It's a great relief when something is finally pinned down like that and has a simple treatment. I had a couple of acute and chronic periods myself, both came up a mystery and ended up having healing which sorted them each time. The second did follow an infection which left a typical lasting effect, and glad they do have at least one clear disorder now as so far chronic fatigue of all types which can't be detected in a blood test has generated a lot of money for therapists and little actual effective treatment (I can say this as I am a therapist, and see physical symptoms being passed over to us as doctors can't suss them out as an abdication of responsibility in the 'too hard' file). We can do certain things to relieve symptoms when stress makes them worse, but we're not actually medically capable!