Please select a type of Diabetes above to get more information
All types of diabetes are characterised by hyperglycaemia, and this may be identified by any of the following:
HbA1c
Fasting glucose*
Random glucose*
Oral glucose test (75 grams)
*An Hba1c can be used to diagnose GDM if the OGTT is not being performed. It is less sensitive and specific than the OGTT, so is not recommended as a routine diagnostic test in GDM.
*A single blood test is a good clue to diabetes but is not sufficient to diagnose it. Perform the formal diagnostic test to confirm: an HbA1c for non-pregnant people and a 75g OGTT for GDM.
In practice, it can sometimes be challenging to diagnose the type of diabetes in non-pregnant patients.
Type 1 Diabetes
Type 2 Diabetes
Type 3 Diabetes
Clinical clues:
Fasting c-peptide: Normal or low
Anti-islet cell antibodies: Positive in >85% cases
Fasting c-peptide: High
Anti-islet cell antibodies: Negative
Fasting c-peptide: Low