Testing & Diagnosis for Type 2 Diabetes in Children

At Boston Children’s Hospital, we know that the first step in treating your child is forming an accurate and complete diagnosis.

Often, clues are when a child is very thirsty and needs to urinate frequently. Your child’s doctor may also order blood and urine tests including:

  • hemoglobin (A1C) test: indicates average blood sugar level for the past two to three months

  • random blood sugar test

  • fasting blood sugar test: taken after an overnight (eight-hour) fast

  • oral glucose tolerance test: a two-hour test that includes checking blood sugar after your child drinks a prescribed sugar drink

  • check for autoantibodies in the blood less common in type 2 diabetes (vs. type 1)

  • check for the presence of ketones (byproducts from the breakdown of fat in children without enough insulin) in the urine or blood

Test results may need to be confirmed with a second test on a different day, so it’s possible that your child will have blood drawn more than once. Distinguishing between type 1 and type 2 diabetes in children can sometimes be difficult, and your child's doctor may need to do additional testing or monitor your child for some time before the type of diabetes can be confirmed.

Is it diabetes?

Your child will be diagnosed with diabetes if her:

  • blood glucose is 126 mg/dL or higher first thing in the morning before eating or drinking (fast for at least eight hours)
  • blood glucose is 200 mg/dL or higher at any time if symptoms of high blood sugar are also present
  • blood glucose is 200 mg/dl or higher at two hours during a standard oral glucose tolerance test
  • hemoglobin (A1C) test is 6.5 percent or higher 

Children who are considered to be at risk for type 2 diabetes should be tested periodically, regardless of whether they show signs or symptoms. (For details on risk factors, see Who’s at risk tab.)