Parameter
| Biomarker | Amylase | Full name | Amylase | Molecular Type | Protein (hydrolytic enzymes, mainly including saliva amylase, pancreatic amylase) |
|---|---|---|---|---|---|
| Molecular Formula | Molecular Weight | Core Functional Dimensions | Acute pancreatitis severity diagnosis, a preliminary assessment, therapeutic effect monitoring | ||
| Disease | Acute pancreatitis (AP) | Disease Subtypes | / | ||
| Organ | Pancreas | Test Sample / Technology Platform | Serum/urine (biochemical analyzer, using enzyme rate method, colorimetry, etc.) | ||
| Pathobiological Mechanisms | Amylase is mainly synthesized by the pancreas (pancreatic amylase, which accounts for 40-50% of total serum amylase) and salivary glands (salivary amylase), and its core function is to hydrolyse starch to maltose in the digestive tract. During the onset of acute pancreatitis, the integrity of pancreatic cell membrane is destroyed due to inflammatory injury of pancreatic tissue, and pancreatic amylase is released into the blood in large amounts. At the same time, pancreatic duct obstruction or pancreatic juice reflux can also cause pancreatic amylase to enter the circulation through the damaged mucosa, which leads to the rapid increase of serum amylase level at 2-12 hours after the onset and reaches the peak at 24-48 hours. In addition, part of pancreatic amylase can be excreted in urine, and urinary amylase elevation occurs later but lasts longer (3-10 days) than serum, which can assist in the diagnosis of acute pancreatitis. The level of amylase elevation is not completely positively correlated with the severity of acute pancreatitis (mild edematous pancreatitis may be significantly increased, severe necrotic pancreatitis due to massive necrosis of pancreatic tissue, amylase synthesis is reduced, the level of amylase elevation is reduced or normal), but it is still a key indicator for early identification of acute pancreatitis. | ||||
| Clinical Availability Status | Routine clinical use: as the core biomarker for the diagnosis of acute pancreatitis, it has been included in the domestic and foreign guidelines for the diagnosis and treatment of acute pancreatitis (such as the Chinese Guidelines for the diagnosis and Treatment of acute pancreatitis (2021)). It is one of the preferred detection indicators for patients with clinically suspected acute pancreatitis, and its application is mature and popular. | ||||
| Notes and Dynamics | Amylase is a "classic index" for the early diagnosis of acute pancreatitis. It has the advantages of fast detection, low cost and high clinical popularity, which can quickly provide clinical diagnosis basis, especially suitable for rapid screening in the emergency setting. However, it should be noted that its specificity is limited: salivary gland diseases (such as mumps), gastrointestinal diseases (such as intestinal obstruction, gastric ulcer perforation), and renal insufficiency may lead to elevated serum amylase. It is necessary to combine the patient's abdominal pain symptoms and imaging examination (such as abdominal CT) to rule out non-pancreatic elevated serum amylase. At the same time, patients with severe acute pancreatitis may have a situation of "no elevation of amylase", which cannot be excluded by the normal level of amylase alone. It needs to be judged comprehensively with other indicators. | ||||