My 7-year-old daughter was recently diagnosed with type 1 diabetes. Her first fasting C-peptide was 0.7. Three weeks later, her non-fasting C-peptide was 2.04 and she was negative for antibodies. She is thin, weighs 20 kg (44 pounds). Is it possible she has type 2 or MODY?

Hope that she was diagnosed without being too sick. Antibody negative at diagnosis at that age is quite unusual but depends upon the laboratory doing the antibody tests. In the best laboratories around the world, diabetes antibody levels are not 100% but only about 80% positive in type 1 diabetes. If this were picked up early, then there still could be some insulin production that could explain positive C-peptide levels. Over time, these usually decline, sometimes quickly, sometimes slowly and sometimes in-between. The tighter the glucose control, the more the C-peptide persists. You should have your diabetes team recheck antibody levels in about two to three months to see if they stay negative or change. And, make sure you are working with a good pediatric diabetes team, if not in Ismalia, then in Cairo.

SB