A 48-year-old woman has had increasing dyspnea with exertion for the past 5 months. She has had a cough with copious sputum production for the past 3 months. She has smoked 1 to 2 packs of cigarettes per day for the past 30 years. On physical examination her vital signs include temperature 37 C, pulse 83/min, respiratory rate 23/min, and blood pressure 135/90 mm Hg. Auscultation of the lungs reveals scattered crackles in lung bases.

Questions:

5.1 What do these findings indicate?

She is at increased risk for chronic obstructive pulmonary disease. The increased sputum production suggests chronic bronchitis, but to meet the definition, the problem should persist for at least 2 years.

5.2 What additional studies are indicated?

Pulmonary function testing reveals the following results:

5.3 What do these findings indicate?

Chronic bronchitis. The PFT shows a significantly reduced FEV1 and FEV1/FVC ratio. Note that in classical chronic bronchitis, the DLCO is relatively normal, since this is primarily an airways disease. Of course, there is considerable overlap between emphysema and chronic bronchitis, leading to the more generic application of "COPD" as the diagnosis. The diagnosis of chronic bronchitis is based upon a clinical, and not a pathologic, definition. Pathologic features may include submucosal gland hypertrophy and chronic inflammation, but these are non-specific findings.