[First report on a cholesterol granuloma of the urinary bladder (cyst of the urachus) (author's transl)].

The authors present a report on a successfully operated cholesterol granuloma of the urinary bladder in a 73 years old female. As suggested by its topography, the granuloma is best explained, in terms of its origin, as a cyst of the urachus. Its development is thought to be due to an inflammatory mechanism with resultant tissue destruction which triggered the endogenous release of the cell-bound cholesterol. These cholesterol substances, when freely deposited in the tissue, appear to give rise to extensive granulomatous foreign body reactions.