ILD refers to scarring (fibrosis) of lung tissue. As fibrosis progresses, the lungs become stiffer and less efficient in oxygen exchange, leading to breathlessness, reduced exercise tolerance, and, in advanced stages, respiratory failure.

In ANCA-positive individuals, ILD may occur in two settings:

AAV-ILD: ILD as part of ANCA-associated vasculitis (such as microscopic polyangiitis or granulomatosis with polyangiitis), where other organs may also be affected.

ANCA-ILD: ILD in patients with positive ANCA antibodies but without clear systemic vasculitis.

The study found that most patients were MPO-ANCA positive, and the most common CT pattern was UIP (Usual Interstitial Pneumonia), which is generally associated with a poorer prognosis.

Across the full cohort of 162 patients, during approximately four years of follow-up:

• 19% developed long-term oxygen dependence;
• 48% died.

Importantly, the strongest predictors of poor outcome were related to the lungs themselves:

• lower lung function (FVC) at diagnosis;
• greater extent of fibrosis on the initial CT scan;
• older age at diagnosis.

Although kidney involvement was common, it did not independently predict mortality. This suggests that lung disease severity at baseline may be the main driver of long-term outcomes in this population.

Rituximab showed a trend toward stabilising or improving lung function, particularly in patients with the UIP pattern. However, antifibrotic treatments were rarely used, and their role in ANCA-associated ILD remains unclear.

Why Specialist Care Is Essential

One of the key messages emerging from this study is that patients with ANCA-associated ILD should ideally be managed by a multidisciplinary team.

This means access not only to physicians experienced in ANCA-associated vasculitis, but also to respiratory physicians (pulmonologists) with specific expertise in interstitial lung disease. ILD is a complex and rapidly evolving field, and accurate interpretation of CT patterns, lung function trends, and treatment options requires specialist knowledge. For a condition that carries a serious prognosis, patients deserve advice from professionals who are both well-informed and experienced in this specific overlap between vasculitis and lung fibrosis.

Why This Matters for Patient Organisations

These findings reinforce several important advocacy priorities:

• Early lung assessment (including CT imaging and lung function testing) at diagnosis.
• Structured, long-term monitoring of respiratory function.
• Access to multidisciplinary care involving both vasculitis specialists and ILD-experienced pulmonologists.
• Greater research investment into targeted and antifibrotic therapies.

For patient organisations, this study provides strong evidence to support awareness of lung involvement in ANCA-related disease and to advocate for earlier recognition, specialist referral, and personalised care strategies.

For patients, it underlines an important practical message: if ILD is suspected or confirmed, seek care in centres where both vasculitis expertise and ILD expertise are available.

Reference
Chalkia A et al. Interstitial Lung Disease in ANCA-Associated Vasculitis:
A European Multicentre Study. Arthritis & Rheumatology. DOI: 10.1002/art.70078.