Macrocytosis


Macrocytosis is the enlargement of red blood cells with near-constant hemoglobin concentration, and is defined by a mean corpuscular volume of greater than 100 femtolitres. The enlarged erythrocytes are called macrocytes or megalocytes. As a symptom its cause may be relatively benign and need no treatment or it may indicate a serious underlying illness.

Causes

In humans, most commonly the cause is bone marrow dysplasia secondary to alcohol abuse and chronic alcoholism.
Poor absorption of vitamin B12 in the digestive tract can also cause macrocytosis.
Gastrointestinal diseases that may cause macrocytosis include celiac disease and Crohn's disease.
Other causes may include:
No complications arise from macrocytosis itself and a prognosis will be determined from its cause.