A 2-month-old female with worsening cough, respiratory distress and an abnormal chest X-ray was referred to our institution for further evaluation of suspected scimitar syndrome. She was found to have normal pulmonary venous drainage with a large patent ductus arteriosus and severe pulmonary arterial hypertension. Chest CT was suggestive of interstitial lung disease. Wedge lung biopsy revealed alveolar simplification and patchy pulmonary interstitial glycogenosis. A definitive diagnosis of Filamin A deficiency was made with genetic studies. The patient is currently showing clinical improvement on systemic glucocorticoid therapy.