腎被膜に骨形成のみられた1例

Abstract

A case of bone formation in the renal capsule associated with pyelonephritis is presented. The patient was a 30-year-old woman and her chief complaint was general fatigue. Urinalysis showed moderate hematopyuria, but other laboratory examinations were normal. Calcification of the right kidney was found in roentgenograms and the excretory urograms showed the pelvocalyceal deformity at the region of the calcified shadow. Renal tumor was strongly suspected and right nephrectomy was performed. Grossly, the posterior capsule of the kidney was bony hard and could be cut with a knife but with difficulty. There was a large cystic cavity within the thickened renal capsule. Microscopically, well developed bone with hematopoietic bone marrow was found within the wall of the cyst in the capsule. Sections of the kidney showed the feature of chronic pyelonephritis. Bone formation in the renal capsule is very rare, and only two cases have been previously reported by Haber and Logan in 1967.