Interstitial lung disease (ILD) is a broad term for a group of conditions that cause progressive scarring and inflammation of the lung tissue. Left untreated, ILD can permanently impair lung function and lead to respiratory failure. Early diagnosis and specialist management are critical to slowing disease progression and maintaining quality of life.
At RSDC Melbourne, our respiratory physicians provide comprehensive assessment and ongoing management for patients with interstitial lung disease across five clinic locations.
What Is Interstitial Lung Disease?
The interstitium is the network of tissue that surrounds and supports the air sacs (alveoli) of the lungs. In ILD, this tissue becomes inflamed and over time may scar and thicken — a process called fibrosis. As fibrosis progresses, the lungs become stiffer and less efficient at transferring oxygen into the bloodstream.
ILD is not a single disease but an umbrella term covering more than 200 distinct conditions. The most clinically significant include:
- Idiopathic Pulmonary Fibrosis (IPF) — the most common and most severe form of ILD, with unknown cause and progressive fibrosis. IPF carries a poor prognosis without treatment.
- Hypersensitivity Pneumonitis (HP) — an immune reaction to inhaled organic dusts, mould, or bird proteins (e.g. bird fancier’s lung, farmer’s lung)
- Non-Specific Interstitial Pneumonia (NSIP) — often associated with connective tissue diseases (rheumatoid arthritis, scleroderma, Sjogren’s syndrome)
- Sarcoidosis — a multisystem inflammatory disease that commonly affects the lungs and lymph nodes
- Cryptogenic Organising Pneumonia (COP) — a pattern of lung inflammation that may follow infection, drug exposure, or occur without a clear cause
- Drug-induced ILD — certain medications including methotrexate, amiodarone, nitrofurantoin, and checkpoint inhibitors can cause ILD
- Occupational ILD — including silicosis, asbestosis, and coal workers’ pneumoconiosis
Symptoms of Interstitial Lung Disease
ILD symptoms can develop gradually over months or years, and are frequently attributed to other conditions or the normal effects of ageing. Key symptoms to watch for include:
- Progressive breathlessness — initially on exertion, worsening over time until it occurs at rest
- Dry, persistent cough — often non-productive (no mucus), and frequently dismissed as a minor complaint
- Fatigue and reduced exercise tolerance
- Finger clubbing — rounding and enlargement of the fingertips, seen in some forms of ILD including IPF
- Chest discomfort
- Low oxygen saturation — particularly during physical activity
If you experience persistent unexplained breathlessness or cough, it is important to seek assessment promptly. ILD is progressive — early intervention preserves more lung function.
How Is Interstitial Lung Disease Diagnosed?
Diagnosing ILD requires a combination of clinical assessment, imaging, and lung function testing. At RSDC, our respiratory physicians coordinate a comprehensive diagnostic pathway:
High-Resolution CT (HRCT) of the chest — the most important diagnostic tool for ILD. HRCT identifies the pattern and distribution of lung changes, guiding the diagnosis without the need for biopsy in many cases.
Lung function testing (RFT) — ILD typically produces a restrictive pattern: reduced total lung capacity and FVC, with a reduced or normal FEV1/FVC ratio. Diffusing capacity (DLCO/TLCO) is usually impaired, reflecting reduced gas transfer.
Six-minute walk test — assesses functional exercise capacity and oxygen saturation on exertion, used to stage severity and monitor progression.
Blood tests — including autoimmune antibody panels (ANA, anti-CCP, anti-Scl-70), inflammatory markers, and specific antigen testing for hypersensitivity pneumonitis.
Bronchoscopy with bronchoalveolar lavage (BAL) — may be performed to obtain cells from the lower airways. RSDC offers bronchoscopy at Knox Private Hospital.
Surgical lung biopsy or cryobiopsy — occasionally required for definitive diagnosis when imaging and clinical findings are inconclusive.
Treatment of Interstitial Lung Disease
Treatment depends on the specific type of ILD, severity, rate of progression, and underlying cause. Key treatment approaches include:
Antifibrotic therapy (IPF) — nintedanib (Ofev) and pirfenidone (Esbriet) are PBS-subsidised in Australia for IPF. These medications slow the rate of fibrosis progression and reduce acute exacerbations, though they do not reverse existing damage.
Corticosteroids and immunosuppressants — used in inflammatory ILDs such as NSIP, COP, hypersensitivity pneumonitis, and connective tissue disease-associated ILD. Prednisone, mycophenolate, and azathioprine are commonly used.
Removal of the causative agent — in hypersensitivity pneumonitis, identifying and eliminating exposure to the offending antigen (mould, bird proteins, certain dusts) is the most important intervention.
Pulmonary rehabilitation — structured exercise and breathing training improves breathlessness and exercise tolerance in patients with ILD.
Supplemental oxygen — prescribed for patients with significant hypoxaemia at rest or on exertion.
Lung transplantation — considered in eligible patients with end-stage ILD, particularly IPF, where other treatment options have been exhausted.
Vaccinations — annual influenza and pneumococcal vaccines are recommended to reduce the risk of respiratory infections, which can trigger acute ILD exacerbations.
Interstitial Lung Disease Care at RSDC Melbourne
Our RSDC respiratory physicians provide specialist ILD assessment and ongoing management, including:
- Comprehensive lung function testing and DLCO measurement on-site
- Coordination of CT chest imaging and specialist reporting
- Autoimmune and occupational exposure assessment
- Initiation and monitoring of antifibrotic and immunosuppressant therapy
- Pulmonary rehabilitation referral
- Oxygen assessment and prescription
- Multidisciplinary coordination with rheumatologists, radiologists, and thoracic surgeons where needed
When to See a Respiratory Specialist for ILD
You should seek urgent specialist assessment if you have:
- New or worsening unexplained breathlessness
- CT findings consistent with ILD reported by a radiologist
- A connective tissue disease (rheumatoid arthritis, scleroderma, myositis) and new respiratory symptoms
- Occupational exposure history (silica, asbestos, birds, mould) with respiratory symptoms
- A known ILD diagnosis requiring review or treatment adjustment
RSDC has five Melbourne clinic locations: Camberwell, Richmond, Knox, Ferntree Gully, and Balwyn North. A GP referral is required. Contact us today to arrange your interstitial lung disease assessment in Melbourne.
Related articles:
Diagnosis of interstitial lung disease requires comprehensive lung function testing — including spirometry and DLCO measurement — available at all RSDC locations. In some cases, bronchoscopy may be required to obtain a tissue sample for diagnosis.
To understand the difference between obstructive and restrictive lung disease patterns, see our guide to obstructive vs restrictive lung disease.
