Bowel Disorders :: Thick White Anal Discharge

I've suffered from mucus-coated stools and a light anal discharge for years and years, after having a peri-anal abcscess misdiagnosed as piles at the age of 17. This resulted in having an urgent operation to drain the ruptured abscess. 11 years after this surgery I was diagnosed with a multiple fistula-it was incredibly painful by this time as I had ignored the discharge etc for all those years, but it became unbearable. A year ago I had a fistulectomy, which has healed well. During the surgery they found a lump in my bowel. They took a biopsy and I was told it came back clear. For the last three months the discharge has returned-it's quite runny and not foul smelling, but I know also pass strange, fatty like things from my anus when I pee. It feels like I need to pass wind when I wee and then these bits come out, a couple of lumps of what look like slightly under cooked egg white. I am also still having mucus covered stools with some bright red blood and some darker blood when I wipe.

I really don't want to have to go through more 'camera up the bum' procedures but do you think I should?
Thanks for any help or advice anyone can offer me.