[Epidemiological study on urolithiasis in Mie Prefecture. 1. Present status in 1985]

To determine the present status of urolithiasis in Mie Prefecture, we analyzed the 1,314 patients of urolithiasis at 17 Departments of Urology and 2 Departments of Medicine in 1985. The ratio of male patients to female patients was 2.6 to 1. The most frequent incidence of urolithiasis was observed in Iinan county. The incidence of urolithiasis in the urban area was the same as that in the country. Most of the stones (96.9%) were in the upper urinary tract. The incidence of lower urinary tract calculi tended to be high in southern Mie Prefecture. The ratio of upper urinary tract calculi to lower urinary tract calculi in the urban area was the same as that in the country. The peak incidence in males was in the forties, while that in females was in the fifties. The average age was 44.5 years old. Ureterolithotomy was the most frequent (37.5%) surgical therapy, percutaneous nephrolithotomy and shock wave lithotomy done in 8.0% and 6.3%, respectively. The most frequent component of the urinary tract calculi was calcium oxalate and/or calcium phosphate (84.0%). The incidence increased in summer (April through September).