Interstitial lung disease

Overview  

Interstitial lung disease, also known as diffuse parenchymal lung disease (DPLD), encompasses a wide range of conditions, the majority of which lead to the gradual formation of scar tissue in the lungs. This scarring ultimately hampers one’s ability to breathe and impedes the intake of sufficient oxygen into the bloodstream. 

Long–term exposure to harmful substances, such as asbestos, can be a catalyst for interstitial lung disease. Additionally, certain autoimmune disorders like rheumatoid arthritis may contribute to the development of this condition. Nevertheless, in some instances, the exact causes remain elusive. 

It is important to note that once lung scarring occurs, it is typically irreversible. While medications can help slow down the progression of interstitial lung disease, many individuals may never fully regain their lung function. For select individuals with this condition, a lung transplant may be considered as a potential treatment option. 

Symptoms  

Interstitial lung disease typically presents with the following common symptoms: 

• Shortness of breath, whether it occurs during rest or is exacerbated by physical exertion. 
• A persistent, dry cough. 
• Fatigue. 
• Chest discomfort. 

It’s important to be aware that when these symptoms become noticeable, irreversible lung damage may have already occurred. Therefore, seeking prompt medical attention when initial breathing difficulties arise is essential. Numerous respiratory ailments besides interstitial lung disease have the potential to impact the lungs, emphasizing the critical need to secure an early and precise diagnosis to facilitate effective treatment. 

Causes  

Interstitial lung disease occurs when lung injury triggers an abnormal healing response, leading to scarring and thickening of the tissue around air sacs (alveoli), making it harder for oxygen to enter the bloodstream. Causes include: 

• Occupational and environmental factors: Prolonged exposure to toxins like silica dust, asbestos fibers, grain dust, animal droppings, radiation, and indoor hot tubs can harm the lungs. Radiation therapy for lung or breast cancer can also lead to lung damage. 
• Medications: Certain drugs, such as chemotherapy medications, heart drugs (e.g., amiodarone, propranolol), some antibiotics, and anti–inflammatory drugs, can damage lung tissue. 
• Medical conditions: Autoimmune diseases like rheumatoid arthritis, scleroderma, dermatomyositis, polymyositis, mixed connective tissue disease, Sjogren’s syndrome, and sarcoidosis can cause lung damage. 
• Idiopathic interstitial pneumonias: In some cases, the cause of interstitial lung disease remains unknown, and these cases are categorized as idiopathic interstitial pneumonias, with idiopathic pulmonary fibrosis being the most common and severe form. 

Risk factors  

Certain factors can increase your vulnerability to interstitial lung disease, including: 

• Age: Interstitial lung disease predominantly affects adults, although it can occasionally develop in infants and children. 
• Occupational and environmental exposure: If you work in industries like mining, farming, or construction, or if you are regularly exposed to lung–damaging pollutants, your risk of developing interstitial lung disease is heightened. 
• Gastroesophageal reflux disease (GERD): Uncontrolled acid reflux or indigestion can elevate your risk of interstitial lung disease. 
• Smoking: Some variants of interstitial lung disease are more prevalent among individuals with a history of smoking. Active smoking can also exacerbate the condition, particularly if it is accompanied by emphysema.
• Radiation and chemotherapy: Undergoing radiation therapy to the chest or using specific chemotherapy medications can increase the likelihood of developing lung disease.