Case 26-1977 — Progressive Respiratory Failure in a 46-Year-Old Man with a Positive Sweat Test

Presentation of CaseA 46-year-old office worker was admitted to the hospital because of dyspnea.He was in good health until five years previously, when a productive cough developed, accompanied by dyspnea. A physician made a diagnosis of bronchitis and bronchiectasis and prescribed tetracycline. Two years before entry dyspnea recurred, and he entered another hospital, where he was said to have a pseudomonas respiratory-tract infection and pulmonary emphysema. Multiple antibiotics were given. Seventeen months before admission measurement of the sweat electrolytes, performed with pilocarpine iontophoresis, revealed 459 mg of sweat in the left upper extremity and 452 mg in the . . .