METABOLIC ABNORMALITIES IN PATIENTS WITH CALICEAL DIVERTICULAR CALCULI

Abstract

Purpose We determined the incidence and spectrum of metabolic abnormalities in patients with caliceal diverticular calculi. Materials and Methods Five men and 9 women with caliceal diverticular calculi underwent metabolic evaluation, including determination of serum electrolytes, calcium, phosphate and uric acid, and 24-hour urinary volume, creatinine, calcium, oxalate, uric acid and citrate. Results Of the 14 patients 7 (50%) had urinary excretion abnormalities promoting stone formation, including hypercalciuria in 3, hyperoxaluria in 1, hypercalciuria 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 distant from the involved caliceal diverticular stone and 5 (55.6%) of these 9 had definable metabolic disorders. However, there was no statistically significant difference in urinary excretion values between patients with or without a history of additional extra diverticular stones. Conclusions Urinary stasis alone does not explain stone formation in a significant number of patients with caliceal diverticular calculi. Rather, the local physiological environment of the urine likely has a predisposing role and evaluation for metabolic abnormalities should be considered. In some patients cure may be effected by treating the stone and any associated metabolic disorders rather than the diverticulum.