During a recent sigmoidoscopy a small patch of inflammation was found on the left side of lower bowel. What is the most likely outcome?

Hard to say. Given the limitted info you gave, it is hard to tell what exactly it is. Could be from recent mild infection, early colitis, lymphocytic/spastic colitis, or it may not be much at all.... Why was the procedure done? I assume some tissue sample/biopsy was done...If so, waite for the result.. Good luck...Keep us informed..
Depends on biopsy. The significance of a "patch of inflammation" will depend almost entirely on the findings of a biopsy of the affected area. There are serious bowel diseases such as crohn's disease, that cause scattered patches of inflammation.