Interstitial Lung Disease (ILD): Causes, Diagnosis, Treatment, and Management

What is interstitial lung disease

Interstitial lung disease (ILD) is a term used to describe a large group of diseases that cause scarring of the lungs. This scarring makes the lungs stiff, making it difficult for oxygen to enter into the blood. As a result, it becomes hard to breathe.1 There are about 200 different types of ILD. The lung damage from ILD usually gets worse over time and can't be reversed, leading to breathing problems and a reduction in lung function.² However, if some ILDs are detected early and treated appropriately, they can sometimes be improved or even reversed.

What happens in ILD?

In ILD, the lungs become inflamed and/ scarred due to injury .^{3, 4}.
This means:

The lungs get irritated, leading to more damage and scarring.

The lungs don't work properly, making it harder to breathe and can cause symptoms like shortness of breath and a dry cough.

The lung tissue thickens, making it harder for oxygen to get into the blood.

Performing regular physical activities becomes difficult.^3,4

Who is at risk of developing ILD?

Irrespective of age, anyone can develop ILD, including children. Factors that increase the risk include family history of ILD, certain treatments like radiation or chemotherapy, and exposure to harmful substances . People with conditions where the immune system mistakenly attacks the body parts, such as rheumatoid arthritis (joints are affected), are also at higher risk of developing ILD.¹

Different types of ILD

Idiopathic Pulmonary Fibrosis (IPF):
This type of ILD causes scarring of the lungs from an unknown cause and has a poor long-term prognosis. Symptoms include gradually worsening of shortness of breath and a dry cough.⁵

Sarcoidosis:
This disease causes inflamed tissues (called granulomas) to develop in various organs, including lungs, leading to inflammation and scarring.^6,7

Connective Tissue Disease-related ILD:
This type of ILD is linked to connective tissue diseases and causes lung inflammation or scarring.

Exposure ILD:
This type is caused by exposure to harmful substances at work, like asbestos, coal or silica dust. Some individuals who get exposed to bird droppings or come in contact with birds/pigeons are at risk of hypersensitivity Pneumonitis ( sub type of exposure ILD),^8,9,10

Drug-induced ILD:
Certain medications such as heart medications, and chemotherapy drugs can cause ILD, leading to a range of symptoms from mild to severe.¹¹

Smoking- induced ILD:
Lifestyle habits, such as smoking, can lead to the development and worsening of ILD by causing inflammation and scarring in the lungs, ultimately making lung damage worse.¹⁰

Managing and understanding ILD involves recognizing these risks and working with healthcare providers to manage symptoms and improve quality of life.¹⁰

ILD diagnosis and tests

Diagnosing ILD can be tricky because its symptoms are similar to many other health problems. To determine if you have ILD, your doctor will take a detailed medical history and perform a physical examination. They will listen for unusual lung sounds and check for signs such as clubbed fingers. Your doctor may order some of the following tests to confirm the diagnosis:

Common tests for diagnosing ILD

Blood Tests:
These tests look for markers of autoimmune diseases or reactions to environmental exposures like molds or bird proteins.

Imaging Tests:
Lung tests such as Chest X-rays and HRCT Scans take pictures of your lungs to help doctors see if there's any inflammation or scarring in your lungs.

Pulmonary Function Tests (PFTs):
PFTs helps measure how well your lungs are working by seeing how much air they can hold and how well oxygen is transferred into your blood.¹⁰

However, in some cases, when your diagnosis is not established from the above tests, your doctor will suggest Lung Biopsy to confirm the diagnosis.¹

ILD treatment

Your treatment for ILDs will depend on the cause and severity of your condition. Your doctor will work with you to create a personalized treatment plan. While ILD treatments are given with a goal to help prevent further damage and make breathing easier in some cases treatment alongwith avoiding exposure that caused ILD can reverse the disease when treated early .

Medications

Depending on the type of ILD you have, your doctor may prescribe following medicine to help control your disease from getting worse:

Steroids:
These medicines help reduce inflammation in your lungs. They can be taken as a pill.

Antifibrotics:
These medicines slow down lung damage by blocking certain growth factors that cause lung scarring. You may need to take these pills daily.¹⁰

Immunosuppressant:
These medications are sometimes used alongsidewith steroid medications in the treatment of ILD to help manage inflammation and prevent further lung damage.¹²

In addition to above medicines, you may be advised following supportive therapy:

Oxygen Therapy:
While oxygen therapy doesn't stop lung damage, it can be beneficial in several ways. It makes breathing easier, reduces complications from low oxygen levels, and improves your sleep and overall well-being.

Pulmonary Rehabilitation:
Pulmonary rehabilitation is a program designed to help you live better with ILD. It includes physical exercise, breathing techniques to help your lungs work more efficiently and to improve yourstamina. , including emotional support to help you cope with the disease, and nutritional counselling to ensure you're eating well and getting the nutrients you need.

In addition to above medicines, you may be advised to follow supportive therapy:

Prevention of ILD symptoms

If you have an ILD, your doctor may ask you to take the following steps to help manage the condition and avoid complications.

Stop Smoking:
Smoking can further damage your lungs & worsen your disease

Eat Well:
Eating a balanced diet is important, especially when you have ILD, as the disease can make it hard to maintain a healthy weight. Your doctor will recommend nutritious foods that provide enough energy and support your overall health. It is important to include vegetables, fruits, whole grains and especially protein in your diet, as it helps build muscles and strengthens your immune system, which is vital for managing ILD.¹⁴

Avoid Triggers:
If you know certain substances or environments worsen your condition, try to avoid them. This might include reducing exposure to dust, chemicals, or other irritants.

Stay Active:
Engaging in light physical activity can help keep you strong and improve your overall well-being. However, always check with your doctor about what type of exercise is safe for you. ^1,10,14

How well can ILD be managed?

Tracking Your Symptoms :
Your symptoms may change over time. Your doctor will use various tests to monitor your condition. Let your doctor know about any changes in how you feel. This helps them understand if your illness is getting worse and guides them in adjusting your treatment.¹⁵

Monitor Your Symptoms:
Keeping track of your symptoms can be helpful. Write down any new symptoms or changes you notice and inform to your doctor to get the best care.

Keep an eye on any worsening symptoms, such as

Difficulty breathing, even with light activity

Feeling unusually tired or unwell

Rapid breathing ³

A persistent cough that doesn’t go away

Sudden weight loss

Psychological support

It is important to get mental and emotional support to stay positive during ILD treatment. Therefore, keeping in touch with friends, family, or support groups can be helpful. They can offer support and make it easier to cope with living with ILD.¹⁰

Self-Management and patient education

Learning how to manage your symptoms, treatment, and lifestyle changes can be helpful during ILD treatment. Patient education helps you learn how to manage your condition effectively. Understanding your illness and its treatment helps you stay committed to exercise, lifestyle changes, and taking your medication, which can improve your health over time. Educational programs also give you useful information about managing long-term health conditions. It helps you handle your illness better, boosts your confidence, and makes it easier to stick to your treatment plan.^16,17

Reference

American Lung Association. Interstitial Lung Disease (ILD) | American Lung Association [Internet]. www.lung.org. Available from: Click here
Althobiani MA, Russell AM, Jacob J, Ranjan Y, Folarin AA, Hurst JR, et al. Interstitial lung disease: a review of classification, etiology, epidemiology, clinical diagnosis, pharmacological and non-pharmacological treatment. Frontiers in medicine. 2024 Apr 18;11.
Mendes RG, Castello-Simões V, Trimer R, Garcia-Araújo AS, Gonçalves Da Silva AL, Dixit S, et al. Exercise-Based Pulmonary Rehabilitation for Interstitial Lung Diseases: A Review of Components, Prescription, Efficacy, and Safety. Frontiers in Rehabilitation Sciences. 2021 Nov 16;2.
Lung scarring symptoms and causes. Human Biology. [Internet]. 2024. Available from: Click here
Sankari A, Chapman K, Ullah S. Idiopathic Pulmonary Fibrosis. StatPearls [Internet]. 2024 Jan.
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What are the different types of ILD? [Internet]. Interstitial Lung Disease (ILD) Patient Education. [cited 2024 Jul 25]. Available from: Click here
Wu H, Sears LE, Coberley CR, Pope JE. Overall Well-Being and Supervisor Ratings of Employee Performance, Accountability, Customer Service, Innovation, Prosocial Behavior, and Self-Development. Journal of Occupational and Environmental Medicine. 2015 Nov;1.
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Interstitial lung diseases. NIH. [Internet]. 2024. Available from: Click here
Spagnolo P, Bonniaud P, Rossi G, Sverzellati N, Cottin V. Drug-induced interstitial lung disease. European Respiratory Journal. 2022 Mar 24;2102776.
Comprehensive ILD Treatment Options. NationalJewishHealth. [Internet]. 2024. Available from: Click here
Interstitial lung diseases. Mayoclinic. [Internet]. 2024. Available from: Click here
Living with Interstitial lung diseases. [Internet]. 2024. Available from: Click here
Monitoring Symptoms of ILD. Lungs&You. [Internet]. 2024. Available from: Click here
Lee JY, Tikellis G, Dowman L, Jones AW, Hoffman M, Mellerick CR, Malaguti C, Khor YH, Holland AE. Self-management interventions for people with pulmonary fibrosis: a scoping review. European Respiratory Review. 2023 Dec 31;32(170).
Amin R, Vaishali K, Maiya GA, Mohapatra AK, Sinha MK, Bhat A, Bommasamudram T, Acharya V, Gore S. Patient education for individuals with Interstitial Lung Disease: A scoping review. F1000Research. 2024;13.