Question

Pulmonary function testing is done on a patient with a 65-pack-year history of smoking. The following pulmonary function data is recorded:

Percent of Pred Actual value
Fev1.0 58
FEF200-1200 75
FEF25-75 52
SVC 88
FVC 81
DLCO 18 CO/min/mmHg
Which of the following most likely represents the patient's condition?
1) kyphosis
2) emphysema
3) cystic fibrosis
4) chronic bronchitis

Answer 1

With a significantly reduced FEV1/FVC ratio and low DLCO, the pulmonary function test results suggest obstructive lung disease, likely emphysema, particularly in a patient with a significant history of smoking (2).

Step-by-step explanation:

Pulmonary function testing is used to assess lung function and diagnose various pulmonary conditions. A patient with a 65-pack-year history of smoking presents with pulmonary function data such as FeV1.0 at 58%, SVC at 88%, FVC at 81%, and particularly low DLCO (diffusing capacity for carbon monoxide) at 18 CO/min/mmHg. These results, especially the reduced FEV1/FVC ratio and low DLCO, suggest the presence of obstructive lung disease, typical of conditions such as emphysema or chronic bronchitis.

In emphysema, damage to the alveoli and airway collapse leads to increased resistance and obstruction, which correlates with the low FEV1/FVC ratio seen here, indicating an obstructive pattern. Furthermore, the significantly reduced DLCO value implies impaired gas exchange, a hallmark of emphysema due to the destruction of lung tissue. Therefore, of the options provided, the most likely diagnosis for the patient's condition is emphysema.