant association between stone recurrence and initial phosphate levels in the serum or in urine. We do not propose to determine phosphate levels routinely in management of patients with stone disease.