Pathology Handbook

 New search
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z # ALL

PLEASE NOTE: Recent changes have been made to this Test


 Recent changes for Glucose Tolerance Test

Recent changes for Glucose Tolerance Test
DateFieldChanged FromChanged To

Glucose Tolerance Test

Alternative Names:GTT
Laboratory:Clinical Biochemistry
Test Code:GTT
Specimen Types:Plasma
Container Types:
Fluoride Oxalate
Collection & Request Instructions:Fast for > 8 hours pre procedure

Clinical Use, Protocol and Interpretation.

Transport Instructions between Sites and/or Laboratories:Room Temperature
Additional Notes:

The following Table summarises the 2006 WHO recommendations for the diagnostic criteria for diabetes and intermediate hyperglycaemia.

Diabetes

Fasting plasma glucose      >/=  7.0 mmol/L

OR      2 hr plasma glucose  >/= 11.1 mmol/L              

Impaired Glucose Tolerance

Fasting plasma glucose *    <7.0 mmol/L 

and

2 hr plasma glucose *     >/= 7.8 mmol/L and <11.1 mmol/L

Impaired Fasting Glucose

Fasting plasma glucose         6.1 to 6.9 mmol/L

and (if measured)

2 hr plasma glucose *           <7.8 mmol/L

* Venous plasma glucose 2 hrs after ingestion of 75g oral glucose load

 

DIAGNOSIS of Gestational Diabetes and Diabetes mellitus in pregnancy

* Venous plasma glucose 2 hrs after ingestion of 75g oral glucose load

Fasting

Glucose

mmol/L
 

1hr

Glucose

mmol/L

2 hr

*Glucose

mmol/L

 

               Interpretation      

 

≤5.0

OR

< 10

OR

< 8.5

Normal Glucose Tolerance

5.1-6.9 

 

OR

≥ 10

OR

8.5-11.0

Consistent with gestational diabetes

≥ 7.0

OR

 

OR

≥ 11.1

Consistent with diabetes

mellitus in pregnancy