[Detection of metabolic disorders as a cause of urolithiasis in clinical practice]

Metabolic disorders are the most frequent risk factor for the development of urolithiasis. They are manigenic substances or deficiency of inhibitors of crystalgenic substances or deficiency of inhibitors of crystallization and aggregation. The authors use for their diagnosis a modification of Pak's procedure. It involves examination of 24-hour urine with the patient on a low-calcium diet, supplemented by urine examination on fasting and after a 1000 mg calcium load. The procedure includes also examination of serum and bacteriological examination of urine. A total of 93% of patients with calcium lithiasis had a metabolic disorder, 42% suffered from idiopathic hypercalciuria, 32% from hyperuricosuria, 19% from hyperoxaluria, 15% from magnesium deficiency and 38% from hypocitraturia. On the other hand, patients with uric acid lithiasis had a detectable metabolic disorder only in 62%. Active detection of metabolic disorders is essential for the introduction of effective, specific metaphylaxis of urolithiasis.