This case report describes total parenteral nutrition (TPN) -associated crystalline precipitates occluding the pulmonary artery branches in a Crohn's disease patient who survived. These precipitates caused focal vascular disruptions and alveolar granulomas. High-resolution CT (HRCT) scan demonstrated a diffuse ground-glass appearance. Pulmonary function tests showed severe ventilatory defects, arterial hypoxemia, and decreased oxygen saturations. Energy dispersive x-ray analysis (EDAX) of the patient's lung biopsy and expectorant demonstrated similar patterns, supporting crystal migration into the alveoli. Treatment included broad-spectrum antibiotics, anticoagulation, corticosteroids, and daily pulmonary toilet. The patient required continuous supplemental oxygen for two months and then was able to use it intermittently. This patient survived widespread pulmonary vascular occlusions secondary to precipitation and crystallization of TPN solution, with moderately severe residual deficits in exercise tolerance and chest x-ray abnormalities. This case underscores the importance of surveillance and recognition and of TPN-associated complications by health care workers.