What are the causes of finger clubbing?
A Finger clubbing or hypertrophic osteoarthropathy is a non-specific sign associated with a wide variety of diseases, but the exact pathophysiology is not known.
Certainly, familial or congenital finger clubbing is a known entity.
In cardiology, finger clubbing can be found in conditions as diverse as cyanotic congenital heart disease, atrial myxoma and subacute bacterial endocarditis, while in respiratory medicine, finger clubbing can be found in lung cancer (not usually small cell cancer), fibrosing alveolitis and mesothelioma, as well as suppurative lung disease (empyema, bronchiectasis, lung abscess, cystic fibrosis).
In gastroenterology, finger clubbing can be associated with cirrhosis, gastrointestinal lymphoma, malabsorption (for example coeliac disease) and inflammatory bowel disease (ulcerative colitis, Crohn's disease).
Much rarer is clubbing in the form of thyroid acropachy and unilateral clubbing from an axillary artery aneurysm and arteriovenous malformations.
From this extensive list, it is clear there is relatively little common ground to suggest a common pathophysiological process underlying the development of this physical sign, so well-known to undergraduate medical students.
Gregory YH Lip is a consultant cardiologist, professor of cardiovascular medicine and director of the Haemostasis Thrombosis and Vascular Biology Unit at the University Department of Medicine at City Hospital, Birmingham