Pancreatic Functions and Acute pancreatitis
Sample
- The serum of the patient is required.
- The serum for lipase is stable at room temperature for several days if there is no bacterial contamination.
- Avoid contamination with saliva.
- Lipemic serum, EDTA, Citrate, and fluoride decrease the Amylase quantity.
- The serum for amylase is stable at room temperature for 7 days and at 4 °C for one month.
- Urine: Amylase is unstable in acidic urine. Adjust the pH to the alkaline range before storage.
- It can take one hour or 24 hours of a urine sample.
- Store at 4 °C.
Advised Tests are:
- The following blood tests are done to diagnose the pancreatic disease:
- Serum amylase
- Serum lipase
- Acute pancreatitis, there is the elevation of amylase and lipase.
- Amylase is less specific for pancreatitis than lipase because amylase is also produced by the salivary glands.
Pathophysiology
- The pancreas weighs 70 to 105 grams and is located in the curve of the duodenum.
- The pancreas is the gland with exocrine and endocrine function play a very important role in the digestive function.
- It produces pancreatic juice rich in bicarbonate and digestive enzymes.
- Bicarbonate neutralizes acid coming from the stomach.
- The pancreas consists of:
- Endocrine tissue (Islets of Langerhans is small 0.1 to 0.15 mm in D).
- Its secretion goes directly into blood circulation. It has no link with the ducts.
- Beta cells are the most numerous which produce insulin.
- Insulin is a small protein with a molecular weight of 6000.
- Insulin is a potent hormone that promotes glucose uptake and glycogen storage, triglycerides synthesis, and protein synthesis.
- It is produced as proinsulin which is inactive.
- Insulin is a small protein with a molecular weight of 6000.
- Endocrine tissue (Islets of Langerhans is small 0.1 to 0.15 mm in D).
-
-
-
-
-
- This is known as an antidiabetic hormone.
- Insulin normal value is 860 pg/mL and it does not exceed this value in a normal person.
- While this will increase in the adenoma of the pancreas (Insulinoma).
-
-
- Alpha cells produce glucagon.
- Glucagon is a polypeptide hormone produced by alpha cells in the islets cells.
- Glucagon raises the blood sugar by activating the liver phosphorylase, which will break down glycogen.
- Glucagon stimulates the hydrolysis of triglycerides in adipose tissue to fatty acids and glycerol.
- Glucagon also reduces the secretory response of the parietal cells to all the stimuli except the histamine.
- Glucagon is a polypeptide hormone produced by alpha cells in the islets cells.
-
-
- Exocrine tissue. This produces the digestive enzymes from the acinar cells of the pancreas.
- Exocrine enzymes are:
- Digestive enzymes are:
- Amylase is digestive enzymes.
- Amylase present in the human tissue is α- amylase.
- Digestive enzymes are:
-
-
- Amylase breaks down the body starch.
-
-
-
- Lipase helps to digest fats.
- This is a glycoprotein with a molecular weight of 54000 and an isoelectric point of about 5.8.
- Lipase concentration in the pancreas is about 100 times greater than other tissue.
- Lipase helps to digest fats.
-
-
- Proteolytic enzymes are:
- Trypsin is a main proteolytic enzyme.
- Chymotrypsin secreted as chymotrypsinogen A and B.
- Collagenase digest collagen and is the enzyme that initiates destruction in necrotizing pancreatitis.
- Elastase specially digests elastin which is the most resistant of all body proteins to lytic agents.
- Peptidases are:
- Carboxypeptidase removes amino acids one by one from the carboxyl ends of the peptide chain.
- Aminopeptidase removes the amino acids from the end of peptide chains having a free amino group.
- Nucleases are:
- Ribonuclease.
- Deoxyribonuclease hydrolyzes the respective nucleic acid.
- Proteolytic enzymes are:
- Alcoholics will raise the level of amylase which is salivary gland origin.
- Lipase is technically difficult to measure. But Lipase is not cleared in urine so remains in the blood circulation even amylase becomes normal.
Normal values
Source 1
Lipase serum
- <200 U/L (with triolein)
- <160 U/L (with olive oil)
- With RIA = <112 µg/L
- To convert into SI unit x 0.017 = µKat/L
Amylase serum
- Newborn 2 to 4 days = 5 to 65 U/L
- Adult = 27 to 131 U/L
- 60 to 90 year = 24 to 151 U/L
- To convert into SI unit x 0.017 = µKat/L
Amylase urine
- 1 to 17 U/hour (Beckman)
- 170 to 2000 U/L (Phadebas)
- 5 to 27 U/hour (Abbott TDx)
- The values vary from a different methodology.
Source 2
Amylase serum
- 60 to 120 Somogyi units/dL (30 to 220 units/L) .
- Newborn = 6 to 65 units/L
Urine amylase 24 hours
- up to 500 Somogyi units.
Lipase serum
- 0 to 160 units/L
(Values vary according to the method).
- Critical value = More than the three times of the normal.
Symptoms of acute Pancreatitis are:
- Acute pancreatitis is due to the blockage of pancreatic ducts or direct injury to the pancreatic tissue by:
- Toxin.
- Inflammation.
- Trauma.
- Impaired blood flow to the pancreas.
- Loss of appetite.
- Nausea and vomiting.
- Severe abdominal pain (this is an excruciating pain).
- Back pain.
Diagnosis of acute pancreatitis:
- The first few days check amylase at least twice a day.
- >500 Somogyi units favor acute pancreatitis.
- The peak is short and maybe missed.
Lipase is increased in:
- Acute Pancreatitis.
- Pancreatic cyst or pseudocyst.
- Pancreatic cancers.
- Chronic pancreatitis
- peptic ulcer with perforation of the pancreas.
- Gastric cancer with perforation of the pancreas.
- Acute cholecystitis.
- Certain drugs like deoxycholate, and glycocholate.
- Chronic liver disease
Amylase is increased in:
- In Acute pancreatitis, it is increased 4 to 6 times normal.
- The increase occurs in 4 to 8 hours of the onset.
- Remain elevated till the cause is removed.
- Chronic pancreatitis initially, there is a mild increase and later on, decrease due to damage to the pancreas.
- Increased in pancreatic duct obstruction
- Pancreatic cancers.