Idiopathic Constrictive Bronchiolitis in an Active Duty Soldier.

Constrictive bronchiolitis is characterized by fibroproliferative thickening of the bronchiolar walls causing narrowing of the bronchiolar lumen, which may progress to the complete obliteration of bronchioles, resulting in progressive dyspnea and ultimately respiratory failure. Active duty service members returning from deployment with toxic exposures such as "burn pits" are known to be at risk for this condition. Other proposed etiologies for this condition include inhalation (nitrogen oxides, ammonia, welding fumes, aerosols [nicotine, diacetyl, and vitamin E acetate]), infection (respiratory syncytial virus, adenovirus, or Mycoplasma pneumoniae), rheumatic diseases, and graft-versus-host disease (lung or hematopoietic cell transplantation). Uncommonly, constrictive bronchiolitis can also be idiopathic. Here we present a case of a young active duty soldier with idiopathic constrictive bronchiolitis without any known risk factors for this disease. The goal of this case presentation is to help the military physician better understand this condition, including identification of this disease process, underlying etiologies, risk factors, and treatments available.