METABOLIC ABNORMALITIES IN PATIENTS WITH CALICEAL DIVERTICULAR CALCULI

Purpose: We determined the incidence and spectrum of metabolic abnorma lities in patients with caliceal diverticular calculi. Materials and M ethods: Five men and 9 women with caliceal diverticular calculi underw ent metabolic evaluation, including determination of serum electrolyte s, calcium, phosphate and uric acid, and 24-hour urinary volume, creat inine, calcium, oxalate, uric acid and citrate. Results: Of the 14 pat ients 7 (50%) had urinary excretion abnormalities promoting stone form ation, including hypercalciuria in 3, hyperoxaluria in i, hypercalciur ia combined with hyperuricosuria in 1 and hyperoxaluria combined with hyperuricosuria in 2. Two patients had a history of gout while another had radiographic evidence of medullary sponge kidney. Of the patients 9 (64.3%) had a history of synchronous or metachronous calculi distan t from the involved caliceal diverticular stone and 5 (55.6%) of these 9 had definable metabolic disorders. However, there was no statistica lly significant difference in urinary excretion values between patient s with or without a history of additional extra diverticular stones. C onclusions: Urinary stasis alone does not explain stone formation in a significant number of patients with caliceal diverticular calculi. Ra ther, the local physiological environment of the urine likely has a pr edisposing role and evaluation for metabolic abnormalities should be c onsidered. In some patients cure may be effected by treating the stone and any associated metabolic disorders rather than the diverticulum.