Brief Answer:
Causes of lung scarring

Detailed Answer:
Hello and welcome,

Lung scarring (pulmonary fibrosis) can happen from a number of different diseases and injuries. I am thinking that you are wanting to know what diseases cause the scarring? Or do you mean what is the physical mechanism that results in this?

I'll answer the first possible question - what diseases and conditions cause it. If that is not what you meant, please let me know.

1. Some autoimmune and connective tissue disorders such as Lupus, scleroderma, and sarcoidosis, and granulomatosis.
2. Lung infections (TB, sometimes pneumonia)
3. The following medications can have lung scarring as a complication: amiodarone, bleomycin, busulfan, methotrexate,apomorphine, and nitrofurantoin.
4. Inhaled substances including silica, asbestos, some metals and gases and chemical sprays.
5. Hypersensitivity pneumonitis, such as from inhaling sileage contaminated with molds or bacteria.
6. Chest radiation such as from radiation therapy to treat cancer.
Cigarette smoking can increase the risk or make the illness worse.
7. Cigarette smoking can increase the risk of scarring, and make the scarring process of any of the above situations worse.

I hope this information helps.

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