A 52-Year-Old Man Who Smokes With Rapidly Progressive Respiratory Failure

A 52-year-old White man, who currently smokes, was admitted to the medical ICU with worsening shortness of breath. The patient was dyspneic for a month and had been clinically diagnosed with COPD by his primary care doctor and started on bron-chodilators and supplemental oxygen. He had no known medical history or recent illness. His dyspnea worsened rapidly over the next month, prompting admission to the medical ICU. He was on high -flow oxygen followed by noninvasive positive pressure ventilation and then mechanical ventilation. He denied cough, fever, night sweats, or weight loss at the time of admission. There was no history of work-related or occupational exposures, drug intake, or recent travel. Review of systems was negative for arthralgia, myalgia, or skin rash.