What Is Macroamylasemia?
Macroamylasemia is an acquired enzyme disorder that causes elevated levels of the enzyme amylase (hyperamylasaemia) in the bloodstream. It is characterized by altered amylase molecules that have become abnormally bound with plasma proteins in the bloodstream, commonly IgG (immunoglobulin G) and/or IgA (immunoglobulin A).
The resulting molecule is too large to be properly filtered by the kidneys and excreted in the urine as would be normal unbound amylase, causing sustained elevation of amylase levels in the plasma.
With normal kidney function, a hyperamylasemia without an increase in urine amylase suggests the diagnosis of macroamylasemia, and is confirmed by identifying the macromolecular components.1
Amylase is a an enzyme produced by the pancreas and the parotid glands to digest starch in the diet. Comparatively small amounts are also produced by other organs.
Q: How do the pancreas and parotid glands deliver their amylase for digestion of starch?
A: The parotid glands deliver their amylase into the mouth. The action of amylase in the mouth starts the breakdown of starch as it is chewed and moistened with saliva.
After the starchy food is liquified in the stomach, the mass empties into the duodenum. Here pancreatic amylase is delivered through the common bile duct into the duodenum where it turns starch into maltose sugar. The next step to final digestion of starch is carried out by enzymes in the small intestinal lining that split maltose into its component sugar which is glucose.
Distinquishing macroamylasemia from hyperamylasemia due to pancreatic disease is necessary to prevent needless treatment and investigation for pancreatitis.2
What Is Macroamylasemia In Celiac Disease and/or Gluten Sensitivity?
Hello. The following content is for subscribers.
Already a subscriber? Please login below…
- Torrent Vernetta A, Segarra Cantón O, Soler Palacín P, Segura Cardona RM, Infante Pina D. Macroamylasaemia in paediatrics. An Pediatr (Barc). 2008 Nov;69(5):439-41.
- Isham CA, Ridgeway NA, Hedrick R, Cate JC 4th. Screening for macroamylase in a community hospital. Clin Chem. 1984 May;30(5):741-2.