What is Connective Tissue Disease-Associated Interstitial Lung Disease (CTD-ILD)?
CTD-ILD is inflammation and scarring of the lung tissue occurring as part of an autoimmune disease — most often systemic sclerosis, myositis, rheumatoid arthritis or Sjögren's syndrome. It usually begins with a dry cough or breathlessness on exertion, and it is far more treatable when detected by screening than when it presents with symptoms.
Also called: CTD-ILD, autoimmune lung fibrosis
Who gets Connective Tissue Disease-Associated Interstitial Lung Disease (CTD-ILD)?
It is commonest in systemic sclerosis, where a majority have some lung involvement on CT, and in antisynthetase syndrome and other forms of myositis. It also occurs in rheumatoid arthritis, Sjögren's syndrome and mixed connective tissue disease. Certain antibodies — anti-Scl-70, anti-Jo-1 and other antisynthetase antibodies, anti-MDA5 — mark a substantially higher risk.
What are the symptoms of Connective Tissue Disease-Associated Interstitial Lung Disease (CTD-ILD)?
Not everyone has every symptom below, and having one does not confirm the diagnosis. These are the features that most often lead to assessment:
- A persistent dry cough with no infection
- Breathlessness on exertion — climbing stairs, walking uphill — that has progressed over months
- Reduced exercise tolerance
- Fatigue
- Fine crackles at the lung bases, heard on examination
- Clubbing of the fingertips in some patients
- Often completely silent in the early stages
How is Connective Tissue Disease-Associated Interstitial Lung Disease (CTD-ILD) diagnosed?
High-resolution CT of the chest is the definitive imaging test and shows both the extent and the pattern of disease, which affects treatment and prognosis.
Lung function testing measures forced vital capacity and gas transfer, and these numbers are what treatment is monitored against over time.
A six-minute walk test with oxygen saturation adds functional information.
Antibody testing identifies the underlying disease and the specific risk. Echocardiography screens for pulmonary hypertension, which can coexist and needs different treatment. Infection and drug causes are excluded.
How is Connective Tissue Disease-Associated Interstitial Lung Disease (CTD-ILD) treated?
Treatment depends on the underlying disease and how much of the lung is affected.
Mycophenolate is the usual first-line immunosuppressant, with cyclophosphamide reserved for rapidly progressive disease. Rituximab and tocilizumab are used in selected patients.
Antifibrotic therapy — nintedanib — slows the decline in lung function in progressive fibrosing disease and can be combined with immunosuppression.
Supportive care matters as much as the drugs: pulmonary rehabilitation, vaccination against influenza and pneumococcus, treatment of reflux (which worsens fibrosis, particularly in scleroderma), oxygen where needed, and complete avoidance of smoking.
Living with Connective Tissue Disease-Associated Interstitial Lung Disease (CTD-ILD)
Lung function is tracked every three to twelve months depending on activity, and treatment decisions are made on trends rather than single results. Many patients stabilise on treatment. Reflux control is genuinely important in scleroderma-related disease because aspiration contributes to progression. Any sudden worsening of breathlessness needs urgent assessment to exclude infection, clot or pulmonary hypertension.
When should you see a rheumatologist?
A dry cough or breathlessness that has developed over weeks to months in anyone with an autoimmune disease, or alongside Raynaud's, rashes or muscle weakness, should be assessed with lung function tests and a CT scan.
Common questions about Connective Tissue Disease-Associated Interstitial Lung Disease (CTD-ILD)
Is lung fibrosis reversible?
Inflammation can improve with treatment; established scarring cannot be reversed. This is why early detection through screening — before symptoms appear — makes such a difference to long-term lung function.
Why do I need lung tests if I am not breathless?
Because early interstitial lung disease is silent. In systemic sclerosis and myositis, routine screening finds treatable disease at a stage where lung function can still be preserved.
Does treating reflux really help my lungs?
In scleroderma-associated lung disease, yes. Silent aspiration of refluxed material contributes to fibrosis, so proton pump inhibitors, meal timing and elevating the head of the bed are part of lung care.
This page is general information to support a consultation. It is not a diagnosis, and it does not replace an assessment by a doctor who has examined you.