How Is Anemia Diagnosed?
Your doctor will diagnose anemia based on your  medical and family histories,  a physical exam, and results from tests  and procedures. 

Because  anemia doesn’t always cause symptoms, your doctor may find out  you have it while checking  for another condition. 

Medical and Family Histories

Your doctor may ask whether you have any of the  common signs or symptoms of anemia. He or she may ask whether  you’ve had an illness or condition that could cause anemia.

Your doctor also may ask about the medicines you take,  your diet, and whether you have family members who have anemia or a history of it.

Physical Exam

Your doctor will do a physical exam to find out  how severe your anemia is and to check for possible causes. He or she may: 

• Listen  to your heart for a rapid or irregular heartbeat 
• Listen  to your lungs for rapid or uneven breathing
• Feel your abdomen to check the size of your liver and spleen 

Your  doctor also may do a pelvic or rectal exam to check for common sources of blood loss.

Diagnostic Tests and Procedures

Your doctor may order various tests or procedures to find out what  type of anemia you have and how severe it is.
Complete Blood Count 

Often,  the first test used to diagnose anemia is a complete blood count (CBC). The CBC measures many different parts  of your blood. 

This test checks your  hemoglobin and hematocrit (hee-MAT-oh-crit) levels.  Hemoglobin is the iron-rich protein in red blood cells that carries oxygen to the body. Hematocrit  is a measure of  how much space red blood cells take up in your blood.  A low level of hemoglobin or  hematocrit is a sign of anemia.

The normal range of these levels may be lower in certain racial and ethnic populations. Your doctor can explain your test results to you. 

The CBC also checks the  number of red blood cells,  white blood cells, and  platelets in your blood. Abnormal results may be a sign of anemia, a blood disorder, an infection, or another condition. 

Finally, the CBC looks at  mean corpuscular (kor-PUS-kyu-lar)  volume (MCV). MCV is a measure of  the average size of your red blood cells and a clue as to the cause of your anemia.  In iron-deficiency  anemia, for example, red blood cells  usually are smaller than normal.

Other Tests and Procedures 

If the CBC results show that you have anemia, you  may need other tests such as: 

• Hemoglobin electrophoresis (e-lek-tro-FOR-e-sis). This test looks at  the different types of hemoglobin in your blood. It can help  diagnose the type  of anemia you have. 
• A reticulocyte  (re-TIK-u-lo-site) count. This test measures the number of young red blood cells  in your blood. The test shows  whether your bone marrow is making red blood cells  at the correct rate.
• Tests for  the level of iron in your blood and body. These include serum iron and  serum ferritin tests. Transferrin level and  total iron-binding capacity also test iron levels. 

Because anemia has many causes, you also may be tested for conditions such as kidney failure, lead poisoning (in children), and vitamin deficiencies (lack of vitamins, such as B12 and folic acid). 

If your doctor thinks that you have anemia due to internal bleeding, he  or she may suggest  several tests to look for  the source of the bleeding. A test to check the stool for blood may be done in your doctor’s office or at home.  Your doctor can give you a kit to help you get a sample at home. He or she  will tell you to bring the sample back to the  office or send it to a lab.

If blood is found in the stool, other tests may be used to find the source of the bleeding. One such test is endoscopy (en-DOS-ko-pe). For  this test, a tube with a tiny camera is used to view the lining of the digestive tract.

Your  doctor also may want to do bone marrow tests. These tests show  whether your bone marrow is healthy and making enough blood cells.