Amylase Isoenzymes (Macro Amylase, Amylase Electrophoresis), Plasma

Diagnostic Use

The amylase enzymes are a group of hydrolases that degrade complex carbohydrates (starches) into simple sugars. The pancreas and salivary glands have amylase concentrations that are orders of magnitude greater than any other tissue. These two amylase isoenzymes, pancreatic and salivary, are present in plasma. Hyperamylasemia can result from either increased rate of release of amylase into blood or decreased metabolic clearance of the enzyme (i.e., macroamylase).
Macroamylasemia
This is a benign condition in which normal amylase forms macromolecular complexes with immunoglobulins (IgG, IgM) or it exists as a large polymeric aggregate, resulting in a variety of “macroamylases”, which, because of their large molecular size, are not excreted by the kidney. This results in elevated amylase levels in the serum. Its clinical significance lies in the fact that the hyperamylasemia or macroamylasemia may lead to misinterpretations in the differential diagnosis of abdominal distress. Macroamylasemia accounts for 2.5% of hyperamylasemic conditions. One per cent of healthy subjects have macroamylasemia. It requires no treatment and, in fact, may be transient. In this condition, the amylase/creatinine clearance ratio described below is usually <1% (normal 1-5%), and the urine amylase is usually low.

Department

Specialist Biochemistry

Delphic Registration Code

AMEP

Laboratory Handling

Separating

Aliquot to Specialist Biochemistry - Freezer

Laboratory

Gross haemolysis reject

Test Adds

Refrigerated (preferred) 30 days, frozen 30 days

Synonyms

Amylase Electrophoresis
Amylase Macro
Macro Amylase

Turnaround Time

14 days

Test Code

7964