Anisocytosis is a medical condition in which the red blood cells present different sizes, these being commonly uniform in size. This condition is often encountered in patients who are suffering from different types of anemia and it is diagnosed through blood testing. The name comes from “aniso”, which means that something is not equal and “cytosis”, which makes reference to the part of the body that presents the above-mentioned characteristic (cell).

Anisocytosis Symptoms

These are the most common symptoms of anisocytosis:

  • Fatigue
  • The patient feels tired all the time
  • The lack of energy affects the daily living activities and the professional performance
  • One gets tired quite easily, without having to make too much effort
  • Shortness of breath
  • Given the fact that the red blood cells present different sizes, this means that the oxygen transportation is more difficulty made, hence the shortness of breath
  • Increased heart rhythm
  • As the distribution of the oxygen is not that efficient, the heart pumps more blood to compensate for the problem, hence the rapid heartbeat
  • The increased heart rhythm is present without the patient making excessive physical effort
  • Pale skin
  • This is also a sign that the oxygen does not travel in an efficient manner to the tissues.


These are the most common causes of anisocytosis:

  • Iron deficiency
  • This is one of the most common types of anemia, in which the red blood cells are deficient in iron
  • The lack of iron for prolonged periods of time can affect the red blood cells, causing them to change their size and lead to the appearance of anisocytosis
  • Vitamin A deficiency
  • The lack of normal levels of vitamin A throughout the body can be responsible for the unequal sizes of the red blood cells
  • Vitamin B12 deficiency (folate deficiency)
  • This is commonly known as pernicious anemia
  • The reduced levels of vitamin B12 in the body can lead to irregular sizes of red blood cells and to the appearance of nervous disorders, besides the anisocytosis
  • Diamond-Blackfan anemia
  • The bone marrow lacks the necessary capacity of producing sufficient quantities of red blood cells
  • The unequal size of the red blood cells appears as one of the signs of this particular type of anemia
  • Myelodysplastic syndrome
  • The bone marrow does not function as it should, presenting a set of abnormalities
  • The red blood cells present different sizes, leading to the appearance of anisocytosis symptoms
  • Blood transfusion
  • This occurs when the cells of the recently transfused blood differ in size from the ones inside the body
  • Unlike the other medical conditions presented above, the anisocytosis encountered in blood transfusions in only temporary
  • Other conditions
  • Sickle cell anemia
  • Autoimmune hemolytic anemia
  • Thalassemia
  • Dimorphic anemia
  • Chronic liver disease.


These are the most common methods used for the diagnosis of anisocytosis:

  • Microscopic analysis of the red blood cells
  • Blood smear – reveals the different sizes of the red blood cells
  • Red blood cell distribution width (RDW) – this is useful in determining how varied the size of the red blood cells actually is, confirming thus the diagnosis of anisocytosis

It is important to perform a thorough and detailed assessment of the patient, his/her medical history and blood tests. This is because there are other conditions that can mimic the changes encountered in anisocytosis, as it happens with patients who have an increased count of the white blood cells or abnormally large blood platelets.


As a condition per say, anisocytosis cannot be cured. However, the treatment has to address the condition that has led to its appearance in the first place. Vitamin and iron supplements are commonly used for the patients who are suffering from different types of anemia.For those who are suffering from iron-deficiency anemia, the treatment solutions might include:

  • Iron supplements
  • Change in the diet so as to include more foods that are rich in iron (peas, lentils, dried fruits, spinach, dark green leafy veggies and prune juice)
  • Vitamin C supplements – help with the absorption of the iron
  • Blood transfusions – for severe cases
  • IV iron therapy – last alternative for severe cases and in patients who cannot take oral iron supplements

In case of vitamin A deficiency, these are the recommended treatment measures to be taken:

  • Vitamin A supplements
  • Eating foods that are rich in vitamin A (liver, chicken, beef, eggs, carrots, mango, potatoes, leafy green veggies)

The vitamin B12 deficiency can be treated with:

  • Vitamin B12 supplements
  • Eating foods that are rich in vitamin B12 (meat, poultry, fresh seafood, dairy, eggs)

The treatment for Diamond-Blackfan anemia consists of:

  • Corticosteroids
  • Red blood cell transfusion
  • Bone marrow transplant

The following treatment approaches are used for the myelodysplastic syndrome:

  • Supportive therapy
  • Blood cell transfusion
  • Treatment of infections
  • Bone marrow transplantation
  • Cytotoxic chemotherapy

Sickle cell anemia can be treated through the following measures:

  • Non-steroidal anti-inflammatory drugs
  • Hydroxyurea
  • Blood cell transfusion
  • Antibiotics for the treatment of infections

Autoimmune hemolytic anemia is treated with:

  • Blood cell transfusion
  • Corticosteroids
  • Hydroxyurea
  • Plasmapheresis
  • Surgical removal of the spleen

Thalassemia is treated through the following medical solutions:

  • Blood cell transfusion
  • Iron chelators – remove the excess iron in the body, accumulated through the regular blood transfusions

Dimorphic anemia can be treated through these measures:

  • Vitamin B12 and iron supplements – these patients experience deficiencies of both vitamin B12 and iron
  • Eating foods that are rich in vitamin B12 and iron
  • Intravenous iron therapy
  • Vitamin C supplements to increase the absorption of iron in the body
  • Blood transfusions

For patients suffering from chronic liver disease, the treatment measures include:

  • Symptomatic medication – morphine in more severe cases
  • Supportive care
  • Blood transfusions
  • Liver transplant from compatible donor.

In conclusion, in order to successfully eliminate the symptoms caused by anisocytosis, one must first treat the underlying condition. As you have seen, some of these conditions are chronic and there is no treatment at the moment for them. However, the quality of life can be greatly improved by the regular administration of red blood cell transfusions.

May 27, 2015
Diseases and Conditions

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