I have no idea how far you want to fly, but we go to Children’s Hospital of Wisconsin.  They have patients from about a 4-state area.  Our Dr. is Dr. Paola Palma-Sisto in the endocrine clinic, but we usually see the NP Pam Swenerton.  There are a few other doctors in the clinic.  Usually they are booked 6 months in advance, I think.  Our son is only 8 mos, so they actually have to create appts for us so we can get in every 3-4 months.  It may help if your dr. can give you a referral.  The website is www.chw.org, phone is 414.266.2000.