Glucose, Gestational Screen (50g)-135 Cutoff

Test Code

8477

CPT Codes
82950

Preferred Specimen

1 mL timed plasma collected in a fluoride oxalate (gray-top) tube

Patient Preparation
Fasting is not required. The patient is given a 50 g dose of glucose and a single blood specimen is obtained 1 hour later.

Minimum Volume

0.5 mL

Other Acceptable Specimens

Plasma collected in: sodium or lithium (green-top) tube • Timed, full tube of whole blood collected in: fluoride oxalate (gray-top) tube • Timed serum collected in serum separator tube (SST®)

Instructions

Serum and plasma submissions must be separated from cells.
Please note: The test should be performed between weeks 24 and 28 of gestation.

Transport Temperature

Room temperature

Specimen Stability

Plasma
Room temperature: 7 days
Refrigerated: 7 days
Frozen: 28 days

Serum
Room temperature: 4 days
Refrigerated: 7 days
Frozen: 28 days

Whole blood
Room temperature: 24 hours
Refrigerated: 72 hours
Frozen: Unacceptable

Methodology
Spectrophotometry (SP)

Setup Schedule

Set up: Daily; Report available: Next day

Limitations

Glucose levels may be depressed if sample is left on clot for an excessive length of time.

Reference Range

<135 mg/dL

Clinical Significance

A value of 135 mg/dL or greater indicates the need for a full diagnostic, gestational glucose tolerance performed in the fasting state to determine if the patient has gestational diabetes.

Performing Laboratory
Quest Diagnostics Nichols Institute
14225 Newbrook Drive
Chantilly, VA 20153

The CPT Codes provided in this document are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed. Any Profile/panel component may be ordered separately. Reflex tests are performed at an additional charge.