What test is used to investigate lung function in pulmonary fibrosis?

The lung diffusion test, also known as the diffusing capacity test, is crucial for assessing how well oxygen and other gases exchange between the air in the lungs and the blood in the pulmonary capillaries. In the context of pulmonary fibrosis, this test becomes particularly important because the thickening and scarring of the lung tissue can significantly impair gas exchange capabilities.

Measuring the diffusion capacity helps determine the severity of the disease and how well the lungs are functioning. Pulmonary fibrosis can lead to reduced diffusing capacity, and this test is sensitive to changes in lung function that are characteristic of interstitial lung diseases such as pulmonary fibrosis. It provides valuable information about the extent of the disease and aids in monitoring its progression over time.

While spirometry measures airflow and lung volumes, and imaging tests like chest X-rays and CT scans can help visualize the structural changes in the lungs, the lung diffusion test specifically assesses the alveolar-capillary membrane's ability to facilitate gas exchange, making it particularly relevant for evaluating pulmonary fibrosis.