From the Guidelines
Pulmonary fibrosis noted on chest X-ray (CXR) should be further investigated with high-resolution computed tomography (HRCT) of the chest to confirm the diagnosis and determine the specific type of fibrosis. When pulmonary fibrosis is suspected on a chest X-ray, additional diagnostic testing is necessary to confirm the diagnosis, determine the specific type of fibrosis, assess its severity, and guide treatment decisions 1. The next step typically involves HRCT of the chest, which provides much more detailed images of lung tissue than X-rays and is considered the gold standard imaging test for pulmonary fibrosis. Some key points to consider when investigating pulmonary fibrosis include:
- HRCT pattern is crucial in determining the diagnosis of idiopathic pulmonary fibrosis (IPF) and can be classified into usual interstitial pneumonia (UIP), probable UIP, indeterminate for UIP, or alternative diagnosis 1
- A multidisciplinary discussion is essential in making a confident diagnosis of IPF, especially when the HRCT pattern is indeterminate for UIP or probable UIP 1
- Pulmonary function tests (PFTs) should also be performed to assess lung capacity and function, including spirometry, lung volumes, and diffusion capacity
- Early and accurate diagnosis is crucial because pulmonary fibrosis is often progressive, and early intervention with antifibrotic medications may help slow disease progression in certain types of pulmonary fibrosis, particularly IPF 1.
From the FDA Drug Label
The FDA drug label does not answer the question.
From the Research
Pulmonary Fibrosis Investigation
Pulmonary fibrosis noted on chest X-ray (CXR) should be further investigated using high-resolution computed tomography (HRCT) to confirm the diagnosis and assess the extent of fibrosis.
- HRCT is an integral aspect of the evaluation of patients with suspected idiopathic pulmonary fibrosis (IPF) 2
- A study-site diagnosis of IPF on HRCT was regularly confirmed by core radiologists, with concordance between study-site and core radiologists regarding the diagnosis of IPF in 86% of cases 2
- The extent of reticulation and honeycombing on HRCT is an important independent predictor of mortality in patients with IPF 2
Disease Progression and Functional Decline
The relationship between radiographic progression and functional decline in IPF is unclear, but longitudinal changes in HRCT fibrosis scores and pulmonary functional variables can reflect clinically significant radiographic progression.
- A longitudinal increase in HRCT fibrosis score > 7% predicted lung transplant (LTx)-free survival significantly, with good specificity, but limited sensitivity 3
- The correlation between radiographic and functional progression was moderately significant, with HRCT progression and forced vital capacity (FVC) decline predicting LTx-free survival independently and significantly 3
- Changes in CT-related parameters during follow-up may have better predictive performance compared to baseline imaging parameters and pulmonary function tests (PFTs) for disease progression in IPF 4
Quantitative Chest Computed Tomography
Quantitative chest computed tomography can assess the progression of idiopathic pulmonary fibrosis (IPF) by segmenting and quantifying structural abnormalities seen on HRCT.
- Median changes in total lung volume, total lesion volume, and total lesion ratio were significantly higher in patients with worsening disease compared to those with stable disease 4
- Changes in lesion volume ratio were negatively correlated with changes in diffusing capacity of the lungs for carbon monoxide (DLco) during follow-up, and changes in pulmonary vessel-related parameters demonstrated positive correlation with DLco and forced vital capacity (FVC) 4
- Radiological imaging in IPF, particularly quantitative CT, is an evolving field that holds promise for increasingly accurate disease assessment and prognostication of IPF patients 5