Maybe someone can help me with a similar problem. My dd is going to be 15 in a couple of weeks. Her armpits are very dark and she has a dark ring around the back of her neck and between her breasts (acanthosis negricans). Her pediatrician checked her fasting insulin and it was low. Does anybody know if this could be the start of PCOS or type 1 diabetes. I have checked her glucose and the doctor has too but it is always around 100 or 110. Is her body somehow compensating now for the low insulin but later it will really give her problems? She is 5' 4" and weighs 150 pounds. Should she see an endocrinologist or what other reason could there be for having the dark patches?