Type of test Blood
Normal findings
0-160 units/L or 0-160 units/L (SI units) (Values are method dependent.)
Test explanation and related physiology
There are many forms of lipase acting within the body. All are esterases that assist the body in metabolism of fats. The most commonly tested lipase is pancreatic lipase (commonly referred to as lipase or serum lipase). The most common cause of an elevated serum lipase level is acute pancreatitis. Lipase is an enzyme secreted by the pancreas into the duodenum to break down tri glycerides into fatty acids. As with amylase , lipase appears in the bloodstream after damage to or disease affecting the pancreatic acinar cells.
Because lipase was thought to be produced only in the pancreas, elevated serum levels were considered to be specific to pathologic pancreatic conditions. It is now apparent that other conditions can be associated with elevated lipase levels. Lipase is excreted through the kidneys. Therefore elevated lipase levels are often found in patients with renal failure. Intestinal infarction or obstruction also can be associated with lipase elevation. However, the lipase elevations in nonpancreatic diseases are less than three times the upper limit of normal compared with those in pancreatitis, in which they are often 5 to 10 times normal values.
In acute pancreatitis, elevated lipase levels usually parallel serum amylase levels. The lipase levels usually rise a little later than amylase (24-48 hours after the onset of pancreatitis) and remain elevated for 5 to 7 days. Because lipase peaks later and remains elevated longer than serum amylase, it is more useful in the diagnosis of acute pancreatitis later in the course of the disease. Lipase levels are less useful in more chronic pancreatic diseases (e.g., chronic pancreatitis, pancreatic carcinoma). Another lipase is Lipoprotein Lipase. When this enzyme is deficient (as exists in familial lipoprotein lipase deficiency [LPLD]), triglycerides build up in several organs (e.g., skin, bloodstream, muscles, liver, spleen, and brain). ELISA testing can reveal diminished lipoprotein activity (particularly in a negative response to Heparin injection). The diagnosis of LPLD can be confirmed by detection of a mutant lipoprotein lipase gene.
Interfering factors
* Drugs that may cause increased lipase levels include bethanechol, cholinergics, codeine, indomethacin, meperidine, methacholine, and morphine.
* Drugs that may cause decreased levels include calcium ions.
Procedure and patient care
• See inside front cover for Routine Blood Testing.
• Fasting: yes
• Blood tube commonly used: red
Abnormal findings
- Acute pancreatitis
- Chronic relapsing pancreatitis
- Pancreatic cancer
- Pancreatic pseudocyst
- Acute cholecystitis
- Cholangitis Extrahepatic duct obstruction
- Renal failure
- Bowel obstruction or infarction
- Salivary gland inflammation or tumor
- Peptic ulcer disease
