Actually, I think all three sentences are grammatically correct, although the last sentence may be a bit inappropriate when only only one of the persons who are reading it are in a position to refer someone undergoing medical treatment, and the wording of the penultimate sentence may be stylistically poor.
Of course, if the word "patients" should be "patience," then the "you're" should be "your," and the comma should be removed. In doing so, sentence becomes one of expressing gratitude for your willingness to wait, as opposed to the generous act of referring clients who are receiving medical services from you.
I think it's deliberate, like "stumbit" in some another location within this site.
Information about American English usage here and here. Floating point issues? Please read this before posting. — emc