Howard S. Van Ordstrand

Primary Pulmonary Histiocytosis X*

“Primary” pulmonary histiocytosis X is a disease of unknown etiology. The clinical and pathologic features of 11 cases diagnosed by lung biopsy are reviewed. The disease was found more often in males and ages ranged from three months to 59 years. The children reported appear to be unique as no others with isolated pulmonary disease were encountered in a review of the literature. Electron microscopic observations in one case revealed rod-like intracytoplasmic inclusions in some histiocytes. Although previously described in skin, bone and pulmonary lesions of histiocytosis X, the nature of these inclusions is not known. Six patients died, four apparently due to effects of pulmonary disease, one patient of pneumonia and another in an auto accident two years after the diagnosis had been confirmed.