The lungs possess a complex structure, comprising airways, air sacs (alveoli), interstitium (a microscopically thin lining between the air sacs), and blood vessels, all enveloped by pleura, a thin lining. Lung diseases can arise from issues in any of these components. Classification of lung diseases often hinges on the underlying disease process and its impact on normal lung function.
- Obstructive lung diseases: These conditions involve a reduction in exhaled air flow due to airway narrowing or blockage. Examples include asthma, emphysema, and chronic bronchitis.
- Inflammatory lung diseases: Conditions affecting lung elasticity and gas exchange in the alveoli. Diseases such as pneumonia, emphysema, sarcoidosis, idiopathic pulmonary fibrosis, and interstitial lung diseases fall under this category. Prolonged inflammation may lead to fibrosis/scarring, resulting in loss of lung elasticity.
- Infections: Infections, like pneumonias (bacterial and viral) and tuberculosis, can lead to inflammation, often considered separately due to their infectious nature.
- Tumors: Lung cancers can impede airflow and/or damage lung tissue.
Many lung diseases exhibit overlapping disease processes; for instance, emphysema involves both airflow obstruction and gas exchange issues. Common types of lung diseases include asthma, pneumonia, acute and chronic bronchitis, emphysema, and lung cancer.
Certain diseases affecting lung blood vessels may also impact lung function, typically categorized as cardiovascular diseases. Lung diseases have emerged as significant contributors to global mortality and disability. Therefore, if you experience symptoms suggestive of lung disease, prompt consultation with a medical professional is crucial.