Ditto above. Definition of REFRACTORY:
1: resistant to treatment or cure <a refractory fulminant lesion> <had disease that was extremely refractory to multiple intensive therapies—Michelle L. Bennett et al>
One can be refractory to a particular medication (e.g., steroid-refractory) but responsive to others. One can be refractory to all treatments for a particular disease, which in the case of UC would mean surgery is something on your horizon. Not sure the context in which refractory is used.