Many different instabilities can be related to getting hyperglycemia, type 2 diabetes, and insulin resistance. Commonly, a few basic tests are being done just to evaluate type 2 diabetes due to various reasons. Probably, this may lead to improper evaluation of the real disease. Can you tell that which tests can be done to evaluate all possibilities/conditions related to hyperglycemia, type 2 diabetes, insulin resistance, etc.?

In the U.S., initial evaluation of patients with hyperglycemia or diabetes runs something like this:

For a high blood sugar above 126 mg/dl [7.0 mmol/L], if it is confirmed, the diagnosis is diabetes. The diagnosis requires elevated levels on more than one occasion.

You can check C-Peptide with the glucose to see if the value is appropriately elevated or not. If it is elevated, it is more likely type 2 diabetes.

Islet cell markers of autoimmunity include anti-GAD, anti-ICA, and insulin autoantibodies. If these are high, they indicate type 1 diabetes.

The above, in addition to clinical indicators, are generally what are used to make a diagnosis of type 1 or type 2 diabetes.

There are additional things that can be done and may occur with a research study, that give more information about correct assignment of type 1 or type 2 diabetes. These include such things as the following:

Serial oral glucose tolerance testing or mixed meal challenge testing. Some of those with type 1 diabetes may have presentation like type 2 at first, but may have a fall off in beta cell function. These tests can pick that up.

I.V. glucose tolerance testing to evaluate beta cell function.

Measures of insulin resistance, which include clamp tests, minimal model analysis, or use of fasting glucose and insulin responses.

JTL