I'm building quite a little library of thyroid books - another has just popped through the letter box and already I've learned something new! Hypothyroidism by Mark Starr.
I'd only come across the term myxedema coma and so had dismissed the term as I had assumed it only applied to last stages of serious hypothyroidism.
But no! The first chapter in my new book tells me something quite different and that I have myxedema. The test is to try to pinch the skin on the upper arm and you should be able to pinch it so skin comes away with fingers close together. I can do this on my wrist but on my upper arm the 'pinch' is over an inch thick and I've got skinny little arms!
This type of swelling is apparently unique to hypothyroidism and so specifically distinctive and diagnostic. Doctors used to do physical examination of patients but are now not trained to do this - this diagnostic clinical finding, used prior to blood tests, has been forgotten.