Wow, I'd never heard of that before but I found this: linky
It certainly sounds smart that your specialist is doing a tick panel.
I hope she feels better soon.
The glands are - of you picture the face of a clock - at 8 & 4 o'clock or 7 & 5 o'clock with the anus in the center like the clock hands rotate.
Boy, I hope someone can find a diagram cuz I don't think I'm explaining it well.
Some folks will comment theat their grey did a lot of butt licking prior to a rupture. That wasn't the case with Gracie, though she would lick occasionally. Nor did she do any butt dragging on the floor.
The vet said it was a good thing it ruptured as that relieved the pressure. Antibiotics fixed it and there was some powder as well. The details will be in that post link.