title: Pulmonary blue bodies.
abstract: Pulmonary blue bodies are intra-alveolar laminated basophilic concretions of uncertain etiology. Blue bodies were studied in lung biopsy specimens from 10 patients. The patients ranged in age from 47 to 69 years and were predominantly men. Three had a history of overt exposure to environmental dusts such as sawdust and asbestos, and two showed occasional ferruginous bodies in the lung, raising the possibility of pneumoconiosis. In eight cases there was interstitial pneumonitis, which resembled desquamative interstitial pneumonia by light microscopy but which was often seen to be patchy and asymmetrically distributed in the lung by chest x-ray examination. Of two other patients, one had xanthogranulomatous inflammation and the other, necrotizing granulomatous inflammation. Light and electron microscopic, histochemical, microchemical, and x-ray diffraction studies of blue bodies were also performed. Calcium carbonate is a major component of blue bodies and is responsible for their birefringence in unstained sections and ready solubility in acid solutions. Blue bodies also contain a mucopolysaccharide matrix and iron. We offer the hypothesis that blue bodies (calcium carbonate) are a product of histiocytic catabolism.
mesh_terms: D000368:Aged; D005260:Female; D006651:Histocytochemistry; D006801:Humans; D008297:Male; D008832:Microchemistry; D008854:Microscopy, Electron; D008875:Middle Aged; D011014:Pneumonia / Q000000981:diagnostic imaging / Q000473:pathology*; D011650:Pulmonary Alveoli / Q000000981:diagnostic imaging / Q000473:pathology*; D011859:Radiography; D013194:Staining and Labeling; D014961:X-Ray Diffraction