Lactose Tolerance Test, 5 Specimens (50g)
Test code
CPT code(s)*
Test resources
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Details
Includes
Fasting specimen, 1/2-hour, 1-hour, 2-hour, and 3-hour specimens
Methodology
Spectrophotometry (SP)
Specimen requirements | |
|---|---|
| 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. |
| Preferred specimen(s) | Five - 1 mL plasma specimens collected in fluoride/oxalate (gray-top) tubes |
| Alternative specimen(s) | Plasma collected in: Lithium heparin (green-top) tube • Sodium heparin (green-top) tube • Serum (separated from cells immediately) • Spun serum separator tube (SST) |
| Minimum volume | 0.5 mL for each specimen |
| Collection instructions | Obtain fasting specimen. Immediately after fasting specimen is obtained, have the patient ingest a 50 g dose of lactose (obtained through client supply). Collect subsequent specimens 1/2, 1, 2, and 3 hours, labeling each sample at the time of draw with the specific draw time. LacTest Preparation instructions: If using LacTest, dissolve two 25 g packets into 6-8 oz of water to make the 50 g dose required. Mix thoroughly. Because of the relative insolubility of lactose, mix frequently during ingestion as necessary. If any lactose precipitate remains in the glass, swirl with a small amount of additional water and drink. For pediatric use, dissolve 1 gram of LacTest for every 1 kg (2.2 lbs) of the patient's body weight in 6-8 oz of water. |
| 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 | 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 |
Reference ranges are provided as general guidance only. To interpret test results use the reference range in the laboratory report.
*The CPT codes provided are based on AMA guidance and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payer being billed.
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