i have a similair situation. I have had inflammation throughout my colon but in patches. a colonoscopy in 2009 showed inflammation in the rectum, the sigmoid and then skipped to the transverse. 2/2012 cscope showed one isolated patch in the sigmoid and nothing in the rectum. I get alot of pain higher up like you say. i dont have rectum pain.
from 1991- 2006 i was told it was crohns. new gi suspected uc, did that promethues test, it said uc, so she believes i have uc despite the patchiness. i have nothing at all in my term illium. i thought maybe it could be crohns colitis asked my gi, she says no its uc..... I have tried oral entocort which is usually presecibed for crohns but that didnt do much.
i have had luck with lialda, it seems to have cleared everything in my colon except that one stupid patch in the sigmoid.
i do use rowasa as that can reach up to the sigmoid, and so far it has gotten me closer to remission than anything else i have tried.