Overview
What is microcytosis?
Microcytosis means you have smaller-than-normal red blood cells. It’s a description, not an official diagnosis. You may learn that you have microcytosis after routine blood work, called a complete blood count (CBC). A CBC is a test that provides information about your health by assessing your blood cells.

One value on a CBC is called mean corpuscular volume (MCV). MCV is the average size of your red blood cells. For adults, microcytosis means that the MCV is less than 80 femtoliters (fL).

Microcytosis is often a sign of microcytic anemia. With microcytic anemia, red blood cells don’t have enough hemoglobin. Hemoglobin is an essential protein that allows red blood cells to transport oxygen throughout your body.

How common is microcytosis?
Microcytic anemia is the most common form of anemia in adults and children.

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Symptoms and Causes
What are the symptoms of microcytosis?
Often, there aren’t any symptoms, and the only sign of microcytosis is a low MCV value.

When symptoms do occur, they’re the same as with microcytic anemia. They include:

Fatigue.
Pale skin.
Shortness of breath.
Rapid heartbeat.
Pica (occurs only if the microcytosis is caused by an iron deficiency).
You may also experience symptoms associated with what’s causing microcytosis.

What causes microcytosis?
Microcytosis most often occurs when your body’s not getting enough iron. This is called iron-deficiency anemia. Iron is an essential ingredient in hemoglobin.

Environmental factors, medical conditions (inherited and acquired) and certain behaviors can also lead to microcytosis.

The most common causes of microcytosis include:

Iron deficiency: Nutritional deficiencies can prevent you from getting enough iron in your diet. Conditions like celiac disease and H. pylori infection can prevent your body from absorbing iron, as can gastric bypass surgery. Or you may have an iron deficiency because of blood loss. Heavy menstrual bleeding and gastrointestinal (GI) bleeding are potential causes.
Thalassemia: Thalassemia is an inherited disorder that disrupts your body’s ability to make hemoglobin. People with thalassemia may have a normal or increased number of red blood cells but low hemoglobin inside the cells (hypochromic microcytosis). Mild types of thalassemia cause microcytosis without anemia.
Anemia of chronic disease: Long-term conditions, including autoimmune diseases, infections, kidney disease and cancer, can cause inflammation that disrupts your body’s ability to use iron to make healthy red blood cells.
Less common causes of microcytosis include:

Rare inherited genetic conditions that interfere with the production and function of your red blood cells.
Mineral deficiencies (copper).
Lead poisoning.

Diagnosis and Tests

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Pub: 30 Mar 2024 08:16 UTC
Edit: 16 Jun 2024 08:37 UTC
Views: 365