14 year-old teen/Hashimotos/Insulin resistance

[Jogger5]

My daughter was diagnosed at 9 years old with "Hashimotos". She takes .25 & .50 synthroid alternating days. She's done very well until this past Thanksgiving when she had a tonsilectomy and had a very hard time recovering. She lost nine lbs. in two weeks, at her two week post-op she still was very weak and had little or no energy. We visited her endocrinologist and he did blood work and after three long weeks of waiting her thyroid was normal but her c-peptide was 7.9 and her HDL was 26, my daughter is slender and fit and also physically active. He said she's Insulin Resistance and said he wanted to put her on 100mg. of Januvea. She took it for five days and I took her off of it because it has not been tested in persons under 18 years old. After seven weeks she still can't go to school, the fatigue is horrible. We visited an internist here in our town and they suspect "mono". The titer test will be back tomorrow. Her endocrinologists explained about the high c-peptide, but he said she doesn't fit the profile of an IRS patient, he's very puzzled. He's known as one of the best Endo. physicians in the southeast. He's in Atlanta, GA. I've recently made her an appt. with a pediatric endo. physician at Children's Health Care of Atlanta. I just wanted to know if you have any idea what conidtion or disease she could have. All of her other levels were great. Glucose serum was 73 and all the other levels in the CMP were of normal levels. All the lipid panel 2 was normal with the exception of the C-peptide and HDL. She's now home recupperating possbily for another 4 to 8 weeks. Please shed some light on this baffling condition.

[Deanna L Aftab Guy, MD]

Wow!!! I have not even used Janeuvia yet as you mentioned not approved under 18, I would have repeated the C peptide first before treating.
Second, if she is insulin resistant these folks do not lose weight rather they are overweight, have high insulin levels and this should be checked as well as the C-peptide.
I think that the tonsillectomy caught her for a loop! I lost 11 lbs when I had mine as an adult-was exhausted.
With history of one autoimmune disease I would be concerned about another-so celiac antibodies and adrenal testing would be on my list first!
Wait to see the other peds endo and hope that you get a better discussion about what they are thinking about, labs in a child who has lost weight and is weak who has history of thyroid disease includes
cmp
cbc,
free T4, TSH
celiac antibodies
anti-21 OH ase antibodies-this is a send out but may help later
random cortisol and acth level or just a plain old 1 microgram acth stim test to see how your daughter's brain is communicating with her adrenal glands during this time of illness.
Your endo has their own plan no doubt so work it through and wait before aggressive treatment till you are very clear about the results and make sense of the diagnosis.
Mono is pending, that will help, she should really take in the fluids while waiting and get her nutrition the best way possible, my mom had to blenderize my food-yuck! I was 28 years old eating baby food!
So if she can take a shake with some carnation instant breakfast in it for added protein that will help alot.
I am thinking the C peptide was a red herring-that is med speak for abnormal lab result that gets our attention and never shows its face again!