Ureteritis cystica causing obstruction

We have described a 58-year-old man in whom an unusually fibroblastic ureteritis cystica at the ureteropelvic junction caused partial obstruction and ureteral colic. Local resection resulted in relief of renal pain and improved urinary flow through the ureter. Explanations for the unusual nature of the lesion and only partial relief of obstruction after surgical resection are proposed.