Test Code LPS Lipase, Serum
Specimen Required
Patient Preparation: Patients should be fasting before the specimen is collected.
Collection Container/Tube:
Preferred: Serum gel
Acceptable: Red top
Submission Container/Tube: Plastic vial
Specimen Volume: 0.5 mL
Collection Instructions:
1. Serum gel tube must be centrifuged within 2 hours of collection.
2. Red-top tube must be centrifuged, and the serum aliquoted into a plastic vial within 2 hours of collection.
Useful For
Investigating pancreatic disorders, usually pancreatitis
Method Name
Colorimetric Rate Reaction
Reporting Name
Lipase, SSpecimen Type
SerumSpecimen Minimum Volume
0.25 mL
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Serum | Refrigerated (preferred) | 7 days | |
Frozen | 365 days | ||
Ambient | 7 days |
Reject Due To
Gross hemolysis | Reject |
Other | Collection tubes with glycerol-lubricated stoppers |
Clinical Information
Lipases are enzymes that hydrolyze glycerol esters of long-chain fatty acids and produce fatty acids and 2-acylglycerol. Bile salts and a cofactor, colipase, are required for full catalytic activity and greatest specificity. The pancreas is the primary source of serum lipase. Both lipase and colipase are synthesized in the pancreatic acinar cells and secreted by the pancreas in roughly equimolar amounts. Lipase is filtered and reabsorbed by the kidneys. Pancreatic injury results in increased serum lipase levels.
Reference Values
13-60 U/L
Interpretation
In pancreatitis, lipase becomes elevated at about the same time as amylase (4-8 hours). But lipase may rise to a greater extent and remain elevated much longer (7-10 days) than amylase.
Elevations 2 to 50 times the upper reference have been reported. The increase in serum lipase is not necessarily proportional to the severity of the attack. Normalization is not necessarily a sign of resolution.
In acute pancreatitis, normoamylasemia may occur in up to 20% of such patients. Likewise, the existence of hyperlipemia may cause a spurious normoamylasemia. For these reasons, it is suggested that the 2 assays complement and not exclude each other, and that both enzymes should be assayed.
Cautions
Certain drugs such as cholinergics and opiates may elevate serum lipase.
Renal disease may elevate the serum lipase.
Method Description
The lipase method is an enzymatic colorimetric method in which lipase catalyzes the hydrolysis of a natural 1,2-diglyceride to form monoglyceride and fatty acid. Monoglyceride is hydrolyzed by monoglyceride lipase to form glycerol and fatty acid. Glycerol is then phosphorylated by glycerol kinase in the presence of ATP to form glycerol-3-phosphate, which is oxidized by glycerol-3-phosphate oxidase to form dihydroxyacetone phosphate and hydrogen peroxide. Subsequently, hydrogen peroxide reacts with 4-aminoamtipyrine and sodium N-ethyl-N-(2-hydroxy-3-sulfopropyl)-m-toluidine in the presence of peroxidase to form quinone diimine dye. The dye absorbs light at 550 nm. The rate of increase in absorbance at 550 nm is directly proportional to the pancreatic lipase activity in the specimen. The method is sensitive and specific for pancreatic lipase and utilizes co-lipase and deoxycholate as activators.(Package insert: Equal Diagnostics Lipase reagent, Exton, PA. V2.0 03/2019)
Day(s) Performed
Monday through Sunday
Report Available
Same day/1 to 2 daysPerforming Laboratory
Mayo Clinic Laboratories in RochesterTest Classification
This test has been cleared, approved, or is exempt by the US Food and Drug Administration and is used per manufacturer's instructions. Performance characteristics were verified by Mayo Clinic in a manner consistent with CLIA requirements.CPT Code Information
83690
LOINC Code Information
Test ID | Test Order Name | Order LOINC Value |
---|---|---|
LPS | Lipase, S | 3040-3 |
Result ID | Test Result Name | Result LOINC Value |
---|---|---|
LPS | Lipase, S | 3040-3 |