What is pulmonary fibrosis?

From the Guidelines

Pulmonary fibrosis is a chronic lung disease characterized by the progressive scarring of lung tissue, which leads to breathing difficulties, and its management should be guided by the most recent clinical practice guidelines, such as those from the American Thoracic Society, European Respiratory Society, Japanese Respiratory Society, and Asociacion Latinoamericana de Torax 1. The scarring (fibrosis) causes the lungs to become stiff and thick, making it increasingly difficult for oxygen to pass from the air sacs into the bloodstream. This condition typically develops gradually, with symptoms including:

• Shortness of breath
• A persistent dry cough
• Fatigue
• Unexplained weight loss
• Aching muscles and joints The most common form is idiopathic pulmonary fibrosis, meaning the cause is unknown, though risk factors include smoking, certain environmental exposures, viral infections, and genetic predisposition, as highlighted in recent studies 1. Treatment options should focus on slowing disease progression, improving symptoms, and enhancing quality of life, with medications like pirfenidone and nintedanib being considered based on the latest evidence-based recommendations 1. Additionally, oxygen therapy, pulmonary rehabilitation, and in severe cases, lung transplantation may be considered. The disease damages the delicate balance between normal healing and excessive scarring, as the body attempts to repair damaged lung tissue but produces too much collagen and other proteins, leading to the characteristic scarring that impairs lung function over time. Key aspects of managing pulmonary fibrosis include:
• Accurate diagnosis using radiological and histopathological criteria
• Assessment of disease progression and response to treatment
• Patient-centered care, including education, support, and symptom management
• Consideration of genetic testing for familial pulmonary fibrosis, as recommended by the Pulmonary Fibrosis Foundation Genetic Testing Work Group 1

From the FDA Drug Label

Pirfenidone is a prescription medicine used to treat people with a lung disease called idiopathic pulmonary fibrosis (IPF).

Pulmonary fibrosis, specifically idiopathic pulmonary fibrosis (IPF), is a lung disease treated by pirfenidone.

• It is a condition where the lungs become scarred, leading to breathing difficulties.
• The exact cause of IPF is unknown, but pirfenidone is used to treat it.
• Key points about pulmonary fibrosis include:
  • Scarring of the lungs
  • Breathing difficulties
  • Unknown cause (in the case of IPF)
  • Treated with pirfenidone 2

From the Research

Definition and Overview of Pulmonary Fibrosis

• Pulmonary fibrosis is a chronic progressive lung disease that leads to lung architecture disruption and respiratory failure 3.
• It is characterized by the formation of scar tissue within the lungs in the absence of any known provocation 4.
• The disease can be idiopathic, meaning of unknown cause, or associated with various factors such as environmental exposures or connective tissue diseases.

Causes and Risk Factors

• The development of pulmonary fibrosis is mostly the result of previous acute lung inflammation, caused by a wide variety of etiological factors, not resolved over time and causing the deposition of fibrotic tissue in the lungs 3.
• Environmental factors such as cigarette smoking, exposure to silica, and livestock may be associated with idiopathic pulmonary fibrosis (IPF) 4.
• IPF is recognized on high-resolution computed tomography by peripheral, subpleural lower lobe reticular opacities in association with subpleural honeycomb changes 4.

Symptoms and Diagnosis

• IPF initially manifests with symptoms of exercise-induced breathlessness and dry coughing 4.
• Auscultation of the lungs reveals early inspiratory crackles, predominantly located in the lower posterior lung zones upon physical exam 4.
• Clubbing is found in approximately 50% of IPF patients, and cor pulmonale develops in association with end-stage disease 4.
• The diagnosis of IPF requires correlation of the clinical setting with radiographic images and a lung biopsy, or defined clinical criteria in the absence of lung biopsy 4.

Treatment and Management

• Medical therapy has been ineffective in the treatment of IPF in the past, but new molecular therapeutic targets have been identified and several clinical trials are investigating the efficacy of novel medications 4.
• Antifibrotic agents such as pirfenidone and nintedanib have been shown to slow disease progression and improve lung function in some cases 5, 6.
• Nintedanib is effective in slowing IPF progression and reducing the annual rate of decline in forced vital capacity (FVC) among patients with progressive pulmonary fibrosis (PPF) compared to placebos 7.
• Nonpharmacological treatment, including pulmonary rehabilitation, supplemental oxygen therapy, and vaccination, also play important roles in the management of PPF, leading to comprehensive care for patients with interstitial lung disease (ILD) 7.