Hyperamylasemia

Excerpt

Hyperamylasemia refers to an elevated serum amylase level beyond the upper limit of normal (normal range is typically 30 U/L to 110 U/L). Amylase is one of the digestive enzymes that is designed to act intracellularly. Its function is to break down starch into smaller carbohydrate units yielding monosaccharides in the end. The process is completed using hydrolysis of the glycoside bonds causing the release of maltose and oligosaccharides. Serum amylase is mainly released from the pancreas (40%-45%) and salivary glands (55%-60%). It is an enzyme produced in two isoforms, P-type amylase and S-type amylase. P-type amylase is secreted from the pancreas, while S-type amylase is secreted from the salivary glands. The amylase clearance occurs through the kidney (25%) and the reticuloendothelial system (75%).

Serum amylase is not the most appropriate test for diagnosing pancreatitis as it lacks specificity. Although it is increased in around 75% of cases of pancreatitis, however, serum amylase may be within the normal range, even in a case of massive pancreatic necrosis.