The Clinical Significance of Macrocytosis

Abstract

The cause of macrocytosis (mean corpuscular volume (MCV) .gtoreq. 105 fl) was investigated over 16 mo. in 70 known cases. By simple laboratory investigations the cause of elevated MCV was found in > 90% of the cases. Vitamin B12 or folic acid deficiency was found in 27 patients, alcohol abuse in 19, chronic persistent hepatitis in 2, hematological (pre-)malignancy in 9, hemolysis in 4, hypothyroidism in 2 and a drug effect in 1 patient. In 6 cases the elevated MCV could not be explained. Macrocytosis, a frequent finding that is not related to the Hb concentration, is an indicator of serious pathology. The MCV level can be used to differentiate between the diagnostic categories. Only 21 patients (30%) had megaloblastic erythropoiesis that was difficult to recognize in the peripheral blood. Among the findings at routine laboratory investigations an elevated MCV may be the only indicator of vitamin deficiency, preleukemia or alcoholism.