In short: Interstitial lung diseases are a group of more than 200 conditions that affect the lung tissue itself and sometimes cause scarring (fibrosis). Identifying the exact type matters, because treatment differs greatly from one disease to another.
Symptoms
Shortness of breath that gradually worsens with exertion, and a persistent dry cough. On examination, the doctor may hear fine crackles at the bases of the lungs.
Main types
- Idiopathic pulmonary fibrosis (IPF)
- Lung disease associated with connective tissue and rheumatologic diseases
- Hypersensitivity pneumonitis, following an environmental exposure
- Sarcoidosis
- Lung injury caused by medications or occupational exposure
How it is diagnosed
High-resolution CT (HRCT), pulmonary function tests including diffusing capacity, blood tests for autoimmune markers, and a careful review of exposures. When indicated, the diagnosis is reached through a multidisciplinary discussion (MDD) with thoracic radiologists, rheumatologists and pathologists. Bronchoscopy with BAL or a biopsy is sometimes needed.
If needed, spirometry can also be performed at the clinic during the visit.
When to start treatment
Not every case of fibrosis requires antifibrotic treatment right away. In idiopathic pulmonary fibrosis (IPF), treatment is usually recommended from the time of diagnosis. In other interstitial diseases, patients are followed closely, and antifibrotic treatment is added when the disease progresses. This is called progressive pulmonary fibrosis (PPF), defined as at least two of the following three within the past year, with no other explanation: worsening symptoms, declining lung function, and progression on CT. Regular follow-up is therefore a central part of care.
Treatment
In IPF and progressive pulmonary fibrosis there are antifibrotic treatments that slow the rate of decline in lung function: nintedanib (Ofev), pirfenidone (Esbriet, approved for IPF) and nerandomilast (Jascayd), a new treatment from the PDE4B inhibitor class, approved in the United States and Europe for both IPF and PPF. In inflammatory diseases, treatments that modulate the immune system are used. Alongside these: pulmonary rehabilitation, oxygen as needed, vaccinations and, in suitable cases, referral for lung transplant evaluation.
Encouraging advances
This is a fast-moving field. Nerandomilast, from a new drug class, has recently joined the approved treatments, and additional drugs are in late-stage development. Among them is inhaled treprostinil (Tyvaso), which slowed lung function decline in IPF in two phase 3 trials (TETON-1 and TETON-2) and is now under FDA review. At the same time, diagnostic and monitoring tools are improving, including computer-based analysis of CT scans.
Sarcoidosis
Sarcoidosis is an inflammatory disease that most often affects the lungs and the lymph nodes in the chest, and appears mainly between the ages of 20 and 50. More on the sarcoidosis page.
Frequently asked questions
Does fibrosis always get worse?
Not necessarily. The pace varies between diseases and between individuals. Regular follow-up with lung function tests and imaging allows treatment to be adjusted in time.
Related topics
General information only; it does not replace a medical consultation. עברית