Which diseases are commonly associated with clubbing of the fingers?

Clubbing of the fingers is a clinical sign characterized by an abnormal enlargement of the distal phalanges, and it is often indicative of chronic hypoxia or lung disease. The conditions commonly associated with clubbing include chronic obstructive pulmonary disease (COPD), cystic fibrosis, and lung cancer.

COPD leads to chronic respiratory impairment, which can result in low oxygen levels over time, prompting the development of clubbing. Cystic fibrosis, a genetic disorder that affects the lungs and digestive system, is also associated with chronic lung infections and inflammation, leading to clubbing. Lung cancer can cause clubbing as a result of increased vascular growth and the presence of tumors affecting lung function and oxygenation.

In contrast, while the other options may present with various respiratory symptoms, they do not typically lead to clubbing. Conditions such as asthma and acute bronchitis are often associated with reversible airway obstruction rather than chronic hypoxia. Acute diseases like pneumonia and influenza tend to cause temporary symptoms rather than the prolonged hypoxia that causes clubbing. Emphysema and bronchiectasis can lead to serious lung function issues, but without the specific pathophysiological changes seen in the diseases listed in the correct answer, they are less commonly connected to clubbing