TEST CATALOG ORDERING & RESULTS SPECIMEN HANDLING CUSTOMER SERVICE EDUCATION & INSIGHTS
Test Catalog

Test ID: AMBF    
Amylase, Body Fluid

Useful For Suggests clinical disorders or settings where the test may be helpful

Evaluation of patients with a pathological accumulation of fluid to determine whether pancreatic inflammation, pancreatic fistula, or esophageal rupture may be contributing

 

Aiding in the diagnosis of pancreatitis

Clinical Information Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test

Pleural fluid:

Amylase-rich pleural effusions are commonly associated with pancreatitis, esophageal rupture, malignancy, pneumonia, and liver cirrhosis.(1) Pleural fluid amylase measurement is not routinely indicated though may help to narrow the differential due to these causes. Results should be interpreted in conjunction with serum measurement usually as a ratio of pleural fluid to serum amylase. The ratio of pleural fluid to serum amylase in effusions caused by pancreatic disease is much higher (mean + or - SD = 18 + or - 6.3) versus non-pancreatic disease (4.8 + or - 1.3) (P = 0.003).(2) Isoform analysis revealed that pancreatic amylase is diagnostic of pancreatitis-related pleural effusions, whereas salivary amylase isoforms are more often associated with esophageal rupture and malignancy.(3)

 

Peritoneal fluid:

The digestive enzymes amylase and lipase can be measured in the identification of pancreatic fluid in the peritoneal cavity. Concentrations are expected to be elevated and at least several-fold times higher in fluid of pancreatic origin compared to simultaneous concentrations in serum.(4) In contrast, amylase concentration in ascites of non-pancreatic origin was approximately half the plasma value.(5)

 

Drain fluid:

Amylase might be measured in a drain fluid to aid in the identification of internal pancreatic fistulas due to chronic pancreatitis or formation of a fistula after surgery.(6,7) Comparison to serum concentrations is recommended with elevations several-fold higher than blood being suggestive of the presence of pancreatic fluid in the drained cavity.

Reference Values Describes reference intervals and additional information for interpretation of test results. May include intervals based on age and sex when appropriate. Intervals are Mayo-derived, unless otherwise designated. If an interpretive report is provided, the reference value field will state this.

An interpretive report will be provided

Interpretation Provides information to assist in interpretation of the test results

Peritoneal and drain fluid amylase activity in non-pancreatic peritoneal fluid is often less than or equal to the serum amylase activity. Ascites associated with pancreatitis typically has amylase activity at least 5-fold greater than serum.(1)

 

Normal pleural fluid amylase activity is typically less than the upper limit of normal serum amylase and has a ratio of pleural fluid amylase to serum amylase ratio less than 1.0.(3)

 

All Other Fluids: Body fluid amylase activity may become elevated due to the presence of pancreatitis, esophageal rupture, or amylase producing neoplasms. Results should be interpreted in conjunction with serum amylase and other clinical findings.

Cautions Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances

In very rare cases, gammopathy, in particular type IgM (Waldenstrom macroglobulinemia), may cause unreliable results.

 

Icodextrin-based drugs may lead to decreased amylase results.

Clinical Reference Recommendations for in-depth reading of a clinical nature

1. Burgess LJ: Biochemical analysis of pleural, peritoneal and pericardial effusions. Clin Chim Acta. 2004;343:61-84

2. Joseph J, Viney S, Beck P, et al: A prospective study of amylase-rich pleural effusions with special reference to amylase isoenzyme analysis. Chest. 1992;102:1455-1459

3. Sahn SA: Getting the most from pleural fluid analysis. Respirology. 2012;17:270-277

4. Robert JH, Meyer P, Rohner A: Can serum and peritoneal amylase and lipase determinations help in the early prognosis of acute pancreatitis? Ann Surg. 1986;203:163-168

5. Runyon BA: Amylase levels in ascitic fluid. J Clin Gastroenterol. 1987;9:172-174

6. Lipsett PA, Cameron JL: Internal pancreatic fistula. Am J Surg. 1992;163:216-220

7. Kaman L, Behera A, Singh R, et al: Internal pancreatic fistulas with pancreatic ascites and pancreatic pleural effusions: recognition and management. ANZ J Surg. 2001;71:221-225

8. Nandakumar V, Dolan C, Baumann NA, Block DR: Effect of pH on the quantification of body fluid analytes for clinical diagnostic testing. Am J Clin Path. 2019 Oct;152(S1): S10-S11