What Is Anemia?

Anemia is a blood disorder marked by a decreased amount of red blood cells (RBCs). People with anemia have insufficient hemoglobin, a protein in red blood cells that carries oxygen through the body.

Anemia is the most common blood disorder in Americans, and it can have far-reaching symptoms or none at all. Some of the most common symptoms include fatigue, shortness of breath, and headaches.

There are multiple types of anemia with diverse potential causes. Anemia is usually related to a failure to generate enough normal red blood cells, increased destruction of red blood cells, or blood loss. Anemia testing is essential to diagnosing anemia and identifying its underlying cause.

The Role of Anemia Testing

Routine blood testing, such as during a medical check-up, may reveal anemia in patients who have mild cases with few or no symptoms.

In people who have symptoms, diagnostic anemia testing can determine whether red blood cells are diminished. In-depth analysis of the blood often helps with finding the type and cause of anemia.

Because anemia is a blood disorder, most tests use a blood sample. However, doctors may need to check for different potential causes, which can involve other types of testing.

Types of Anemia Tests

The complete blood count (CBC) is an essential part of anemia testing. This test measures different types of cells in the blood. It is often used as part of a routine check-up and in diagnosing health problems, and it can reveal the presence of anemia.

The CBC analyzes the amount of various blood cells as well as a protein called hemoglobin in the blood. Other tests, described in the following tables, may be prescribed depending on your CBC results, symptoms, and health history.

Additional tests can help identify the type and cause of anemia, but most patients do not need extensive testing. Your doctor is in the best position to address which tests are most relevant in your situation.

Because anemia is a blood disorder, various tests, such as those in the table below, can be used to do an in-depth analysis of different components of the blood. Tests like a blood smear, white blood cell differential, and reticulocyte count can often help assess anemia after an abnormal CBC. Other listed blood tests may be warranted in more specific circumstances:

In some types of anemia, red blood cells are destroyed faster than they can be replaced. The following tests may be used to measure an abnormal breakdown of red blood cells:

Anemia can occur because of unidentified blood loss. When this cause is suspected, tests such as those in the table below may look for signs of blood loss especially in the gastrointestinal system:

Anemia can also occur alongside lowered platelets, which are the blood cells that help form blood clots and stop bleeding. Several tests can help measure blood coagulation:

Iron is necessary to create red blood cells, and a decreased amount of iron is the most common cause of anemia. Multiple tests can be employed to detect iron deficiency:

Your body needs certain vitamins to create red blood cells. Tests for nutritional deficiency may be ordered if your doctor considers this to be a possible cause of anemia in your case:


Other medical conditions can trigger anemia. Tests may be used in order to check for underlying illnesses that negatively affect major organs and other bodily systems:

Some types of infections disrupt the body’s ability to maintain a healthy number of red blood cells. Your doctor may test for signs of one of these infections if this is believed to be a potential cause of your low red blood cell count:

Getting Tested for Anemia

Anemia testing usually takes place in a doctor’s office, laboratory, or hospital. Most tests for anemia involve a blood sample that is drawn from your arm using a needle or from a prick of the finger.

Anemia can be detected on routine blood work, or tests for anemia may be ordered after a person has symptoms consistent with anemia. People receiving treatment for anemia may have follow-up testing to monitor their response to treatment.

Anyone with symptoms of anemia or other concerns about this condition should talk with their doctor to determine which tests would be most appropriate in their case.

At-home anemia testing

At-home test kits are available that can analyze blood levels that are relevant to anemia:

  • Tests measuring hemoglobin, a protein found in red blood cells that may be deficient in anemia.
  • Tests measuring levels of the protein ferritin in the blood that may indicate iron deficiency.

These kits involve obtaining a drop of blood after pricking your fingertip.

At-home testing does not diagnose anemia and is not a substitute for either medical care or testing ordered by a doctor and conducted in a controlled laboratory.


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