C peptide test

My daughter was just diagnosed about a month ago with what they think is type 1 diabetes.  She had weight loss, extreme thirst and urination as well as some weakness & fatigue.  She went to the college health services and had a fasting blood glucose test done.  It came back with a level of 252.  She had a few keytones in her urine as well.  That day they sent her to an Endocrinologist.  There they started her immediately on insulin.  About a couple of weeks later, they did A1C test that came back with a level of 10.  I don't see anywhere where they did a C-peptide test.  How can they for sure know that she has type 1 and not type 2??  I see on the blood test they did a GAD65 with a result of 1.85 H?  I am guessing the H means high?  I read somewhere that if a person has a low level C-peptide test it would be consistant of Type 1 and a high level would be with type 2?? I took her to another clinic for some additional blood test and  they checked her Alanine Aminotransferase (liver) and it looks fine, creatinine, potassium, Alubumin, Thyroid Stimulating hormone, Thyroid Peroxiadase (TPO) Antibody, and a Tga-Antibody (for celiac) all were fine and negative.  My question that I can't seem to get a straight answer for is how do they know that she has type 1 and must be on insulin?  Is there another term for the peptide test, or why wouldn't they have done this?  She was only recently diagnosed a month ago and I am curious since we have 3 close family members with type 2 and she had a fasting glucose back in 2006 or 119??  At that time, she was within the scale and so they didn't flag her as high, but as I look back, it was there.  She isn't overweight and does suffer from Asthma (periodically)  Thank you for any insight you could give me.


This discussion is related to GAD-65 AB - What does it mean.

[Super_sally888]

I would guess that her presentation (not overweight, and presenting with acute symptoms of diabetes) and her age would be more typical of typical of type 1 diabetes.  Type 2 diabetes usually develops in older people, who are typically overweight and it develops over time, not so acutely.

THere is also a type 1.5, which is an autoimmune type of diabetes (like type 1), but develops in older people (not children).  Treatment for this may also be insulin, though oral meds may work for a while.

I recommend at this stage you don't question the diagnosis, but work with your daughter to get her blood sugars under control with the insulin and lifestyle measures, and lots of home testing and coordinating with her endo to optimise her meds.  This is very important to prevent complications.  The HA1C of 10 is very high.  They prefer to see numbers less than 6 and the ideal level is about 4.7.    

[Zoelula]

If your daughter is positive for antibodies, than she is Type 1. Type 2 is not an antibody condition; antibodies are actually a more definitive diagnosis of type than c-peptide.  I am a little surprised they just tested GAD65 as the other antibodies are more typical of straight type 1 and GAD65 of LADA/1.5, but the bottom line is the same. I agree with Sally that you and she need to focus on her care now. Your daughter has a lot to learn about managing her diabetes and I suggest she get on a website with more diabetics managing their condition, and more young people. Private message me if you want a url. I also highly recommend the book Using Insulin by John Walsh.