A 63-year-old nonsmoking white man presented to the clinic with a 2-year history of cough. The cough was dry, and it was worse at night. The cough had begun after an upper respiratory tract infection and a trip to South America. The patient was prescribed antibiotics by a family physician but had no improvement; he was then given a combination inhaler (salmeterol and fluticasone) and had minimal improvement.This patient has chronic cough, which is defined as a cough lasting more than 8 weeks. In a nonsmoker, the most common causes are the upper-airway cough syndrome (allergic, nonallergic, or infectious), asthma, and gastroesophageal reflux disease (GERD). This patient has features suggestive of GERD or the upperairway cough syndrome after an upper respiratory tract infection. Although the long duration of cough may suggest mild asthma, this condition should have improved substantially with the correct use of a combination inhaler.The patient's medical history included at least 5 years of intermittent arthralgias and myalgias and a 2-year history of night sweats (now resolved) before this presentation. The arthralgias occurred in his neck, shoulders, wrists, hands, hips, and ankles; episodes would last 2 weeks on average, followed by complete recovery. He was assessed by a rheumatologist during the first 2 years after the onset of these symptoms and had negative results on tests for antinuclear antibody (rheumatoid factor, extractable nuclear antigens, and anti-cyclic citrullinated peptide antibodies) and HLA-B27. A tuberculin skin test, chest radiography, and ultrasonography of the abdomen were also negative. Additional medical history included pitting edema in the lower limbs bilaterally for the past 2 years (attributed to venous stasis), for which the patient used compression stockings. There was no other clinically significant medical history. The patient had never smoked, and he drank minimal amounts of alcohol. He had no pets. His only medications were the inhaler and ibuprofen (as needed).In this Journal feature, information about a real patient is presented in stages (boldface type) to an expert clinician, who responds to the information, sharing his or her reasoning with the reader (regular type). The authors' commentary follows. The New England Journal of Medicine Downloaded from nejm.org at EMORY UNIVERSITY on August 5, 2015. For personal use only. No other uses without permission.