[Relation between diet protein and calciuria in children and adolescents with nephrolitiasis].

PURPOSE: The objective was to evaluate the quality of diet and the relationship between protein diet and calciuria in children and adolescents with nephrolithiasis.

METHODS: Forty-nine children and adolescents (28 male and 21 female; 10.1 +/- 3.16 years old) with nephrolithiasis were included in study. Diet evaluation was performed over a 3 day period in order to determine nutrient consumption. The analysis of diets were carried out by DietWin Clínico 3.0 software. One 24-hour urine sample was collected for the measurement of calcium. Nutritional status was also assessed by Body Mass Index (BMI).

RESULTS: The diet of patients containe insufficient energy and calcium. High levels of protein (69.64 +/- 16.42 gm), mainly animal source (65.81 +/- 11.45%) and low levels of calcium (500.95 +/- 284.64 mg) was observed (95%). Analysis of 24 hour urine samples revealed that 25.0% of the patients presented hypercalciuria. A positive correlation (r = 0.26680) between animal protein intake and calciuria was found, in opposite of vegetable protein and calciuria correlation (r = -0.2675).

CONCLUSIONS: Animal protein of the diet has a significant effect in urinary excretion of calcium in patients with nephrolithiasis.