Epidemiologic study on urolithiasis in Mie prefecture. 2. Present status in 1988

To determine the current status of urolithiasis in 1988, in comparison with that in 1985, we analyzed the 1937 patients of urolithiasis at 17 departments of urology in Mie Prefecture and 2 departments of urology in Wakayama Prefecture. The ratio of male to female patients was 2.6 to 1.0. Geographically, the number of urolithiasis patients was most frequently distributed in Matsusaka City. The frequency of urolithiasis in the urban area was almost the same as that in the rural area. Most of the stones (96.3%) were in the upper urinary tract. The frequency of lower urinary tract calculi tended to be high in southern Mie Prefecture. The ratio of the upper urinary tract calculi to the lower urinary tract calculi in the urban area was higher than in the rural area. The age distribution in males was in the forties, while that in females was in the fifties. The average age was 46.4 years old. The surgical treatment was performed in 671 patients (34.6%) and the extracorporeal shock wave lithotripsy (ESWL) was the most frequent mode of treatment (85.0%), followed by cysto-lithotripsy (4.2%) and percutaneous nephro-uretero-lithotripsy (2.4%). The most frequent component of the urinary tract calculi was calcium oxalate and/or calcium phosphate (81.7%). The stone patient increased in the number during the summer season (July, August and September). In conclusion, in 1988 when the ESWL treatment started in Mie Prefecture, the epidemiologic features of urolithiasis was characterized as follows: the number of patients increased and the broad application of the ESWL treatment resulted in the decreased number of patients with spontaneous discharge and the increased number of patients with recurrent stones and with bilateral or multiple complex stones