C-Peptide and pre diabetes

Hi there. My daughter is 12 and has been having elevate post prandial readings occasionally over the course of the last six months. She has visible skin discolouration showing insulin resistance and has been having increased thirst, tiredness and dizziness also.

Her dad is T1, and my side has a massive family history of T2.

Her latest test came back normal except for her GTT.
Fasting was 5.4 (97)- which is ok
1 hour: 11(198)
2 hour: 10.4 (187)

HBA1C was 5.3%

Her C peptide was normal. In the middle of the reference range.

Antibodies are yet to come as the lab need up to 14 days for those.

I have found documents saying that CPeptide doesn’t go low until T1 is closer to developing, is anyone knowledgable on this?

My gut says it’s T1, and her insulin resistance is because her body is trying hard. But I don’t know. She is not quite done with puberty so not sure if that’s affecting bsls. But we’ve seen a few readings over 6 months of 160-180’s and on the weekend she had a 14.7 (264)

This truly could go either way, and you and your medical team really need to see those test results before attempting a firm diagnosis.

That said, here are some general observations.

  • Given the “massive family history” of T2 on one side, plus the fact that the genetic component of T2 is established beyond question, don’t discount the possibility, yet.

  • Insulin resistance can and does occur with T1, sure, but it’s far more prevalent in T2.

  • Regardless of type, 10.4 after 2 hours ain’t normal; something’s off the rails. But you knew that.

  • C-pep is useful but not definitive by itself. In early stages of T1 or LADA, it can be very erratic. Essentially the pancreas sputters, sometimes producing like it’s supposed to and other times, not.

Bottom line, you need the big picture (i.e., the missing tests) before concluding anything definite. And whatever they do or don’t indicate, she bears careful watching going forward. The situation is, as they say, fluid.

And a personal opinion, or perspective, or whatever you care to label it: at the end of the day, it doesn’t matter whether she’s Type 1, Type 2, or Type 37. What counts is effective control, however you achieve it. Eyes on the prize.

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Yea, definitely not sure what the situation is with your little one, but I would say that when I was first diagnosed with diabetes, I had a c-peptide that was in the normal range, if a bit on the lower side (1.11ng/mL) . However when I was first diagnosed, they had deemed me to be t2. After my second c-peptide reading of 0.84 ng/mL, they saw that it had decreased and while it was still technically within the range of between 0.78-5.19, it was clear that I was actually a t1 diabetic. There were other reasons for the change in my diagnosis, but this was cited as one of the main ones.

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Thanks for your reply. I feel more content with all this information now and I’ll leave it alone.

We will wait for tests and ask for a referral to a hold endo to manage whatever we are looking at! Thanks for your advice

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