This is a very complex history and certainly warrants a thorough evaluation of the sinuses, airways etc. It is impossible to tell you what is the problem. If someone has a CT scan that shows the sinuses to be "filled" as you have described, it is hard to state that they are not infected without a culture for bacteria and fungal infections. The most common cause of "filled sinuses" is a chronic inflammatory process caused by a chronic infection. Such an infection could cause any and all of what you have described, including the hives. I would try to get to the bottom of the "filled sinuses" as the first step to this very difficult and prolonged problem.
best wishes
Alex (Notebook)