A 58-year-old man was admitted to the hospital because of respiratory distress and hypotension.Seven years before admission, a routine radiograph of the patient's chest had been reported to show a "black spot" in a lung. He declined follow-up examinations. Fifteen months before admission, he began to have a chronic cough productive of clear sputum, progressive exertional dyspnea, fatigue, and weight loss. Seven months before admission, he immigrated to the United States from a Caribbean island to be cared for by his daughters who resided in this country. Two weeks later, he came to this hospital.The patient had been a construction worker for several years, with exposure to sprayed pesticides. He drank alcohol heavily but never smoked. There was no history of chest pain, hemoptysis, wheezing, fever, chills, sweats, tuberculosis or exposure to it, hypertension, coronary artery disease, or diabetes mellitus, and there were no risk factors for human immunodeficiency virus (HIV) infection except for several recent sex partners.The temperature was 37.2°C, the pulse was 80, and the respirations were 18. The blood pressure was 105/70 mm Hg.Examination revealed cachexia and diminished breath sounds at the left base and the lower half of the right lung and fine inspiratory crackles over the right middle lobe. No wheeze was heard. A grade 2 holosystolic murmur was present along the left sternal border. No peripheral edema, digital clubbing, or cyanosis was present.The urine was normal. Laboratory tests were performed (Tables 1 and 2). An electrocardiogram showed a normal rhythm at a rate of 81, with an R-wave axis of ϩ 73 degrees and right atrial enlarge-ment; the R waves were absent in leads V 1 and V 2 , with low-to-inverted T waves in leads V 1 through V 3 . Radiographs of the chest (Fig. 1) showed volume loss in the left lung, with a leftward shift of the mediastinum and trachea. There was extensive air-space disease in the left lung, with focal cavitation or cyst formation and bronchiectasis, especially in the upper lobe. The right lung was hyperinflated, with air-space disease and multiple nodular opacities, particularly in the perihilar region and in the lower lobe, where many of the opacities were confluent. The left costophrenic angle was blunted, a finding consistent with pleural effusion or thickening. The heart border was obscured by the lung disease. Microscopical examination of sputum smears showed a few acid-fast bacilli. Cytologic studies of the sputum revealed no tumor cells. A skin tuberculin test (purified protein derivative, 5 TU) was strongly positive; a test for mumps antigen was positive, and a test for candida antigen was negative. A serologic test for HIV antibodies was negative.The patient was admitted to a negative-pressure isolation room and was given isoniazid, rifampin, pyrazinamide, ethambutol, and pyridoxine. He remained afebrile, and his condition began to improve, with a diminished cough, after a 14-day course of *The control value was 11 seconds.