Welcome. The fact that you don't have bleeding says your inflammation is in a very mild state...a good thing. The fact that it's spread throughout your colon is something that's not so great, especially since your previous sig-scope stated it as limited to the lowest part.
since the appendix is attached to the cecum, I can see that it could have triggered inflammation in that area as well as the rectum (there's a form of UC where it's clear between but inflamed at both ends. Eventually, it can become throughout...which yours has.
Since your stool samples came back negative for giardia...that's a good thing. It's possible the initial infection/parasite has been cleared up.....but probably it's triggering UC.
I'm assuming the rectal meds didn't totally work for you because you still had inflammation high in the colon as well as the appendix inflammation/infection. That area wasn't being treated. Not to say your appendix wouldn't have had to be removed anyway...it might have prevented your entire colon from being inflamed...but that's only assuming with early treatment.
Has the doctor checked you for c-difficile? if not...make sure he does.
Have you had a complete colonoscopy? with lots of biopsies? if not...get an appointment with a GI and get one soon.
My UC started with diarrhea...smelly stools, but lots of diarrhea, no bleeding or mucus....3 years before diagnosis. I had no stool samples and my doc didn't send me to a GI until I started bleeding. Of course, she thought it was only hemmies...I don't consider 20 times a day of explosive bloody razor-like diarrhea to be linked with hemmies...but whatever.
I don't think blood tests can confirm UC...but they can show certain levels that can lead the belief that it's UC. It'll also negate other suspicions....kind of like going through elimination process.
Please do not accept prednisone as your first med if it's suspected you do have UC.
I would strongly suggest you go back on the Salofalk and Asacol or Lialda to help get the entire colon calmed down asap. Since you're in early stages of "something"....those meds are still the best first-line med.
Welcome again....of course, I'm assuming you do have UC....but please don't do the prednisone if the doc says you have to be on it.
Are you in Canada? (salofalk..not in the US)
*Heather*Status: mini flare Dec 28... tapered to every 4th night
~diagnosed January 1989 UC (proctosigmoiditis)
~5ASA: Asacol (6 daily) + Salofalk enemas (increase for flares tapered to maintenance)
~Bentylol (dicyclomine) 20mg as needed
~Probiotic 3(Natural Factors Protec) bedtime + 1 (Primadophilus Reuteri) occasionally
~multi-digestive enzymes as needed ....zymactive 3 - 5x daily
~Ranitidine,Pariet (reflux) Effexor XR 75mg; Pulmicort/Airomir (asthma)
~URSO for PSC (or PBC) 500mg X 2 daily (LFTs back to NORMAL!!)
My doc's logic.. "TREAT (FROM)BOTH ENDS" worth it !!!