
A 22-year-old man presents to theemergency department with a2-week history of a worsening nonproductive,irritating dry cough andexertional dyspnea. The patient hasbeen otherwise healthy. He deniesfever, rigors, night sweats, hemoptysis,chest pain, palpitations, orthopnea,paroxysmal nocturnal dyspnea,ankle edema, and lymphadenopathy.





























































































































