What is Hypochromic Anemia?

Hypochromic anemia is a general term for types of anemia that result in the red blood cells of the body having less color than usual. The cells are paler because they have less of the oxygen-carrying hemoglobin pigment than normal. The most common cause of hypochromic anemia is iron deficiency, but it can also be caused by lead poisoning or a condition known as thalassemia.

Anemic red blood cells are identified as hypochromic by looking at blood samples under a microscope. Red blood cell (RBC) analyzes are common tests for the diagnosis of anemia, and such blood tests are generally made up of three specific sections. These are the mean corpuscular volume (MCV) test, which measures average size of the red blood cells; the mean corpuscular hemoglobin (MCH) test, which measures the amount of hemoglobin per red blood cell; and the mean corpuscular hemoglobin concentration (MCHC) test, which measures the amount of hemoglobin relative to the average red blood cell size.

Hypochromic cells have less than 27 picograms of hemoglobin per cell. As well as being hypochromic, anemic cells can also be microcytic, which means the cells are smaller than usual. While hypochromic cells are paler than normal, hyperchromic cells have higher color than usual when viewed through a microscope and normochromic cells are within normal color limits.

A patient becomes iron deficient and her red blood cells become hypochromic in one of four ways. She may not be taking in enough iron from her diet, she may not be able to absorb dietary iron efficiently, she may be losing blood, or she may be pregnant and her fetus is taking too much iron from her own stores. She can lose blood through heavy periods or through chronic gastrointestinal bleeding. Sudden blood loss is not a cause of hypochromic anemia, because the red blood cells of patients who have had a sudden blood loss are of a normal color.

A patient with hypochromic anemia caused by iron deficiency may suffer from fatigue, pale skin, weakness, dizziness, shortness of breath, headaches, brittle nails, irregular heartbeat or may be more irritable than usual. She may have a poor appetite and have cravings for non-food items such as dirt or ice. She may also suffer from an unusual tingling feeling in her legs known as restless legs syndrome.

Thalassemic patients can also have hypochromic red blood cells. Thalassemia is an inherited disease that causes sufferers to make an abnormal form of the hemoglobin pigment. The abnormal hemoglobin causes destruction of some red blood cells and causes hypochromia under a microscope.