Sign in →

Test Code LAB5712 Glucose Challenge Test, 50 G/1 Hour (Gestational Diabetes Screen), Plasma

Performing Laboratory

Barnes-Jewish Hospital Laboratory

Methodology

Enzymatic (Hexokinase)

Literature References:

Package insert: Glucose/HK, Roche Corporation, 06/2018.

Specimen Requirements

This test is utilized in screening for gestational diabetes among women with appropriate risk factors, and is usually performed during weeks 24 to 32 of pregnancy.

 

Patient Preparation:

Fasting is not required.

 

Collection Procedure:

1. Give patient 50 g glucose tolerance beverage.
2. Draw specimen 1 hour post consumption.

 

Specimen Type: Plasma

Container/Tube: Grey top (potassium oxalate/sodium fluoride)

Specimen Volume: Full tube

 

Day(s) Test Set Up

Monday through Sunday
Turnaround Time:
STAT: 1 hour after receipt in laboratory
Routine: 2 to 4 hours after receipt in laboratory

Test Classification and CPT Coding

82950

Reference Values

≤ 140 mg/dL

Critical result (automatic call-back): ≤ 54 mg/dL or ≥ 450 mg/dL

A glucose value of >140 mg/dL generally indicates the need for a full diagnostic tolerance test. See LAB5713 Glucose Tolerance Test, 100 G/3 Hour (Gestational Diabetes Diagnostic), Plasma.

Literature References:

1. Diabetes Care 2005;28:Supplement 1,S37-S42.

2. Report of the expert committee on the diagnosis and classification of diabetes mellitus. Diabetes Care 2020;43: Supplement 1,S14-31.

Specimen Transport Temperature

Ambient

Additional Information

For BJH Laboratory Use Only
Alternate Tube:

1 dark green-top (lithium heparin) tube

1 lavender-top (EDTA) tube

1 mint green-top (lithium heparin) tube

1 red-top tube

Laboratory Processing Instructions:

Test performed in BJH Core Lab.  Processed by automated line for delivery to the Cobas 8000. Completed specimens are stored refrigerated for 5 days. 

Test performed in South County Siteman and Ambulatory Cancer Building Lab.  Centrifuge sample and deliver to the Cobas.  Completed specimens are stored refrigerated for 5 days. 

Special Instructions

See Analyte Stability Chart under General Information for a complete list.

LOINC Code Information

Name LOINC Code
Glucose- 1 hour post 50 g glucose PO 1504-0