No, not for specific field.
My nephew started at the age of 16 as a volunteer for a hospital, moved up to the ER checking in patients, then got hired part time while finishing HS, got more hours while finishing college, now he is a full time employee, he got a degree in biology & minor in physcology. His younger brother just got hired as well doing the same thing for another hospital, but it did help them with starting out as a volunteer.
Their will always be a shortage in the medical fields, that would be a great field for her.
Or you can write letters to Endo offices to see if they have any volunteer work that may need to be done.
Maybe she could start some sort of "teenage support group" in your area. Or maybe just volunteer in the pediatric wing of a hospital - wouldn't necessarily have to be thyroid issues - just having had experience with an incurable disease and complications, etc, she would be able to encourage and support other teenagers or even younger children. She knows what misery can be involved and no doubt had to learn patience, coping skills, etc - she could be invaluable for others, of all ages, even if they don't have the same disease.