DISCUSSION: Systemic mastocysotosis is a rare disease and involvement of the skeletal muscle, gastrointestinal tract, and lymph nodes is common. Pulmonary involvement is less common and may occur in less than 20% of patients with systemic mastocytosis. Symptoms can include cough, dyspnea, and asthma like symptoms. Findings on chest radiograph include interstitial fibrosis and pulmonary nodules. CT findings include nodular and reticular opacities as well as mediastinal lymph node enlargement.