Macroamylase Determination
Also known as: MACROAMY
Use
Macroamylase determination is critical for diagnosing macroamylasemia, a condition where abnormal enzyme complexes prevent normal amylase activity, potentially leading to misdiagnosis of pancreatitis due to elevated serum amylase levels. The test involves measuring total amylase and monomeric amylase, with monomeric amylase results above the upper reference limit indicating hyperamylasemia, and a percent monomeric less than 71 percent suggesting macroamylase presence.
Special Instructions
For optimal results, serum or plasma should be separated from cells as soon as possible after collection, ideally within 2 hours. This test is not FDA cleared but is performed in a CLIA certified lab ensuring quality standards.
Limitations
The test may not discern all causes of elevated amylase levels. It specifically does not measure macroamylase directly; instead, the presence of macroamylase is inferred from low monomeric amylase percentage. Samples containing calcium chelating anticoagulants (e.g., citrates, EDTA, oxalates) are unacceptable and may cause erroneous results.
New York Approved
Methodology
Other
Biomarkers
LOINC Codes
- 1798-8
- 2591-6
- 26011-7
Result Turnaround Time
2-9 days
Related Documents
For more information, please review the documents below
Specimen
Plasma
Volume
2 mL
Minimum Volume
1.1 mL
Container
ARUP Standard Transport Tube
Collection Instructions
Collect in a plasma separator tube, serum separator tube, or plain red. Allow specimen to clot completely at room temperature.
Storage Instructions
Refrigerated transport is required. Stability after separation is maintained ambient for 1 week, refrigerated for 1 month, or frozen for 1 month.
Causes for Rejection
Specimens containing calcium chelating anticoagulants such as citrates, EDTA, or oxalates.
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 1 week |
| Refrigerated | 1 month |
| Frozen | 1 month |