Ophthalmlic Involvement in Aggressive Histiocytosis X

The authors report the clinicopathologic features of an unusually aggressive form of histiocytosis X (Langerhans' cell histiocytosis) in a 36-yearold man who presented with diplopia and early development of pituitary failure from presumed involvement of the hypothalamus. Results of postmortem examination showed infiltrates of histiocytes and mixed inflammatory cells, with a variably dense desmoplastic tissue within the orbit and sclera bilaterally, the left optic nerve, choroid, emissary canals, and many other body systems including the pituitary, heart, lung, and gastrointestinal tract. Diagnosis was confirmed by immunohistochemical staining of large histiocytes within diseased areas, with anti-T6 and anti-S-100 antibodies.