I'm glad you're feeling better, UC is terrible and I can relate all too well.
However, I have to let you know that Prednisolon and drugs in general are short term fixes only. You can't take cortico steroids for a long time and your doctor is right, the long term side effects are very bad. Steroids are bad for the average man, they are devastating to people with UC.
Cortico steroids help you in the short term but will mess your body up in the long term. Badly. I know people that have followed the steroid path and they are no longer working, they don't function. One has lost part of his colon in a surgery and now craps out of a tube in his chest. Don't let this be you.
Also, enemas (somewhat work) because they help remove waste and toxins left over from your poor digestion. Fix your digestion and you won't need them. Enemas used long term makes your bowels muscles weak, and disturbs the good intestinal flora. If you want a good bowel cleanse, I'd recommend Lower Bowel Balance by Barefoot (on curezone), it makes your bowels stronger as opposed to being a laxative.
I hope this information is useful (to someone) and you continue to get better.