Rosai dorfman disease

sinus histiocytosis with massive lymphadenopathy. This disorder is a non-neoplastic, self-limiting disease of unknown cause. Typically patients have painless adenopathy, fever, elevated erythrocyte sedimentation rate, neutrophilic leukocytosis and hypergammaglobulinaemia. A marked proliferation of sinus histiocytes occurs in involved lymph nodes. Other sites of involvement include the upper respiratory tract, salivary glands, orbits, eyelids, testes and bone.

The bone manifestations of this disease usually occur as multiple solitary asymptomatic osteolytic lesions involving principally the long tubular bones. However, the skull, pelvis, sternum, vertebral bodies, phalanges, metacarpals and ribs may also be involved.