Back to Ask the Diabetes Team Ask the Diabetes Team

From a pathologist in Indiana, USA:

The published recommendation for performing an oral GTT in adults is to switch from three-hour hour, 100 gram load to two-hour, 75 gram load testing, but I cannot find in the literature any specific citation which states whether the same criteria can be used in kids. I realize that OGTT is not recommended by evidence based medicine criteria and that a single random blood glucose of 200 mg/dl [11.1 mmol/L] is okay for diagnosis and that most kids present with obvious DKA/hyperglycemia, etc and do not need an oral glucose load.

Secondly, if the two-hour glucose tolerance test can be used in children instead of the three-hour test, do you base your glucose load on 1.75 grams of glucose per kilogram of ideal body weight, a ratio of kid body surface area to ideal adult (1.73) times 75 grams or what?

I'm a community pathologist so please realize that I get all kinds of requests from primary care doctors so I need some documentation of why I refuse their test request if necessary. This stuff isn't in the pathology literature.


It is not really surprising that you have not been able to find adjusted criteria for the glucose tolerance test in children. Years ago, we used to use 1.75 grams of glucose per kilogram of ideal body weight as a standard dose, but the length of the test and the fact that ' Glucola' (which was how it was usually given) made a good many children throw up meant that it fell into disrepute.

The oral glucose tolerance test is really no longer used and nowadays, as you point out, a fasting blood glucose of grater than 126 mg/dl [7 mmol/L] or a random one that is greater than 200 mg/dl [11.1 mmol/L] would be diagnostic, although a single assay that is marginal needs to be repeated because stress can make a significant difference to blood sugar.

Since most children with new onset have type 1A (autoimmune) diabetes, we would normally get antibody tests and a hemoglobin A1c to confirm the diagnosis. If an additional measure of glucose intolerance is needed, it would be more common nowadays in children to do an intravenous GTT and measure insulin levels at one and three minutes after the i.v. glucose load. Except for the antibody test, the same criteria would apply to the increasing number children suspected to have type 2 diabetes.


[Editor's comment: See Diagnosis in Consensus Guidelines 2000: ISPAD Consensus Guidelines for the Management of Insulin-Dependent (Type 1) Diabetes (IDDM) in Childhood and Adolescence. SS]

Original posting 10 Oct 2002
Posted to Diagnosis and Symptoms


  Back to Ask the Diabetes Team Return to the Top of This Page

Last Updated: Tuesday April 06, 2010 15:09:38
This Internet site provides information of a general nature and is designed for educational purposes only. If you have any concerns about your own health or the health of your child, you should always consult with a physician or other health care professional.

This site is published by T-1 Today, Inc. (d/b/a Children with Diabetes), a 501c3 not-for-profit organization, which is responsible for its contents. Our mission is to provide education and support to families living with type 1 diabetes.
By using this site, you agree to our Terms of Use, Legal Notice, and Privacy Policy.
© Children with Diabetes, Inc. 1995-2018. Comments and Feedback.