Macroamylasemia

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

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

Most people with macroamylasemia do not have a serious disease that is causing it, but the condition has been associated with:

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

Symptoms
Macroamylasemia does not cause symptoms.

Exams and Tests
A blood test will show high levels of amylase. However, macroamylasemia can look similar to acute pancreatitis, which also causes high levels of amylase in the blood.

Measuring amylase levels in the urine can help tell macroamylasemia apart from acute pancreatitis. Urine levels of amylase are low in people with macroamylasemia, but high in patients with acute pancreatitis.

References
Forsmark CE. Pancreatitis. In: Goldman L, Schafer AI, eds. Cecil Medicine . 24th ed. Philadelphia, Pa: Saunders Elsevier; 2011:chap 146.

Update Date: 2/19/2012
David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M. Health Solutions, Ebix, Inc.