I have a cousin who has MS and he also has bilateral ankle clonus because of it. It can be somewhat debilitating for him, especially when he's trying to walk.
The ankle clonus is not being treated per say. Doctors have said that the best they can do is treat the underlying condition which is multiple sclerosis. He is getting neurorehabilitation so he is getting physical therapy and takes anti-inflammatory and pain relieving medications. When his MS symptoms are under control, his ankle clonus gets a little better too.