Causes of clubbing are fairly anecdotal and usually remain the remit of consultant ward rounds, but here they are:

C – Cyanotic heart disease, cystic fibrosis

L – Lung and liver (Hepatopulmonary syndrome, Lung cancer, Lung abscess)

U – Ulcerative colitis, malabsorption and Crohn’s disease

B – Benign mesothelioma

B – Bronchiectasis

I – Interstitial fibrosis, Infective endocarditis

N – Not COPD – if someone has COPD and clubbing, look for another cause

G – Graves disease (thyroid acropachy)