[Diagnosis, prevention and treatment of renal and urinary tract lithiasis]

Kidney and urinary stone disease is a major public health problem which requires a systemic clinical and biochemical evaluation to establish a precise diagnosis and well oriented therapy. This study reviews the results of a protocol designed to establish the metabolic abnormalities that occurred in 626 consecutive renal stone patients studied in two periods; group I (1979-1987) 441 cases and group II (1987-1989) 185 cases. The group I included the following determinations before and after a five day oral calcium load: serum and 24 hr urine electrolytes, divalent cations, phosphate, uric acid, cystine, glomerular filtration rate, parathyroid function evaluation with PTH and Tm Phosphate and since 1982 also (Ia) cAMP. In group II we also determined inhibitors of crystallization (magnesium and citrate) and promoters of nucleation (oxalate). In 185 cases of group I, we monitored months of follow up after metabolic evaluation and the number of stones formed per patient/year before and after treatment was begun. In group I we detected some variety of metabolic abnormality in 88.2 percent of our patients and in group II increased to 96.2 percent. A two year follow up was recorded in 55 percent and four year follow up in 39 percent of our cases. The stone/patient/year formation rate before treatment was 2.8 and significantly decreased to 0.8 after treatment. The highly diagnostic efficiency, the long term follow up and the adequacy of treatment significantly decreased stone activity in this group of patients. We concluded that this protocol should be included in the systematic evaluation of kidney stone patients.