A 60-Year-Old Man With Dyspnea, Proximal Muscle Weakness, and Pulmonary Arterial Hypertension

A 60-year-old man with no significant medical history presented to the pulmonology clinic with 2 years of progressive weakness and shortness of breath. Showering and other activities of daily living caused him significant fatigue and dyspnea. He had a 20-pack-year smoking history, but no significant history of alcohol or illicit drug use. He did not take any prescribed or over-the-counter medications for chronic medical conditions and had never been on statin therapy. Vital signs were significant for an oxygen saturation of 91% on 4-L nasal cannula. He required up to 6 L of oxygen during a walk test. Physical examination showed mild inspiratory crackles in the lung bases, loud splitting of the second pulmonic valve (P2) with a right parasternal heave, and 2+ pitting edema in the lower extremities. There was muscle weakness, pain, and wasting of the proximal upper and lower extremities, particularly in his legs. He denied any joint pain, and there was no evidence of rash or dysphagia.