Macroamylasemia

Definition

Macroamylasemia is the presence of an abnormal substance called macroamylase in the blood.

Causes, incidence, and risk factors

Macroamylase is a molecule that consists of an enzyme, called amylase, which is attached to a protein. Because it is relatively large, macroamylase is filtered very slowly from the blood by the kidneys.

Macroamylasemia has been associated with:

• Celiac disease
• Lymphoma
• HIV infection
• Monoclonal gammopathy
• Rheumatoid arthritis
• Ulcerative colitis

Symptoms

Macroamylasemia does not cause symptoms.

Signs and tests

A blood test will show high levels of amylase. However, macroamylasemia can be confused with acute pancreatitis, which also causes high levels of amylase in the blood.

Macroamylasemia can be diagnosed by measuring amylase levels in the urine. Urine levels of amylase would be low. (Urine amylase levels are high in patients with acute pancreatitis.)

References

Owyang C. Pancreatitis. In: Goldman L, Ausiello D, eds. Cecil Medicine. 23rd ed. Philadelphia, Pa: Saunders Elsevier; 2007:chap 147.