[A histiocytosis X without histological findings: a new entity of histiocytosis X].

: Histiocytosis X is a disorder of the reticuloendothelial system with manifestations usually present in the form of one of three entities, namely; Letterer-Siwe disease, Hand-Schuller-Christian disease and eosinophilic granuloma of the bone. A 32-year-old female was admitted to our hospital in July 1990 because of a bilateral diffuse granular abnormal shadow in the chest. She had a history of bilateral pneumothorax in July 1987. She had been suffering from diabetes insipidus since October 1987, and amenorrhea since January 1989. Miliary tuberculosis, fungus disease, pneumoconiosis, sarcoidosis and collagen disease of the lung were excluded by laboratory examinations, and by observation of the clinical course. Histiocytosis X often combines pneumothorax, diabetes insipidus, amenorrhea and an abnormal radiograph of the chest. We suspected this case was one of Histiocytosis X. But, in her lung biopsy, neither Langerhans cells nor Birbeck granules were found. Furthermore S100 protein immunoperoxidase stain was negative. Therefore, we posit the existence of a new and different subtype of Histiocytosis X without histological findings.