Macroamylasemia defines the presence of macroamylase in the blood.
Macroamylasemia is a rare disorder, where amylase (a type of protein) is bound to other macromolecules (such as immunoglobulins and polysaccharides) to form a complex called macroamylase.
Because of the size of the forming complexes, the renal excretion is reduced, and the amylase level in the blood increases.
Macroamylasemia is not considered the consequence of any disease.
However, several diseases are frequently associated with macroamylasemia such as:
The prevalence of macroamylasemia is about the 0.5-2% of general population. It is more common in elderly people (aged 50-70 years).
Macroamylasemia is a condition where no symptoms related are present.
In case of macroamylasemia the amylase level in the blood is higher than normal. However, the amylase excreted in the urine will be reduced.
A high level of amylase in the blood normally suggests a pancreas disorder, but sometimes there is no problem related to the pancreas and it is due to macroamylasemia.
If the possibility of suffering macroamylasemia is being considered, the amylase-to-creatinine clearance ratio (ACCR) is very helpful.
The ACCR ratio is measured by the following formula:
ACCR = (Amylase in urine x Creatinine in serum x 100) / (Amylase in serum x Creatinine in urine)
In case of macroamylasemia the ACCR ratio is reduced because the amylase in serum is high and the amylase excreted in urine is low. An ACCR ratio less than 1 percent on a 24-hour collection strongly supports the diagnosis of macroamylasemia.
In case of pancreatitis the level of amylase in the blood is also high, but the ACCR ratio is also high with ACCR ratio values between 1% to 4%.
Macroamylasemia is a benign condition that does not require any treatment.
In patients with celiac disease, sometimes, macroamylasemia may resolve following a gluten-free diet.