A 60-year-old man with recurrent pneumonias.

R adiographic studies (Figs 1–4) were obtained from a 60-year-old man with recurrent pneumonias for the past 15 years. He has chronic foulsmelling sputum, increasing shortness of breath, and increasing supplemental oxygen requirements. He reports a 50–pack-year history of tobacco use, but has not smoked for 12 years. In addition to bilateral crackles and rhonchi posteriorly, he exhibits digital clubbing. His FEV1 is 1.52 L (48% of predicted); FVC, 2.4 L (61% of predicted); and FEV1/FVC, 0.62. While he is receiving 5 L of oxygen by nasal cannula, his arterial blood gas analysis reveals a Po2 of 60 mm Hg, Pco2 of 41 mm Hg, and pH of 7.43. Sputum culture grows Pseudomonas species. Which one of the following statements concerning this case is not true?