Case report: Erdheim-Chester disease: polyostotic sclerosing histiocytosis.

Erdheim-Chester disease is characterised by diffuse metaphyseal and diaphyseal sclerosis of long tubular bones of the appendicular skeleton. In addition, there is an inconstant tendency to visceral involvement by lipo-granulomatous infiltration. Histologically, this condition has marked similarities to Hand-Schuller-Christian disease. A further case is presented which supports the view that Erdheim-Chester disease is part of the spectrum of histiocytoses and not a distinct pathological entity. Polyostotic sclerosing histiocytosis would be an appropriate alternative label for this condition.