Drug-induced interstitial lung disease, or DI-ILD, is a significant health concern that affects many individuals worldwide. This condition occurs when certain medications cause inflammation and scarring (fibrosis) of the lung tissue, leading to breathing difficulties and other serious respiratory issues. Raising awareness and understanding of DI-ILD is crucial for early detection, proper management, and support for affected individuals and their families.
What is Drug-Induced ILD?
Drug-induced interstitial lung disease is a subset of interstitial lung diseases (ILDs), a group of disorders characterised by inflammation and scarring of the lung’s interstitium, the tissue surrounding the air sacs. In drug-induced ILD, the lung damage is specifically caused by adverse reactions to certain medications. These reactions can vary from mild inflammation to severe fibrosis, significantly impairing lung function.
Common Causes
Although the majority of patients will not be affected, several types of drugs are known to potentially cause DI-ILD, including:
- Chemotherapy Agents: Medications used to treat cancer, such as bleomycin and some of the newer check point inhibitors, can cause lung toxicity.
- Antibiotics: Some antibiotics, like nitrofurantoin, have been linked to DI-ILD.
- Anti-inflammatory Drugs: Non-steroidal anti-inflammatory drugs (NSAIDs) and certain biologics used for autoimmune conditions can also induce lung disease.
- Cardiovascular Drugs: Medications like amiodarone, used to treat heart arrhythmias, are known culprits.
Symptoms and Diagnosis
The symptoms of drug-induced interstitial lung disease can be non-specific and similar to other respiratory conditions, making diagnosis challenging. Common symptoms include:
- Persistent cough.
- Shortness of breath, especially with exertion.
- Fatigue.
- Chest discomfort.
To diagnose DI-ILD, healthcare providers typically perform a combination of the following:
- Medical History and Medication Review: Assessing the patient’s medication history to identify potential causative agents.
- Imaging Tests: High-resolution CT scans of the chest can reveal patterns of lung inflammation and scarring.
- Lung Function Tests: Pulmonary function tests (PFTs) measure the extent of lung impairment.
- Biopsy: In some cases, a lung biopsy may be necessary to confirm the diagnosis.
Treatment and Management
The primary approach to managing drug-induced ILD is discontinuing the offending drug. Additional treatments may include:
- Corticosteroids: These anti-inflammatory medications can help reduce lung inflammation.
- Immunosuppressive Drugs: In some cases, drugs that suppress the immune system may be used to control severe inflammation.
- Oxygen Therapy: For patients with significant breathing difficulties, supplemental oxygen can help improve oxygen levels in the blood.
- Pulmonary Rehabilitation: A structured program of exercise and education can help improve lung function and quality of life.
Research into Drug-Induced Interstitial Lung Disease
There is very little research in the area of DI-ILD, mainly because it may be missed or diagnosed as another condition. We are bringing together a group of ILD clinicians in the UK and Europe to further understand the diagnosis and management of these diseases with specific research aimed at
- Identifying better diagnostic tools and criteria;
- Novel biomarkers for diagnosis and treatment response including blood-based biomarkers and imaging biomarkers;
- An understanding of the risk factors for developing DI-ILD and so identify those patients most at risk; and
- The most appropriate treatment approaches.
There is a lot of work to do, but we have never been in such a good position to do it and help all those patients with iatrogenic medication induced lung disease.
Conclusion
Drug-induced interstitial lung disease is a serious, but often under-recognised condition. By increasing awareness, supporting research and providing resources to affected individuals, we can make a meaningful difference in the lives of those impacted by DI-ILD. Together, we can work towards a future where every patient receives timely diagnosis, effective treatment and comprehensive support.