1. The Causes of Clubbing
In medicine, things are often idiopathic
like how they think pills work if they're homepathic,
But let's start with the chest
'cause I think that's best
My first answer?
that's lung cancer!
mainly non-small cell
and these people aren't well,
But in the younger, cystic fibrosis
chronic coughing? tuberculosis
cause of everything? sarcoidosis
in the older? maybe asbestosis,
which leads us nicely to mesothelioma
not as benign as atrial myxoma,
if I were a dreamer
I'd miss out empyema
or how weakened lungs can't resist
bronchiectasis,
don't forget fibrosing alveolitis
and rarely, infective endocarditis,
it must be bacterial and sub-acute
if not, you’ll look less than astute,
now I've mentioned the heart
and the important part
it’s congenital cyanotic
blood flow can get quite chaotic
and when the shunt is right to left
it's like oxygen theft.
Now I ask you please
to think of GI disease,
inflammed bowel, you got Crohn's and UC

2. how many more causes can there be?!
Coeliac, try not to eat wheat
but there's no great alternative on the high street,
too much cider and I'll get cirrhosis
for non GI, there's thyrotoxicosis
(that's acropachy, some might say
but as far as I'm concerned it's not too far away)
finally, it can be induced in pregnancy
but the most obvious is descendancy.