Microcytic Anemia

Overview

What is microcytic anemia?

Microcytic anemia happens when your red blood cells are smaller than usual because they don’t have enough hemoglobin. Hemoglobin is a protein in your red blood cells. It helps red blood cells carry oxygen throughout your body. Healthcare providers may refer to microcytic anemia as a medical condition or as a sign of certain anemias and other blood disorders. Healthcare providers treat microcytic anemia by identifying and treating what's causing it.

What is the most significant problem associated with microcytic anemia?

The most significant problem with microcytic anemia is that its symptoms can be mild or develop over time. You may not notice changes in your body right away that are signs something isn’t right. Microcytic anemia is a sign of other anemias and medical conditions that, if left untreated, may cause serious medical problems. That’s why it’s important to keep track of your overall health and talk to your healthcare provider if you notice changes.

What medical conditions cause microcytic anemia?

The following medical conditions cause microcytic anemia:

  • Iron-deficiency anemia (IDA): This anemia is the most common cause of microcytic anemia.
  • Thalassemias: These are blood disorders that affect your body’s ability to make hemoglobin and red blood cells.
  • Sideroblastic anemia: Sideroblastic anemia (SA) is a rare blood disorder that affects your bone marrow’s ability to make normal red blood cells.
  • Anemia of chronic disease: This form of anemia may develop if you have long-term illnesses that cause inflammation.
  • Lead poisoning: Exposure to lead for a long time may cause microcytic anemia.

Symptoms and Causes

What are the symptoms of microcytic anemia?

Microcytic anemia symptoms may include:

What’s the most common cause of microcytic anemia?

Microcytic anemia happens when something affects your bone marrow’s ability to create normal red blood cells. In some cases, microcytic anemia happens when you don’t have enough iron in your system or your body can’t absorb iron. Researchers have identified at least a dozen genetic disorders that may affect red blood cell development. Everyone’s situation is a bit different. If you have microcytic anemia, ask your healthcare provider about your situation.

Diagnosis and Tests

How do healthcare providers diagnose microcytic anemia?

Providers use these blood tests to diagnose microcytic anemia:

  • Complete blood count (CBC): This test gives providers information about your hemoglobin levels and aspects of your blood.
  • Peripheral blood smear: Providers use this test to examine your blood cells. While some blood tests analyze your blood cells with a machine, providers do the analysis by looking at blood cells under a microscope.
  • Reticulocyte count: This test measures the number of immature red blood cells (reticulocytes) in your bone marrow. A reticulocyte count can tell your provider if your bone marrow produces enough healthy red blood cells.

Management and Treatment

How do healthcare providers treat microcytic anemia?

Providers treat microcytic anemia by treating the underlying cause. For example, if you have iron-deficiency anemia, your provider may prescribe iron supplements.

Prevention

How can I reduce my risk?

You may not be able to reduce your risk of developing microcytic anemia. Microcytic anemia happens when something affects your body’s ability to make healthy red blood cells, and you may not be able to prevent some of those things from happening.

For example, iron deficiency is the most common cause of microcytic anemia. Sometimes people can prevent iron deficiency anemia by following an iron-rich diet. Other times, people have microcytic anemia because they have medical conditions that affect their bodies’ ability to absorb iron or they inherited a disorder that prevented their bodies from developing healthy red blood cells.

Outlook / Prognosis

What can I expect if I have microcytic anemia?

Microcytic anemia is a sign of other anemia types and medical conditions. Healthcare providers treat microcytic anemia by treating the underlying condition. Your provider is your best resource for information about your prognosis.

Is microcytic anemia serious?

Microcytic anemia is a sign of several other anemias and other blood disorders. If blood tests show you have microcytic anemia, your healthcare provider will do more tests to diagnose that underlying condition. Once they diagnose the problem, your provider will be able to explain how the problem affects your health. If you’re concerned you may have serious illness, your provider is your best resource for information about your situation.

Living With

How do I take care of myself?

If you have microcytic anemia, you can take care of yourself by following your healthcare providers’ recommendations on treatment and follow-up care. Here are some suggestions for living with anemia that may be helpful:

  • Follow a healthy diet. Anemia often happens when you don’t get enough iron, vitamin B12 and vitamin B9. You can develop for other reasons that have nothing to do with diet. Talk to your healthcare provider before you make big changes in your diet, including taking vitamin supplements.
  • Anemia is exhausting. Try to get as much rest as you can.
  • Drink enough water to stay hydrated.
  • Do your best to avoid infections by washing your hands frequently.

A note from Cleveland Clinic

Microcytic anemia is a sign of several types of anemias and other medical conditions. You may have been diagnosed with microcytic anemia after a routine blood test or a blood test to find out why you have certain symptoms. A blood test showing you have microcytic anemia is the first step toward identifying and solving the medical issue that caused your test result. You likely have questions about what this test result means and what to expect. If you do, ask your provider for more information about your test result and next steps.

Last reviewed by a Cleveland Clinic medical professional on 05/16/2022.

References

  • Busaleh F, Alasmakh OA, Almohammedsaleh F. Microcytic Anemia Hiding Vitamin B12 Deficiency Anemia. (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8791038/?msclkid=028e76c0c28411ecacb41e66bf8fad02) Cureus. 2021;13(12):e20741. Accessed 5/16/2022.
  • Cappellini MD, Russo R, Andolfo I, Iolascon A. Inherited microcytic anemias. (https://pubmed.ncbi.nlm.nih.gov/33275715/) Hematology Am Soc. 2020 Dec 4;2020(1):465-470. Accessed 5/16/2022.
  • Chaudhry HS, Kasarla MR. Microcytic Hypochromic Anemia. [Updated 2021 Aug 26]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2022 Jan-. Accessed 5/16/2022.
  • National Heart, Lung and Blood Institute. What is Anemia? Accessed 5/16/2022.

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