Lactose Tolerance Test, 5 Specimens (50g)

Test Code

7675

CPT Codes
82951, 82952 (x2)

Includes

Fasting specimen, 1/2-hour, 1-hour, 2-hour, and 3-hour specimens

Preferred Specimen

Five - 1 mL plasma specimens collected in fluoride/oxalate (gray-top) tubes

Patient Preparation
Note: This cannot be performed at a patient service center because of the preparation step required for the lactol solution.

Fasting required. Fasting is defined as no consumption of food or beverage other than water for at least 8 hours before testing.

Minimum Volume

0.5 mL for each specimen

Other Acceptable Specimens

Plasma collected in: Lithium heparin (green-top) tube • Sodium heparin (green-top) tube • Serum (separated from cells immediately) • Spun serum separator tube (SST)

Instructions

Immediately after a fasting specimen is obtained, have patient ingest a 50 g dose of lactose (supplied by laboratory). Draw subsequent specimens 1/2, 1, 2 and 3 hours later. Label each with the specific draw time.

Note: Children should receive 1.75 g lactose per kg ideal body weight, up to 50 g.

Transport Container

Fluoride/oxalate (gray-top) tubes

Transport Temperature

Room temperature

Specimen Stability

Sodium fluoride plasma
Room temperature: 7 days
Refrigerated: 7 days
Frozen: 28 days

Heparinized plasma
Room temperature: 48 hours
Refrigerated: 7 days
Frozen: 28 days

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

Whole blood (gray-top) tube
Room temperature: 24 hours
Refrigerated: 72 hours
Frozen: Unacceptable

Note: Serum and plasma submissions must be separated from cells.

Reject Criteria (Eg, hemolysis? Lipemia? Thaw/Other?)

Unspun serum or plasma separator tube (SST or PST) • Red-top or green-top tube (serum or heparinized plasma not separated from cells) • Anticoagulants other than lithium heparin, sodium heparin or fluoride/oxalate

Methodology
Spectrophotometry (SP)

Setup Schedule

Mon-Sat

Report Available

1 day

Clinical Significance

Results may be used to evaluate deficiency of small bowel mucosal lactase, which may be associated with intolerance to lactose, manifested by diarrhea and other symptoms following ingestion of milk.

Performing Laboratory

Quest Diagnostics-Pittsburgh Lab

875 Greentree Road

Pittsburgh, PA 15220-3508

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.