Amylase in the blood and urine
Last reviewed: 23.04.2024
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Reference values (norm) of alpha amylase activity: in blood serum - 25-220 IU / l; in the urine 10-490 IU / l.
Alpha amylase belongs to the group of hydrolases that catalyze the hydrolysis of polysaccharides, including starch and glycogen, to simple mono- and disaccharides. The pancreatic and salivary glands are the richest in amylase. Amylase is secreted into the blood mainly from these organs. Human blood plasma contains two types of α-amylases: the pancreatic (beta-type) produced by the pancreas, and the salivary (S-type) produced by the salivary glands.
Under physiological conditions, the activity of this enzyme in the blood serum is represented by pancreatic amylase by 40%, by 60% by salivary amylase.
Determination of alpha amylase activity is important in the diagnosis of pancreatic diseases. Increase in alpha serum amylase activity in 2 times or more should be regarded as a symptom of pancreatic lesion. A small hyperamilazemia gives reason to suspect pancreatic pathology, but sometimes it is possible with diseases of other organs.
With urine, there is mainly beta-type alpha amylase, which is considered one of the reasons for the more informative urine amylase than blood serum in terms of assessing the functional state of the pancreas. It is believed that 65% of the enzyme activity in urine is due to pancreatic amylase. This explains the fact that in acute pancreatitis it is it that increases in serum (up to 89%) and especially in urine (up to 92%), without changes in salivary gland amylase.