There is a medical distinction between Guts and Balls. We've heard colleagues referring to people with Guts, or with Balls. Do they, however, know the difference between them?
Here's the official distinction; straight from the British Medical Journal: Volume 323; page 295.
GUTS - Is arriving home late, after a night out with the lads, being met by your wife with a broom, and having the Guts to ask: "Are you still cleaning, or are you flying somewhere? "
BALLS - Is coming home late after a night out with the lads, smelling of perfume and beer, lipstick on your collar, slapping your wife on the butt and having the Balls to say: "You're next, Chubby"
I trust this clears up any confusion.
Medically speaking, there is no difference in the outcome; both are fatal.