What is diffuse interstitial lung disease, and which are the symptoms and the diagnostic procedure as one of the most common extra-articular manifestation of rheumatoid arthritis?

Diffuse interstitial lung disease is a potentially severe complication of rheumatoid arthritis, affecting up to 10% of rheumatoid arthritis patients and contributing significantly to morbidity and mortality. Diffuse interstitial lung disease in rheumatoid arthritis typically involves inflammation and fibrosis of lung tissue, which can impair lung function and lead to respiratory failure.

The symptoms of diffuse interstitial lung disease in patients with rheumatoid arthritis can vary widely, but commonly include:

  • Shortness of breath (dyspnea): Often the first and most prominent symptom, dyspnea typically worsens over time, especially with exertion.
  • Chronic dry cough: Persistent, non-productive cough is another frequent complaint in diffuse interstitial lung disease, often exacerbating discomfort and impacting quality of life.
  • Fatigue and weakness: Respiratory insufficiency can lead to fatigue, a common but non-specific symptom.
  • Chest discomfort: Some patients may experience a vague chest tightness or discomfort, particularly during physical activity.
  • Crackles on lung examination: Fine "Velcro-like" crackles, often heard at the lung bases during auscultation, are a common finding in diffuse interstitial lung disease.

Symptoms may be subtle in early disease, which is why regular screening in rheumatoid arthritis patients is crucial for timely diagnosis and intervention.

Early detection of diffuse interstitial lung disease in rheumatoid arthritis patients is critical to prevent progression and irreversible lung damage.

Pulmonary function tests are valuable in detecting early lung involvement and are often recommended periodically for rheumatoid arthritis patients. A reduction in forced vital capacity and diffusion capacity for carbon monoxide can be early indicators of diffuse interstitial lung disease .

High-Resolution Computed Tomography is more sensitive than X-rays and can detect interstitial changes at earlier stages. it is the gold standard for imaging in suspected diffuse interstitial lung disease and allows for the evaluation of lung patterns, such as ground-glass opacities, honeycombing, or reticulation.

Due to the potential subtle onset, rheumatoid arthritis patients should be routinely monitored for respiratory symptoms, especially those with longstanding or severe rheumatoid arthritis.