Relapse and Antibiotic Advice

I was doing really well up until the beginning of this December. My BMs got down to about 5-6 a day, formed with a bit of blood but nothing major. I was starting to get back to normal life, even maybe go back to work. I got my prednisone down from 40mg to 15mg. Things weren't perfect but they were on the up and up. My hemoglobin was also rising again and I was gaining weight. I was feeling very positive!

Then I started having frequent BMs again, very frequent. It all came on very suddenly. We're talking night and day. Undigested food transited faster than ever and all the rapid transit started up the bowel irritation, then bleeding. Now I have full on ulcers again with lots of blood. It felt like an infection but the stool tests from my doc showed nothing. Everything relapsed and now I am stuck in bed again, on 40mg pred, pain killers, and I've lost a big amount of weight. CRP is high and pred doesn't seem to be making a big dent in it. They keep repeating stool tests but it doesn't find anything. I think maybe I am just having such frequent diarrhea that there isn't enough of anything to see.

The only thing I can think of is that I ate a lot of raw rish around that time, almost every day. Lots of salmon and tuna. Sushi is popular here in Vancouver and good quality. Once I regained the ability to eat it, I had it a lot. It was helping me regain weight and fat, and also there's a sushi place very close to me so it was convenient since I don't always have the energy to cook for myself. Maybe that was the problem, I don't know. Food borne illness? I since stopped the sushi and only eat cooked stuff now, but maybe it's too late?

I ended up seeing an infectious disease doctor through my GP. He has prescribed amoxicillin with clauvanic acid to take for two weeks. It's a strong, broad spectrum antibiotic that has been known to cause c. diff colitis. I don't have a history of c. diff though. Online, some UC patients note that their UC got way better from taking this. I am afraid of abx making me permanently worse, and I don't know what to do. The IDS says to take them, my MD says to listen to the IDS, but my history of antibiotics is not good. In the past, IF IT'S THE WRONG TREATMENT, my UC gets worse and lasts a lot longer (many months). Sometimes abx trigger my flares in the first place... but I have to say, the one or two times when I had a genuine bowel infection, the abx ended the flare right away. It was miraculous.

So I don't know what to do. I'm scared to take it but scared to not take it. What scares me is that if this is an acute infection and we don't know what it is, is a good idea to just throw a random antibiotic at it? On the other hand, if it turns out being the right treatment, I could put a major dent in this flare and maybe get back to where I was at before.

How do I decide??? How do I protect myself??? So stressed out!!