Rosai-Dorfman disease. Extranodal sinus histiocytosis in three co-existing sites. A case report.

A 73-year-old woman presented with mild anterior uveitis, ipsilateral optic neuropathy, and ipsilateral skin nodules. A compressive mass at the level of the orbital apex and sphenoid wing was found on cranial magnetic resonance imaging. Biopsy of the skin nodules revealed histopathologic evidence of sinus histiocytosis with massive lymphadenopathy, or Rosai-Dorfman disease (RDD). Systemic investigations failed to show any massive lymphadenopathy, making this a case of extranodal RDD. This is a salient case in that it proposes three simultaneous and separate sites of involvement by extranodal RDD. It also exemplifies that RDD should be a suspect diagnosis even in the absence of lymphadenopathy.