[Comparative study of 24-hour calciuria and urinary calcium/creatinine ratio in children over 4 years of age].

The relationship between 24 hour urinary calcium excretion (U Ca/24 h) and urinary calcium/creatinine ratio (U Ca/creat) measured for morning and evening urine samples was studied in 56 children aged 4-15 years and hospitalized for benign conditions. Depending on the length of hospitalisation, 1 to 3 determinations of U Ca/24 h and U Ca/creat ratio were carried out for each child. Mean +/- SD U Ca/24 h was 0.05 +/- 0.058 mmol/kg. Mean U Ca/Cr, expressed in mmol/mmol, was 0.368 for total 24 h urine, 0.358 for the morning sample and 0.358 for the evening sample respectively. A good correlation was found between U Ca/24 h and 24 h U Ca/Cr ratio (r = 0.89), morning U Ca/creat (r = 0.83) and evening U Ca/creat ratio (r = 0.81) respectively. It is concluded that determination of the U Ca/Cr ratio for morning or evening urine samples is an efficient means of detecting hypercalciuria.