Causes of pulmonary fibrosis

In a small number of pulmonary fibrosis cases, it’s possible to identify a specific cause.

Some causes are:

• being exposed to certain types of dust - including wood or metal dusts or asbestos
• being exposed to allergens - such as bird feathers or mould
• a side effect of a drug

Some types of pulmonary fibrosis occur when you have another condition such as rheumatoid arthritis or scleroderma.

In a very few cases, two or more members of a family may develop pulmonary fibrosis. But current research suggests the genetics of familial interstitial lung disease is complex and there is no clear inherited predisposition to develop pulmonary fibrosis.

In most types of pulmonary fibrosis a specific cause cannot be found. One of the most frequently occurring forms of fibrosis is called idiopathic pulmonary fibrosis (IPF). The word ‘idiopathic’ means there is no known cause.

Researchers recently set out some common types of interstitial lung disease, grouped by what causes them, in the diagram below. It is not agreed by all doctors and there’s lots of research underway to improve our understanding of the causes.

Classification of common interstitial lung diseases

Interstitial lung disease	Idiopathic disorders	Idiopathic pulmonary fibrosis Acute interstitial pneumonia (AIP) Idiopathic non-specific interstitial pneumonia (NSIP) Sarcoidosis
	Connective tissue and autoimmune disease	Scleroderma / progressive systemic sclerosis Systemic Lupus erythematosis (Lupus) Rheumatoid arthritis Polymyositis / dermatomyositis
	Occupational and environmental	Inorganic dust Organic dust Gases and fumes Radiation
	Drug-induced	Chemotherapeutic agent Radiation therapy Antiarrhythmics Antibiotics Anticonvulsants
	Infections	Viral infections Bacterial infections
	Genetic / inherited	Familial pulmonary fibrosis Hermasky-Pudlak syndrome

Adam Wallis and Katherine Spinks: The diagnosis and management of ILDs
British Medical Journal 2015

Next: Symptoms of pulmonary fibrosis >