I know you're trying to argue from a position of authority so that you can go "hah see I've worked in X profession longer!".

I never said that I do this in a hospital.
I have no clue what an ultrasound can show in these cases.

What I'm saying is that after MY appendix perforated they did not know what it was.
All the tests they did included doing an ultrasound and an x-ray.
They didn't tell me what each test would specifically look for.
Just making the point that it's not an automatic cut and dry "oh that's acute appendicitis".
Especially if you've got someone with high pain tolerance.