The definitive management of patients with a stone bearing calyceal diverticulum should include both management of the diverticulum and a metabolic workup.
This was nicely demonstrated by the research teams from Indianapolis and the University of Chicago (abstract 1535) in a retrospective analysis of patients who underwent treatment of symptomatic calyceal diverticular calculi. They found that compared to patients with calcium oxalate (CaOx) stones, the calyceal diverticular CaOx calculi group of patients had similar urinary stone risk parameters. Compared to non-stone forming patients these two groups had significantly more hypercalciuria and supersaturation (SS) of CaOx. However, urine aspirated directly from the occluded diverticulum had the lowest SS CaOx compared to the ipsilateral and contralateral renal pelvis. This data supports the hypothesis that a combination of urinary stasis and metabolic abnormalities contribute to the pathogenesis of calyceal diverticular calculi. For patients with calyceal diverticular calculi it is important to resolve the obstruction of the diverticulum and perform a complete metabolic evaluation to provide comprehensive medical management of the stone disease.