Serum amylase

Lab test abnormalities include the following ALT, AST, creatine kinase, hematuria, neutrophils, serum amylase, serum glucose, triglycerides, urine glucose. 

Monitoring of patients is advised with respect to clinical symptoms nausea, vomiting, abdominal pain) and abnormal laboratory values (elevated serum or urinary amylase, serum hpaae). The diagnosis can be confirmed by ultrasonography [124], a method (hat is useless if solely applied as a screening method before clinical or laboratory evidence for pancreatitis has been obtained [125]. 

B. Other useful laboratory studies include electrolytes, glucose, BUN, creatinine, calcium, ammonia, liver transaminases, bilirubin, prothrombin time (PT), amylase, serum osmolality and osmolar gap (see p 32 serum levels > 1500 mg/L may increase the osmolar gap by 10 mOsm/L or more), arterial blood gases or oximetry, and EGG monitoring. Valproic acid may cause a falsepositive urine ketone determination. 

In the Phadebas TM amylase test (72) (Pharmacia Labs) the substrate was a water insoluble cross-TTnked blue starch in tablet form which also contains some inert ingredients, sodium and potassium phosphate buffer salts and sodium chloride. This polymer was hydrolyzed by amylase into water soluble blue starch fragments. After centrifugation the absorbance of the blue supernatant was proportional to the activity of amylase present in the test samples. The day to day variation on a quality control serum had a coefficient of variation of 2.7% based on 30 days of data in our laboratory. The method is simple, reproducible and uses microquantities of serum. 

Amylase enters the blood largely via the lymphatics. An increase in hydrostatic pressure in the pancreatic ducts leads to a fairly prompt rise in the amylase concentration of the blood. Neither an increase in volume flow of pancreatic juice nor stimulation of pancreatic enzyme production will cause an increase in senm enzyme concentration. Elevation of intraductal pressure is the important determinant. Stimulation of flow in the face of obstruction can, however, augment the entry of amylase into the blood, as can disruption of acinar cells and ducts. A functional pancreas must be present for the serum amylase to rise. Serum amylase determination is indicated in acute pancreatitis in patients with acute abdominal pain where the clinical findings are not typical of other diseases such as appendicitis, cholecystitis, peptic ulcer, vascular disease or intestinal obstruction. In acute pancreatitis, the serum amylase starts to rise within a few hours simultaneously with the onset of symptoms and remains elevated for 2 to 3 days after which it returns to normal. The peak level is reached within 24 hours. Absence of increase in serum amylase in first 24 hours after the onset of symptoms is evidence against a diagnosis of acute pancreatitis (76). 

Various conditions such as perforated peptic ulcer, cholecystitis, common bile duct and intestinal obstruction, trauma to the abdomen inducing pancreatitis and ruptured ectopic pregnancy may cause an elevated serum amylase but the levels are usually not as high as those found in acute pancreatitis. Mumps and bacterial parotitis, which block the secretion of salivary amylase are associated with mild elevations of serum amylase. 

Opiates and other narcotics and analgesic drugs may unpre-dicatably elevate the serum amylase. The elevation may last up to 24 hours. Therefore it is important that blood for amylase determination be drawn before giving the patient analgesic drugs for pain. Elevation of the enzyme in peritoneal fluid is strong... 

The rate of urine amylase excretion is a sensitive reflection of the amylase released into the blood. The urine amylase remains abnormal 1-2 weeks after the serum returns to normal because the renal clearance of amylase rises 3-fold in acute pancreatitis and takes 1-2 weeks to return to normal. In pancreatitis, a number of investigators have reported a higher percentage of urinary amylase elevations, as contrasted with serum amylase elevations, particularly when the urinary amylase output over an interval is measured. Random urine collections for one, two and 24 hours are 792-4264 (2926 1074 S.D.) units per 24 hours. However, the wide range of normals make interpretation of results difficult. Of 107 patients with elevated serum or urine amylases, 16 were found to have a normal pancreas at operation (78). 

The study of the mechanism of urinary excretion of amylase and the amylase clearance has been the subject of many studies in recent years. Levitt et. al (79) studied the renal clearance of amylase in renal insufficiency, acute pancreatitis and macro-amylasemia. In acute pancreatitis, the kidney cleared amylase at a markedly increased rate. The ratio of the amylase clearance rate to the creatinine clearance rate (Cgm/Ccr) averaged 3 times normal early in the course of acute pancreatitis, and this elevation could persist after the serum amylase returned to normal. Comparison of an lase clearance to creatinine clearance was to minimize irrelevant changes due to variation in renal function. The increased clearance of amylase makes the urinary amylase a more sensitive indicator of pancreatitis. 

Shipe, J. R. and Savory, J. Kinetic nephlometric procedure for measurement of amylase activity in serum. Clin. Chem. (1972), 18, 1323-1325. 

Ceska, M. Birath, R. and Brown, B. A new and rapid method for the clinical determination of amylase activities in human serum and urine. Optimum conditions. 

Song, H. Tietz, N. W. and Tan, C. Usefulness of serum lipase, esterase and amylase estimation in the diagnosis of pancreatitis - a comparison. Clin. 

Diabetic patients have reduced antioxidant defences and suffer from an increased risk of free radical-mediated diseases such as coronary heart disease. EC has a pronounced insulin-like effect on erythrocyte membrane-bound acetylcholinesterase in type II diabetic patients (Rizvi and Zaid, 2001). Tea polyphenols were shown to possess anti-diabetic activity and to be effective both in the prevention and treatment of diabetes (Choi et al, 1998 Yang et al, 1999). The main mechanism by which tea polyphenols appear to lower serum glucose levels is via the inhibition of the activity of the starch digesting enzyme, amylase. Tea inhibits both salivary and intestinal amylase, so that starch is broken down more slowly and the rise in serum glucose is thus reduced. In addition, tea may affect the intestinal absorption of glucose. 

Determination of molecular mass of pectic enzymes The molecular mass were determined by gel filtration in a Sepharose CL-6B column (1,8 x 88cm) equilibrated and eluted with Tris-HCl 50 mM, pH 7,5 buffer, plus 100 mM KCl. Fractions (3,3 ml) were collected at a flow rate of 10 ml/h. Molecular mass markers were tyroglobulin (660 kDa) apoferritin (440 kDa) P-amylase (200 kDa) alcohol dehydrogenase (150 kDa) bovine serum albumin (66 kDa) and carbonic anhydrase (29 kDa). Urea-SDS-PAGE (7%) was carried out according to Swank and Munkres [12]. Molecular mass markers were myosin (205 kDa) p-galactosidase (116 kDa) phosphorylase b (97 kDa) bovine serum albumin (66 kDa), ovalbumin (45 kDa) and carbonic anhydrase (29 kDa). 

Figure 3. (A) Determination of molecular mass of pectic enzymes by gel filtration in Sepharose 6B. Molecular mass markers - tyroglobulin, 2- apoferritin, 3- p-amylase, 4-alcohol dehydrogenase, 5- bovine serum albumin, 6- carbonic anhydrase. (B) SDS-PAGE of pectolytic activities. Molecular mass markers 1- myosin, 2- p-galactosidase, 3- phosphorylase b, 4- bovine serum albumin, 5- ovalbumin, 6- carbonic anhydrase.

The serum amylase can be elevated three times the upper limit of normal within the first 12 hours of the onset of acute pancreatitis. The degree of elevation does not predict the severity of disease. 

Diagnosis of acute pancreatitis is based on the patient s history and presenting signs and symptoms. Evaluation of laboratory results, specifically the serum amylase and lipase, aids in diagnosis. Serum amylase is elevated early in the disease process but may return to normal within 12 hours.10 Serum lipase will remain elevated for days after the acute event and may lend itself more to the diagnosis depending on when the patient presents for evaluation.11... 

The goals of treatment for acute pancreatitis include (1) resolution of nausea, vomiting, abdominal pain, and fever (2) ability to tolerate oral intake (3) normalization of serum amylase, lipase, and white blood cell count and (4) resolution of abscess, pseudocyst, or fluid collection as measured by CT scan. 

Serum amylase and lipase levels are not usually elevated in chronic pancreatitis. 

A 16-year-old male treated for acme lymphocytic leukemia develops severe lumbar and abdominal pain His serum amylase is markedly elevated. Which of the following agents most likely caused these findings ... 

Hetastarch may cause elevations in serum amylase concentrations but does not cause pancreatitis. 

Acute pancreatitis (AP) is an inflammatory disorder of the pancreas characterized by severe pain in the upper abdomen and increased serum concentrations of pancreatic lipase and amylase. 

The serum amylase concentration usually rises 4 to 8 hours after symptom onset, peaks at 24 hours, and returns to normal over the next 8 to 14 days. Serum amylase concentrations greater than three times the upper limit of normal are highly suggestive of AP. 

Serum lipase is specific to the pancreas, and concentrations are usually elevated. The increases persist longer than serum amylase elevations and can be detected after the amylase has returned to normal. 

Analgesics are given to reduce abdominal pain. In the past, parenteral meperidine (50 to 100 mg) every 3 to 4 hours was usually used because it causes less spasm of the sphincter of Oddi than other opioids. Meperidine is used less frequently today because it is not as effective as other opioids and is contraindicated in renal failure. Parenteral morphine is sometimes used, but it is thought to cause spasm of the sphincter of Oddi, increases in serum amylase and, rarely, pancreatitis. Hydromorphone may also be... 

Serum amylase and lipase concentrations usually remain normal unless the pancreatic duct is blocked or a pseudocyst is present. 

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