Lipase Test is usually used to find out if a patient have high Lipase levels in the blood as a result of acute pancreatitis. Lipase is an enzyme that catalysts the process of breaking down triglycerides and other fats into fatty acids. Pancreas is the gland which secretes Lipase. As with blood amylase, damage to Pancreatic Acinar Cells cause blood lipase levels to increase. Unlike Amylase Test, however, Lipase Test is more specific in the evaluation of pancreatic disease.
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 as compared with pancreatitis, in which they are often 5 to 10 times normal values. Still other conditions such as cholangitis, mumps, cholecystitis, or peptic ulcer are more rarely associated with elevated lipase levels.
Lipase levels usually increase along with amylase blood levels. Blood Amylase levels usually increase before Lipase levels however. Lipase levels usually rise 24 to 48 hours after the onset of pancreatitis. Once increased, Lipase levels stay high around 5 to 7 days. Because they peak later and remain elevated longer than the serum amylase levels, serum lipase levels are more useful that serum amylase in acute pancreatitis late diagnosis. However, when it comes to diagnosing more chronic pancreatic diseases (e.g., chronic pancreatitis, pancreatic carcinoma), Amylase Test is more useful.
The normal lipase levels ranges between 0 and 160 units/L.
Drugs that Affect Lipase Levels
- Drugs that may cause increased Lipase Levels include Bethanechol, Cholinergics, Codeine, Indomethacin, Meperidine, Methacholine, and Morphine.
- Drugs that may cause decreased Lipase Levels include Calcium Ions.
Causes of High Lipase Levels
- Pancreatic diseases (e.g., acute pancreatitis, chronic relapsing pancreatitis, pancreatic cancer, pancreatic pseudocyst): Lipase exists in the pancreatic cell and is released into the bloodstream when disease or injury affects the pancreas.
- Biliary diseases (e.g., acute cholecystitis, cholangitis, extrahepatic duct obstruction): Although the pathophysiology of these observations is not well understood, it is suspected that lipase exists inside the cells of the hepatobiliary system. Disease or injury of these tissues would cause the lipase to leak into the bloodstream and cause levels to be elevated.
- Renal failure: Lipase is excreted by the kidney. If excretion is poor, as in renal failure, lipase levels will rise.
- Intestinal diseases (e.g., bowel obstruction, infarction): Lipase exists in the mucosal cells lining the bowel (mostly in the duodenum). Injury through obstruction or ischemia will cause the cells to lyse. Lipase will leak into the bloodstream and cause levels to be elevated.
- Salivary gland inflammation or tumor: Like amylase, salivary glands contain lipase, although to a much lesser degree. Tumors, inflammation, or obstruction of salivary ducts will cause the cells to lyse. Lipase will leak into the bloodstream and cause levels to be elevated.
- Peptic ulcer disease: The pathophysiology of this observation is not well understood. Certainly, in perforated peptic disease the lipase in the gastrointestinal (GI) contents leaks out into the peritoneum, where it is picked up by the bloodstream. Lipase levels rise.