Cholecystitis and cholelithiasis associated with an intramural fasciitis-like proliferation and osseous metaplasia.

Fasciitis-like proliferations are said to be uncommon in the viscera; a fasciitis-like pattern of gallbladder injury may not be rare, but to our knowledge it has not been explicitly reported as such in any age group. Osseous metaplasia, or heterotopic bone, in the gallbladder is rare and has not to our knowledge been reported in a pediatric patient. We report a 7-year-old boy with sickle cell disease who presented with right upper quadrant abdominal pain. An ultrasonograph demonstrated a dilated common bile duct with sludge and stones. A cholecystectomy was performed. Grossly the gallbladder showed numerous pigmented choleliths, and histologically there was cholecystitis with a fasciitis-like fibrous proliferation containing scattered osteoclast-like giant cells and an area of osseous metaplasia. This report, describing a pattern that could be termed "cholecystitis ossificans," expands the histologic spectrum of chronic cholecystitis, a common disease with a poorly understood pathogenesis.