Fibrosis refers to the thickening and scarring of connective tissue, usually as a result of injury or long-term inflammation. This scarring can occur in various organs, including the lungs, liver, kidneys, and heart, and it disrupts the normal functioning of the affected organ.In the lungs, fibrosis is commonly referred to as pulmonary fibrosis, which occurs when the lung tissue becomes damaged and scarred, making it difficult for the lungs to work properly. The scarring can be caused by chronic conditions, environmental exposures (like asbestos or dust), infections, autoimmune diseases, or can occur without a known cause (idiopathic pulmonary fibrosis)