There are several types of blood tests that can be used to diagnose anemia. A complete blood count (CBC) is most commonly used, but other types of tests can also be useful. Some tests may also help determine what’s causing anemia.
Anemia happens when the level of red blood cells in your body is too low. Red blood cells are needed to carry oxygen to all the cells in your body.
In most cases, anemia can be easily diagnosed with specific blood tests. These tests look at factors such as how many red blood cells you have and the health of your blood cells. This information is then used to confirm a diagnosis of anemia.
This article takes a closer look at the types of tests that can be used to diagnose anemia and what the results mean.
There are a few common blood tests that can be used to diagnose anemia. The exact tests a doctor or healthcare professional may order depend on your symptoms, medical history, and the results of other tests.
Let’s take a closer look at some of the most common blood tests that are used to diagnose anemia.
Complete blood count
A complete blood count (CBC) is usually the first test that’s ordered to diagnose anemia. It’s often used to help diagnose other conditions, too.
A CBC measures the following levels in your blood:
- red blood cells
- white blood cells
When it’s used for anemia, doctors pay particularly close attention to your red blood cell and hemoglobin levels.
Another value that’s usually shown on a CBC, which may help diagnose anemia, is mean corpuscular volume. If this value is low, it may indicate a microcytic anemia, such as iron deficiency, and if this value is high, it may indicate a macrocytic anemia (B12 deficiency).
Sometimes anemia is caused by an iron deficiency. If a doctor thinks this may be the case, they’ll order a blood test known as an iron panel or serum iron test. This test will measure the level of iron in your blood.
An iron panel typically includes several lab values, including:
- ferritin, a protein that stores iron
- serum iron
- transferrin saturation
- total iron binding capacity
These values may help determine whether the cause of anemia is iron deficiency or chronic inflammation.
A reticulocyte count measures the number of immature red blood cells in your blood. It can help a doctor determine whether your bone marrow is producing enough red blood cells. This test is important because it can help pinpoint the cause of anemia.
For instance, if your CBC results show you have a low red blood cell count, but your reticulocyte count shows you have a high immature red blood cell count, it could mean you’re losing blood somehow.
Conversely, if you have low levels of both mature and immature red blood cells, it may mean your body isn’t making enough red blood cells.
A blood smear is another test that can be used to help pinpoint the possible cause of anemia.
A blood smears is done by spreading a drop of blood on a medical slide. A staining liquid is then added to the slide, which can help find any abnormalities in the shape of the blood cells.
This test may be particularly helpful in diagnosing sickle cell anemia, which is characterized by crescent-shaped red blood cells. It may also be helpful for diagnosing some nutritional deficiencies, which can cause very large red blood cells.
- If a type of anemia called hemolytic anemia is suspected (red blood cells are destroyed faster than the bone marrow can make them), the following tests may be done:
- Lactate dehydrogenase (LDH) test: This test measures a type of enzyme known as LDH that’s found in almost all tissues in your body. If your LDH levels are high, it may mean certain tissues in your body have been damaged by disease (such as anemia) or injury.
- Haptoglobin test: A haptoglobin test can help detect what type of anemia you have and possibly also help determine the cause of increased red blood cell destruction.
- Indirect bilirubin: Indirect bilirubin is the difference between your total and direct bilirubin. This level can increase if your body destroys too many red blood cells.
- Vitamin B12 and folate levels: These are commonly checked to rule out vitamin deficiency as a cause.
- A Coombs test: This is often done if an autoimmune disease is suspected as the cause of anemia.
Different factors such as your age, race, and the altitude at which you live can affect what’s considered a healthy range for various anemia blood tests. Talk with a doctor about what’s considered a healthy range for you.
- CBC (red blood cells): Healthy results for a red blood count are
5 to 6 million cells per microliter (cells/mcL)for men and 4 to 5 million cells/mcLfor women. Values below these levels may indicate anemia.
- CBC (hemoglobin): Healthy results are above
14 grams per deciliter (gm/dL) for men and above 12 gm/dL for women.
- Iron: Healthy iron levels in the blood start at
10 micromoles per liter (µmol/L).
- Ferritin: Ferritin is measured in an iron panel. Healthy levels start at
40 micrograms per liter (µg/L) for men and 20 µg/L for women.Levels below 10 µg/L may be a sign of anemia.
- Reticulocyte: Normal results for reticulocytes in adults are between
0.5 and 2.5%.
- Blood smear: A blood smear looks at the shape of your blood cells. Abnormally shaped red blood cells can be a sign of sickle cell anemia.
If your blood test results don’t confirm an anemia diagnosis, a doctor will likely order additional tests to determine what’s causing your symptoms.
We use “women” and “men” in this article to reflect the terms that have been historically used to gender people. But your gender identity may not align with how your body responds to this disease. A doctor can help you better understand how your specific circumstances will translate into diagnosis, symptoms, and treatment.
In some cases, additional tests may be necessary. This typically happens when a doctor knows you have anemia but needs more information to determine what’s causing it. The types of tests that may be ordered include:
- Bone marrow biopsies and aspirations: Bone marrow aspirations and biopsies are done by inserting a long, thin, and hollow needle into a bone to extract bone marrow fluid and tissue. This allows doctors to see if the bone marrow is healthy and able to make enough healthy blood cells.
- Urinalysis: A urinalysis test looks for blood in your urine and checks your kidney function.
- Endoscopy: An endoscopy is done by inserting a thin tube with a tiny camera on the end into your mouth and through the upper digestive tract. This allows doctors to look for bleeding in your esophagus, stomach, and small intestine.
- Colonoscopy: A colonoscopy is done by inserting a thin tube with a small camera into the rectum to look for bleeding in the colon (large intestine).
- Genetic tests: A genetic test can look for changes to the genes that are programmed to make red blood cells.
Anemia symptoms sometimes develop slowly. In other cases, they can come on suddenly. The underlying cause of anemia is a factor in determining how quickly symptoms develop.
No matter how quickly or slowly they develop, when symptoms appear, they typically include:
- shortness of breath
- dizziness or lightheadedness
- pale skin and gums
If you experience any of these symptoms for more than a week, it’s a good idea to make an appointment with a doctor. They can help diagnose the cause of your symptoms and create the right type of treatment plan for you.
(Video) Complete Blood Count (CBC) Test Results Interpretation w/ Differential Nursing NCLEX
If you have symptoms such as ongoing fatigue, weakness, or dizziness, a doctor will likely order one or multiple types of blood tests to determine if you have anemia. A test called a CBC is often the first test that will be done to help diagnose anemia. This test measures the level of red blood cells in your blood and is a reliable indicator of anemia.
Other common blood tests include an iron panel, a reticulocyte test, and a blood smear. These tests can also help doctors determine the underlying cause of anemia and how to best treat this condition.
Hemoglobin. Lower than normal hemoglobin levels indicate anemia. The normal hemoglobin range is generally defined as 13.2 to 16.6 grams (g) of hemoglobin per deciliter (dL) of blood for men and 11.6 to 15 g/dL for women.What lab values are abnormal for anemia? ›
Anemia occurs when you do not have enough red blood cells or when your red blood cells do not function properly. It is diagnosed when a blood test shows a hemoglobin value of less than 13.5 gm/dl in a man or less than 12.0 gm/dl in a woman. Normal values for children vary with age.How do you read anemia lab results? ›
- For men: Hemoglobin < 14 g/dL (140 g/L), hematocrit < 42% (< 0.42), or RBC < 4.5 million/mcL (< 4.5 × 10 12/L)
- For women: Hemoglobin < 12 g/dL (120 g/l), hematocrit < 37% (< 0.37), or RBC < 4 million/mcL (< 4 × 10 12/L)
The anemia is also classified by severity into mild (110 g/L to normal), moderate (80 g/L to 110 g/L), and severe anemia (less than 80 g/L) in adults.What CBC results indicate iron-deficiency anemia? ›
- Low mean corpuscular volume (MCV)
- Low mean corpuscular hemoglobin concentration (MCHC)
- Elevated platelet count (>450,000/µL) in many cases.
- Normal or elevated white blood cell count.
Ferritin. Ferritin is the best indicator of iron deficiency and a low ferritin alone is diagnostic of IDA. Iron is stored intracellularly as ferritin and in the presence of infection, malignancy or chronic inflammation, the ferritin rises as it is an acute phase protein.What is bad anemia number? ›
Mild: Hemoglobin 10.0 g/dL to lower limit of normal. Moderate: Hemoglobin 8.0 to 10.0 g/dL. Severe: Hemoglobin 6.5 to 7.9 g/dL Life-threatening: Hemoglobin less than 6.5 g/dL.What is the normal range for blood test results? ›
Lab results are often shown as a set of numbers known as a reference range. A reference range may also be called "normal values." You may see something like this on your results: "normal: 77-99mg/dL" (milligrams per deciliter). Reference ranges are based on the normal test results of a large group of healthy people.What is the normal percentage for anemia? ›
In adults, normal levels for men range from 41%-50%. For women, the normal range is slightly lower: 36%-44%. A hematocrit level below the normal range, meaning the person has too few red blood cells, is called anemia.How do I know what type of anemia I have? ›
Hemoglobin electrophoresis (e-lek-tro-FOR-e-sis). This test looks at the different types of hemoglobin in your blood. The test can help diagnose the type of anemia you have.
Anemia can be classified as microcytic, normocytic or macrocytic, depending on MCV.What are the 3 types of anemia? ›
Many types of anemia exist, such as iron-deficiency anemia, pernicious anemia, aplastic anemia, and hemo- lytic anemia. The different types of anemia are linked to various diseases and conditions. Anemia can affect people of all ages, races, and ethnici- ties.Would anemia show up on a CBC? ›
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.What is the gold standard for diagnosing iron deficiency anemia? ›
The “gold standard” for identifying iron deficiency is bone marrow biopsy with Prussian blue staining. Since, bone marrow aspiration is an invasive procedure, indirect assays are used for routine use.What are the best indicators of iron status? ›
Hemoglobin and ferritin are currently the most efficient indicators of population response to iron interventions: an analysis of nine randomized controlled trials.What are the most important numbers in a blood test? ›
- The number and size of red blood cells (these cells carry oxygen)
- The number of white blood cells (these cells help fight infection)
- Total amount of hemoglobin and amount per red blood cell (this protein carries oxygen in red blood cells)
Borderline. Take no action – This means that the doctor has looked at the result and deemed it to be just outside of the normal range and the result is not concerning. Abnormal but expected.What is the standard range? ›
Usual or optimal
Reference ranges are usually given as what are the usual (or normal) values found in the population, more specifically the prediction interval that 95% of the population fall into. This may also be called standard range.
Mild anemia is a common and treatable condition that can develop in anyone. It may come about suddenly or over time, and may be caused by your diet, medicines you take, or another medical condition. Anemia can also be chronic, meaning it lasts a long time and may never go away completely.Can anemia turn into leukemia? ›
“Anemia cannot cause leukemia but could be a sign of bone marrow that's not producing enough red blood cells,” Dr. Wetmore explained. “This requires an investigation (lab tests) into the cause of low numbers of red blood cells.”
Anemia can affect your weight, often as a result of its impact on your appetite or activity levels. The underlying cause of a particular type of anemia may also lead to weight loss or gain.What type of anemia is most common? ›
Iron deficiency anemia is the most common type of anemia.What is the main cause of anemia? ›
The most common cause of anemia is not having enough iron. Your body needs iron to make hemoglobin. Hemoglobin is an iron-rich protein that gives the red color to blood. It carries oxygen from the lungs to the rest of the body.Can stress cause anemia? ›
Sustained stress is another cause of anaemia. Excessive stress hinders the manufacture of hydrochloric acid in your body, which is very important for the integration of iron and proteins. The deficiency of iron is equal to lack of haemoglobin and thus, anaemia.Is low B12 anemia? ›
Vitamin B12–deficiency anemia, also known as cobalamin deficiency, is a condition that develops when your body can't make enough healthy red blood cells because it doesn't have enough vitamin B12. Your body needs vitamin B12 to make healthy red blood cells, white blood cells, and platelets.What are the 4 stages of anemia? ›
- First stage: Iron stores are depleted. ...
- Second stage: When iron stores are low, the normal process of making red blood cells is altered. ...
- Third stage: Iron-deficiency anemia develops because there isn't enough iron to make hemoglobin for red blood cells.
Because symptoms such as difficulty sleeping, lack of energy, fatigue, racing heartbeat, and restlessness are so closely linked to depression and anxiety, they can sometimes be mistaken for these mental health concerns. Severe progressions of the illness can cause these symptoms.Does low hematocrit mean anemia? ›
A hematocrit level below the normal range, meaning the person has too few red blood cells, is called anemia. A hematocrit level above the normal range, meaning too many red blood cells, may indicate polycythemia or erythrocytosis.Does low RBC mean anemia? ›
A low RBC count, also known as anemia, can affect the body's ability to transport oxygen and nutrients around the cardiovascular system. It can cause fatigue, dizziness, and heart palpitations. The most common form of anemia is iron deficiency anemia. This can result from blood loss, malnutrition, or kidney problems.What is a mild anemia range? ›
Mild anemia corresponds to a level of hemoglobin concentration of 10.0-10.9 g/dl for pregnant women and children under age 5 and 10.0-11.9 g/dl for nonpregnant women. For all of the tested groups, moderate anemia corresponds to a level of 7.0-9.9 g/dl, while severe anemia corresponds to a level less than 7.0 g/dl.
A high red blood cell count is generally considered to be anything above 6.1 million red blood cells for males, 5.4 million for females, and 5.5 for children. Additional tests will help your healthcare provider determine the cause of your high red blood cell count and next steps in your care.What is normal CBC values? ›
|Hematocrit (%)||40 to 50||35 to 43|
|RBC count (×106/microL)||4.2 to 5.7||3.8 to 5.0|
|MCV (fL)||82.5 to 98|
|MCHC||32.5 to 35.2|
Anemia is a reduction in hemoglobin (Hb) or hematocrit (HCT) or RBC count. It is a presentation of an underlying condition and can be subdivided into macrocytic, microcytic, or normocytic. Patients with anemia typically present with vague symptoms such as lethargy, weakness, and tiredness.Is low HGB and HCT anemia? ›
When Levels Are Low. Usually, low hemoglobin or low hematocrit means that you are not producing enough red blood cells or that you are losing red blood cells due to acute bleeding, a bleeding disorder, or accelerated destruction of red blood cells.What is a dangerously low level of hematocrit? ›
A hematocrit level below 35% in women and 41% in men is low. A level under this value can signify chronic anemia .
An adult has anemia, or is considered anemic, when their hemoglobin level falls to about 100g/L or less. A child has anemia if the hemoglobin is 75 g/L or less.Is 3.7 RBC count too low? ›
A normal RBC count would be around: men – 4.0 to 5.9 x 10*12/L. women – 3.8 to 5.2 x 10*12/L.Does anemia make you cold? ›
Anemia occurs when there aren't enough healthy red blood cells to carry oxygen to your body's organs. As a result, it's common to feel cold and symptoms of tiredness or weakness.