[Natural history of renal calcium lithiasis. Data obtained from a cohort of 667 patients].

Between January 1st, 1988 and May 31st, 1989, 667 patients (419 men, 248 women) with radioopaque, non cystinic and apparently idiopathic (lack of severe renal disease) renal stones were entered in a prospective study. The data obtained at entry enabled us to build up, retrospectively, a quantified presentation of the natural history of calcium nephrolithiasis. At the time the disease was discovered the patients' mean age was 40.4 years, and its presence had been known for 7.9 years on average in both sexes. The mean number of stones formed by the patients was 3.5. In 218 of the 277 patients who had only one stone the nephrolithiasis had been present for less than 3 years, as compared with at least 6 years in the 184/252 patients who had 3 stones or more; this suggests that in many of the patients studied the stones had rapidly become symptomatic. Women had a significantly (chi 2: P less than 10(-3)) more frequent history of urinary tract infection than men, and notably more frequent episodes of febrile infection (31.5 percent in women, 7.1 percent in men). A familial history of nephrolithiasis was found in 34.7 percent of women and 31 percent of men, but its presence had no influence on the number of stones formed or on the duration of the disease. On the other hand, the stones were discovered significantly earlier in men who has a familial history of nephrolithiasis (37.3 years) than in those who had no such history (42 years; P less than 10(-3)). These data will be used as baselines to a prospective evaluation of the course of nephrolithiasis in these patients.