Caliceal diverticular calculi: Is there a role for metabolic evaluation?

Purpose: We report our experience with the treatment and incidence of metab olic abnormalities in patients presenting with caliceal diverticular stones . Materials and Methods: We retrospectively evaluated 49 patients with calice al diverticular stones (group 1) and 44 with simple renal stones (group 2). Each group successfully underwent percutaneous treatment. Mean stone size was 1.7 and 2.5 cm. in groups 1 and 2, respectively. Metabolic evaluation w as available in 25 group 1 and 22 group 2 patients. Mean followup was 73.2 and 70.8 months, respectively. Results: We achieved a stone-free rate of 95.9% in group 1 and 100% in grou p 2. There was no metabolic abnormality in 75% of the group 1 patients, whi le 12% had type II absorptive hypercalciuria, 8% hyperuricosuric hypercalci uria and 4% hyperoxaluria. There were no metabolic abnormalities in 22.7% o f the group 2 patients, while 9%, 18% and 9% had types I to III absorptive hypercalciuria, respectively, 13.6% hyperuricosuric hypercalciuria, 13.6% h yperoxaluria, 4.5% hypocitruria and 9% type II absorptive hypercalciuria as sociated with hypocitruria. Conclusions: Our results reveal a low incidence of associated metabolic abn ormalities in patients with caliceal diverticular stones. Thus, we believe that metabolic abnormalities do not promote caliceal diverticular calculous formation.