Wilshere was substituted after an hour of the 2-1 Champions League defeat, having appeared to labour with an ankle injury.
After missing more than a year of competitive football before returning last October from an ankle problem, Wenger admitted he would monitor the England midfielder's fitness.
"You could see he was not completely himself and that's why I decided to take him off," Wenger said.
"I think at the moment it's his desire to play, absolutely, but you could see tonight he was handicapped after the first tackle of the game. He landed awkwardly and he looked to me that he was limping a little bit.
"I'll see how he responds in the next two or three days but I will have to wait for the medical assessment."