Pulmonary fibrosis is a progressive lung disease that involves scarring and thickening of the lung tissues. There are several types of pulmonary fibrosis, but the four stages commonly associated with idiopathic pulmonary fibrosis (IPF) are:
- Stage 1 (mild): In this stage, there is mild scarring and inflammation of the lung tissue. The symptoms may not be noticeable, and lung function tests may show only a slight decrease in lung capacity.
- Stage 2 (moderate): In this stage, the scarring and inflammation have spread to more areas of the lungs, and there is more noticeable lung damage. Symptoms such as shortness of breath and coughing may be more pronounced, and lung function tests will show a more significant decline in lung capacity.
- Stage 3 (severe): In this stage, the scarring and inflammation have spread throughout most of the lungs, and there is significant lung damage. Symptoms such as shortness of breath, coughing, and fatigue may be severe, and lung function tests will show a significant decrease in lung capacity.
- Stage 4 (end-stage): In this stage, the scarring and damage are extensive, and the lungs are no longer able to function properly. Symptoms may be very severe, and the patient may require oxygen therapy or lung transplantation to survive.