Studies on urolithiasis in Israel.

The composition of 1,000 kidney stones in our area of Israel was analyzed. The predominant stones were a combination of calcium oxalate and calcium phosphate, and uric acid. We used chemical analysis to determine the relative incidence of urinary calculi in 500 patients of various ages and ethnic groups. The incidence of calcium oxalate and calcium phosphate calculi (44 per cent) in Jews born in Israel was lower than in other ethnic groups (54 to 64 per cent). The incidence of uric acid stones in Jews born in Israel, Lebanon, Iran, Iraq and Syria, and the Ashkenazim (16 to 29 per cent) was 2 to 3 times higher than in other groups. In more than 60 per cent of the patients urolithiasis developed after they were 20 years old. The age at onset was significantly younger in Jews born in Israel (25.7 per cent) and North Africa (13.8 per cent), and in Arabs (18 per cent).