Final answer:
The most common hematologic abnormality in chronic alcoholics is macrocytosis, which is characterized by the presence of larger than normal red blood cells and is detected by measuring the mean corpuscle volume (MCV).
Step-by-step explanation:
The most common hematologic abnormality seen in the chronic alcoholic is macrocytosis. Macrocytosis refers to the presence of abnormally large red blood cells (RBCs), which can be detected through a common test called the mean corpuscle volume (MCV). Chronic alcoholism can lead to altered hematopoiesis resulting in macrocytic anemia. Unlike other abnormalities like leukocytosis (excessive leukocyte proliferation), leukopenia (below-normal production of leukocytes), or thrombocytosis (abnormally high platelet counts), macrocytosis is more frequently associated with chronic alcohol abuse. It is characterized by an increased MCV, where the RBCs are larger than normal (macrocytic).