Of possible etiologic significance with regard to pulmonary fibrosis of unknown cause is the small spate of cases of pulmonary histiocytosis without evidence of systemic spread reported since 1952. Of the 17 cases found in a review of the current literature, 14 were reported from military or Veterans Administration hospitals—5 from the same institution. All were diagnosed by lung biopsy. Rather than an occupational disease of military service, this is probably a reflection of the necessity for a definitive diagnosis for disposition. The following material is the description of a further case followed for 22 months.
A 28-year-old man was admitted to the U. S. Army Hospital, Fort Jay, on Feb. 21, 1957, because of abnormal findings on a routine separation chest x-ray. His chest film on entrance into the service in March, 1955, was normal. Past history revealed an attack of "virus pneumonia" in April of that year. Two