From the Guidelines
Interstitial lung disease (ILD) is a diverse group of disorders characterized by inflammation and scarring in the lungs, leading to irreversible lung damage, morbidity, and increased mortality, as highlighted in a recent study 1. In simple terms, ILD is when the delicate lung tissue becomes damaged, thickened, and stiff over time, making it harder for oxygen to pass from the air sacs into the bloodstream, resulting in breathing difficulties and decreased oxygen levels in the body. The causes of ILD can vary, including:
- Exposure to environmental toxins like asbestos or silica dust
- Certain medications
- Radiation therapy
- Autoimmune diseases like rheumatoid arthritis
- Sometimes without any known cause (idiopathic) Common symptoms of ILD include:
- Shortness of breath, especially during physical activity
- Dry cough
- Fatigue
- Gradual weight loss As noted in a 2024 guideline by the American College of Rheumatology 2, ILD is a significant cause of morbidity and mortality in people with systemic autoimmune rheumatic diseases, and early diagnosis and treatment are crucial to help preserve lung function and quality of life. The scarring that occurs in ILD is usually permanent and often progressive, meaning it worsens over time, emphasizing the need for prompt medical attention and treatment to slow disease progression 1. Treatment for ILD typically focuses on slowing disease progression and may include:
- Medications like corticosteroids or immunosuppressants to reduce inflammation
- Oxygen therapy to improve oxygen levels
- Pulmonary rehabilitation to improve breathing capacity
- In severe cases, lung transplantation may be considered It is essential to maintain a high level of suspicion for ILD, as early but irreversible lung function loss can occur asymptomatically, and prompt recognition can help stabilize or slow irreversible lung function loss immediately 1.
From the Research
Definition of Interstitial Lung Disease
Interstitial lung disease (ILD) refers to a group of pulmonary disorders characterized by inflammation and/or fibrosis of the lung parenchyma, associated with progressive dyspnea that frequently results in end-stage respiratory failure 3.
Characteristics of Interstitial Lung Disease
- ILD consists of over 200 different diseases, ranging from rare to relatively common 4
- The most common forms of ILD are idiopathic pulmonary fibrosis (IPF), hypersensitivity pneumonitis, and connective tissue disease (CTD) 3
- ILD typically presents with dyspnea on exertion and can progress to respiratory failure 3, 5
- Approximately 30% of patients with ILD report cough 3
Diagnosis and Management of Interstitial Lung Disease
- A multidisciplinary approach to diagnosis of ILD is the gold standard, including key history and examination features, blood panel, pulmonary function tests, high resolution computed tomography imaging, and when required bronchoalveolar lavage and lung biopsy results 5
- Antifibrotic therapy with nintedanib or pirfenidone slows annual FVC decline by approximately 44% to 57% in individuals with IPF, scleroderma associated ILD, and in those with progressive pulmonary fibrosis of any cause 3
- Immunomodulatory therapy, such as tocilizumab, rituximab, and mycophenolate mofetil, may slow decline or even improve FVC at 12-month follow-up in patients with connective tissue disease-associated ILD 3
- Pulmonary rehabilitation probably improves functional exercise capacity, dyspnea, and quality of life in the short term, with benefits also probable in IPF 6
Treatment Options for Interstitial Lung Disease
- First-line therapy includes nintedanib or pirfenidone for IPF and mycophenolate mofetil for ILD due to connective tissue disease 3
- Lung transplant should be considered for patients with advanced ILD 3
- Corticosteroids are widely used in the treatment of acute exacerbation of ILD (AE-ILD), and higher doses (> 1 mg/kg prednisolone) may improve outcomes in patients with AE-non-IPF-ILD 7