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Test ID: RAMSU Amylase, Random, Urine

Reporting Name

Amylase, Random, U

Useful For

Assessment of acute rejection of bladder-drained pancreas transplants


Diagnoses of acute pancreatitis

Specimen Type


Specimen Required

Container/Tube: Plastic, 5-mL tube (T465)

Specimen Volume: 5 mL

Collection Instructions:

1. Collect a random urine specimen.

2. No preservative.

Specimen Minimum Volume

1 mL

Specimen Stability Information

Specimen Type Temperature Time Special Container
Urine Refrigerated (preferred) 7 days
  Frozen  7 days

Reference Values

No established reference values

Day(s) and Time(s) Performed

Monday through Sunday; Continuously

Test Classification

This test has been cleared, approved or is exempt by the U.S. Food and Drug Administration and is used per manufacturer's instructions. Performance characteristics were verified by Mayo Clinic in a manner consistent with CLIA requirements.

CPT Code Information


LOINC Code Information

Test ID Test Order Name Order LOINC Value
RAMSU Amylase, Random, U 1799-6


Result ID Test Result Name Result LOINC Value
RAMSU Amylase, Random, U 1799-6

Clinical Information

Amylases are enzymes that hydrolyze complex carbohydrates. They are produced by a number of organs and tissues, predominantly the exocrine pancreas (P-type amylase) and salivary glands (S-type amylase). Plasma amylases are of relatively low molecular weight for an enzyme (55,000 to 60,000 daltons) and enter the urine through glomerular filtration. Conditions that cause increased entry of amylase into plasma (eg, acute pancreatitis) will thus result in increased urinary excretion of amylase. Urinary amylase is therefore sometimes used in the diagnosis of acute pancreatitis. However, the rate of urinary amylase excretion appears to be less sensitive than plasma markers, and is not specific for the diagnosis of acute pancreatitis.


Similar to other low molecular weight proteins filtered by glomeruli, amylases are reabsorbed to an extent by the proximal tubule. Thus, conditions associated with increased production and glomerular filtration of other low molecular weight proteins that compete with tubular reabsorption of amylase, or conditions of proximal tubular injury may increase urinary amylase excretion. Also, a number of disorders other than acute pancreatitis may cause increases in plasma amylase concentrations and consequent increases in urinary amylase excretion. These conditions include burns, ketoacidosis, myeloma, light-chain proteinuria, march hemoglobinuria, acute appendicitis, intestinal perforation, and following extracorporeal circulation.


Urinary amylase clearance is increased about 3-fold for 1 to 2 weeks in patients with acute pancreatitis. A value > 550 U/L has been reported as 62% sensitive and 97% specific for acute pancreatitis (3), while a value > 2000 U/L has been reported as 62% sensitive and 97% specific for acute pancreatitis (4).


Quantitation of urinary amylase excretion is also useful in monitoring for rejection following pancreas transplantation. The duodenal cuffs of donor pancreases are often surgically anastomosed to the recipient's bladder at the time of pancreas transplantation, allowing for drainage of exocrine pancreas fluid into the bladder. In pancreatic rejection, urinary amylase excretion decreases.


In patients with pancreas transplants that drain into the urinary system, a drop in urinary amylase of more than 25% from that patient’s baseline value can indicate acute rejection (5). In this situation, collecting a timed urine sample and expressing the urinary amylase level as Units excreted/hr might reduce variability and improve test performance (6).


Decreases in urinary amylase excretion of greater than 30% to 50%, relative to baseline values, may be associated with acute pancreas allograft rejection. Because there is large day-to-day variability in urinary amylase excretion following pancreas transplantation, if a significant decrease is noted, it should be confirmed by a second collection. There is also large inter-individual variability in urinary amylase excretion among pancreas transplant recipients. Acute rejection is usually not established solely by changes in urinary amylase excretion, but by tissue biopsy. 

Levels are elevated in acute pancreatitis (but with poor sensitivity and specificity).

Clinical Reference

1. Tietz Textbook of Clinical Chemistry. Third edition. Edited by CA Burtis, ER Ashwood. Philadelphia, WB Saunders Co., 1999, pp 689-698

2. Munn SR, Engen DE, Barr D, et al: Differential diagnosis of hypo-amylasuria in pancreas allograft recipients with urinary exocrine drainage. Transplantation 1990;49:359-362

3. Kemppainen EA, Hedstrom JI, Puolakkainen PA, et al: Rapid measurement of urinary trypsinogen-2 as a screening test for acute pancreatitis. N Engl J Med 1997;336:1788-1793

4. Treacy J, Williams A, Bais R, et al: Evaluation of amylase and lipase in the diagnosis of acute pancreatitis. ANZ Journal of Surgery 2001;71:577-582

5. Klassen DK, Hoen-Saric EW, Weir MR, et al: Isolated pancreas rejection in combined kidney pancreas transplantation. Transplantation 1996;61:974-977

6. Benedetti E, Najaran JS, Gruessener AC, et al: Correlation between cystoscopic biopsy results and hypoamylasuria in bladder-drained pancreas transplants. Surgery 1995;118:864-872

Analytic Time

1 day

Method Name

Enzymatic Rate


If not ordering electronically, complete, print, and send a Gastroenterology and Hepatology Client Test Request (T728) with the specimen.

Mayo Clinic Laboratories | Gastroenterology Catalog Additional Information: