An A1c was drawn on a two-month-old by mistake (supposed to be a hemoglobin electrophoresis) and it was 2.6. I was wondering if there are normative values for children of this age. In this otherwise normal newborn (with sickle cell trait on his newborn screen), should I be concerned?

This is an excellent question and the short answer is “YES” – an A1c obtained in this young of a child must be interpreted with caution. The A1c value not only reflects the proportion of glucose that has been around to “stick” to the protein called hemoglobin, but it also reflects the quantity and QUALITY of the hemoglobin. The A1c also reflects overall glucose concentration over the prior 8 to 12 weeks.

So, an A1c in a two-month-old may not be all that informative. Furthermore, new babies still have a specific variant of hemoglobin that typically only occurs in fetus and for a few months thereafter. This “fetal hemoglobin” has a different attraction for glucose than typical normal hemoglobin. In addition, other qualitative hemoglobin variants, such as sickle cell hemoglobin, also have different affinities for glucose. The method by which the A1c is measured may be influenced significantly by these hemoglobin variants.

My guess is that the “true” A1c of the infant is normal. I also presume that you were not concerned with the child actually having diabetes.

If you wanted to pursue this, 1 way would be to ask for a “total glycohemoglobin (total GHb)” – method that measures ALL the various hemoglobins with glucose attached. A normal total GHb typically has a slightly higher normal range than an A1c.

DS