Chemical analysis of renal stones from 377 Belgian patients by using qualitative or quantitative methods.

The renal stones of 377 patients from the Brussels' area have been studied by chemical methods; 239 stones were submitted to qualitative analysis and the other 138 to a quantitative analysis. The results of the study demonstrate that, in Belgium as well as in other Western countries like the USA and Great Britain, calcium oxalate, calcium phosphate and magnesium ammonium phosphate are, in decreasing order of frequency, the major constitutents of renal calculi. The fact that calcium oxalate-containing stones are mainly found in men associated with sterile urine, and magnesium ammonium phosphate stones in women associated with urinary infection, is confirmed in the present series. The percentage of uric acid-containing stones is similar to that in the USA and Great Britain, but lower than that observed in several European countries including France, Spain, Germany, Czechoslovakia and Sweden. A small group of Mediterranean patients living in Belgium show no specific pattern, suggesting that the formation of calculi could be more dependent upon environmental than upon ethnic factors.