Anemia-Related Medical Terminology Explained
Basic anemia-related medical terminology is a group of common words that pertain to a low red blood cell count and the different causes of it. It aids in the understanding of much of the information on the topic. It is also a valuable tool for increasing health literacy in this area. It makes for improved communication in health care, better understanding of health care and informed health-care decision making.
Anisocytosis – Is a difference in the size of an individual’s red blood cells. It is apparent with a microscope or based on an increased RDW. It can result from various disorders that affect erythrocyte production.
Ferritin – Is a protein complex which is the main storage vehicle for iron. The testing of it confirms iron deficiency when it is low. It is not a reliable indicator of iron status when it is normal or elevated though. It is present primarily in the liver, spleen and the membranes lining the intestines.
Folate – Is a generic term for any of the naturally occurring forms of water soluble vitamin B9 which is required for several biologic functions including the production of red blood cells. It is a common misconception that folate and folic acid are interchangeable terms. Even though they are both forms of vitamin B9 there are some differences between the two. Folic acid is chemically similar to folate but is in an oxidized state. That means it is folate which has lost some of its electrons.
Neither compound is inherently ready for use by the body. They must both undergo conversion to a biologically active form – tetrahydrofolate (THF). The conversion of folate occurs in the cells lining the small intestine. The site of conversion of folic acid is the liver. Folic acid is synthetic (made in the laboratory) and is the form of vitamin B9 which is in supplements. Active folate on the other hand is present in a healthy diet. It is abundant in such foods as leafy green vegetables, peas, some beans and whole grain.
Hypochromia – Is a lower than normal amount of hemoglobin in red blood cells. Consequently it causes the cells to have less color than normal and appear pale when viewed under a microscope.
– Hypochromic – adj.
Iron – Is a chemical element and an essential component of the heme portion of hemoglobin. Thus, it is a key component of red blood cell production and is a chief factor involved in a low red blood count when it is lacking.
MCHC (Mean corpuscular hemoglobin concentration) (Mean cell hemoglobin concentration) – Is the average amount by weight of hemoglobin per red blood cell in a sample of blood. It is the total mass of hemoglobin divided by the number of red blood cells in the volume of blood. Its expression is in grams per 100 milliliters (grams per deciliter). When it is lower than normal hypochromia exists. It is the basis of a hypochromic anemia.
MCV (Mean corpuscular volume) (Mean cell volume) – Is the average volume of red blood cells in a given sample of blood. It is a calculation made by multiplying the volume of blood in a sample by the proportion that is cellular (hematocrit) and then dividing by the number of red blood cells in that volume (red blood cell count). Its unit of expression is femoliters (fL or 1015Liter). It is an important clue of the type of anemia. It reflects normocytosis, microcytosis or macrocytosis.
Microcytosis – Is a state in which circulating red blood cells are smaller than normal. The MCV is less than 80 fL. It is characteristic of iron deficiency anemia and might be present with anemia of chronic disease.
– Microcytic – adj.
Poikilocytosis – Is the presence of RBCs with abnormal shapes in blood.
RDW (Red cell distribution width) – Is a test which measures the variation in the size of red blood cells in a sample of blood. It is based on the fact that blood contains red blood cells of different ages and that younger cells are larger in size. Conditions that cause a more rapid production of cells, microcytosis and macrocytosis are some of the factors that affect it. The normal range is from 10.2% to 14.5%.
Reticulocytes – Are immature RBCs that mature in the bone marrow. They circulate in the blood for about a day before fully developing into RBCs. They typically comprise ~1% of RBCs. Their percentage is higher when the body is attempting to compensate for a drop in the red blood cell count.
Sideroblast – Is a red blood cell precursor in the bone marrow with iron granules in its cytoplasm. The iron is visible with a microscope and staining of a bone marrow specimen with Prussian blue. When the iron surrounds the nucleus of the cell because of its location in mitochondria it is termed a ringed sideroblast. It is the hallmark of siderblastic anemia.
Total iron binding capacity (TIBC) – Is a blood test to determine if there is a deficiency or excess of iron in the blood. It measures the maximum quantity of iron the blood can carry bound to transferrin.
Transferrin – Is the protein which carries iron in blood. The percent saturation of it with iron along with iron and TIBC tests can distinguish between iron deficiency, anemia of chronic disease, pregnancy, or the use of hormonal contraception in the absence of iron deficiency.
Vitamin B12 (cobalamin) – Is a vitamin in the B family which is important for the making of red blood cells and healthy nerve tissues.