Dendriform pulmonary ossification in military combat veterans: A case series

Dendriform pulmonary ossification (DPO) is a rare condition characterized by mature bone formation in the lung. DPO has been linked to various conditions, but little is known about the link between DPO and hazardous airborne exposures. We queried research databases of military personnel evaluated for deployment-related respiratory diseases at two occupational pulmonary medicine clinics (Colorado, USA) for diagnoses of DPO, and summarized demographics, Gulf War military deployment history, medical history, and pulmonary function testing. Chest imaging was independently reviewed and scored by a thoracic radiologist, and all cases had undergone lung tissue biopsy. We identified five male combat veterans with DPO, median age 49 years [range: 32-64]. All had deployed to Southwest Asia or Afghanistan during the First or Second Gulf War, and all reported frequent, intense exposure to diesel exhaust, burn pit emissions, and sandstorms. Lung physiology was abnormal in all cases. The most prevalent chest imaging and histopathology findings were airway-centric injury, inflammation, and retained particulate matter, suggesting substantial hazardous exposure during military deployment. This case series of a rare lung disease from the only two contemporary Colorado clinics serving previously deployed veterans highlights a potential link between airborne hazards and lung injury leading to DPO. A high index of clinical suspicion combined with a detailed occupational history may reveal additional exposure-related associations with DPO. Access to large medical databases of military veterans with linkage to exposure histories may further elucidate risk factors for lung injury with ossification, paving the way for targeted prevention.