I have MS but also have terrible allergies and sinuses so I can't say whether my loss of sense of smell is MS related or not. I just assume it is from sinus issues as I have been that prior to MS diagnosis.

My MRI does show a cyst in one of my sinuses. This cyst gets irritated during allergy season as well as during colds/flus. Once irritated it swells, blocks off that nasal passage and I can't smell a thing.

On the flip side, we talking MS here so I guess anything is possible. Just think of all the possibilities MS brings. LOL.