A 39-year-old man presented with progressive shortness of breath and a 1-day history of decreased urine output. He had a history of mild COPD for which he occasionally used albuterol inhalers. Over the prior 3 months, however, he had developed gradually increasing dyspnea and was using his inhalers several times a day with little relief. He also described 3 months of progressive lower extremity weakness. He had suffered a series of falls, the last resulting in continuous right hip pain. Prior to hospital admission, he had been in bed for 2 months because of weakness and pain. His sister brought him to the emergency department because of dyspnea. He had a 75-pack-year smoking history and a distant history of alcohol abuse.