Anemia

Diagnosis

Physicians generally consider anemia to be a sign of another condition. Diagnostic techniques depend heavily upon what is thought to be causing the anemia. For simple cases related to iron or vitamin deficiency, the diagnostic process may be very straightforward, starting with a few blood tests. When doctors suspect that anemia is related to a more serious condition, the diagnostic process may be more in-depth. Physicians at Mayo Clinic have extensive experience diagnosing all types of anemia.

Medical History and Physical Exam

As a first step to diagnosing the cause of anemia, a physician will conduct an in-depth interview with the patient. He or she collects details about when the condition first appeared and the symptoms experienced by the patient. After gathering a medical history, the physician conducts a physical examination.

Blood Tests

The physician will then order blood tests, which are examined in the laboratory by an experienced pathologist. A hematocrit test shows the percentage of blood volume consistng of red blood cells. Hemoglobin is a measurement of the amount of oxygen-carrying red cell pigment in the blood. The size and shape of the red blood cells are also important, as is the distinction between isolated anemia and anemia associated with abnormalities in other types of blood cells, such as white blood cells and platelets. More complex tests are often conducted to find out the type and cause of a patient's anemia. Mayo's hematopathology laboratory acts as a national reference laboratory, providing physicians across the country with information and test results.

Diagnosis of Anemia Related to Underlying Conditions

Physicians who suspect an underlying chronic disease may use stool sampling, urine analysis, endoscopy, colonoscopy, imaging studies, a bone marrow biopsy or genetic testing to diagnose the condition. The tests chosen depend on the suspected condition.

Stool sampling — If physicians suspect internal bleeding, they may have the patient provide a stool sample for testing. If results reveal blood in the stool, physicians may investigate causes for internal bleeding using other diagnostic methods.

Urine analysis — Urine analysis may reveal the presence or absence of substances related to anemic conditions. Abnormalities found during laboratory testing may provide important clues to the patient's anemia-related condition.

Endoscopy — This test enables specialists to examine the inside of the stomach and other parts of the upper digestive tract for ulcers, tumors, hiatal hernias or other potential sources of bleeding. To conduct this procedure, physicians give patients a mild sedative before passing a thin tube down the throat and through the stomach. A light on the inside of the tube allows the doctor to see any abnormal areas. If necessary, cell samples can be extracted for examination under a microscope (biopsy) by a pathologist.

Colonoscopy — This test enables physicians to look for tumors or other problems in the large intestine. To conduct a colonoscopy, the physician gives patients a mild sedative before passing a thin tube up through the rectum. A light on the inside of the tube allows the doctor to see any abnormal areas in the rectum or intestines. If necessary, cell samples can be taken for examination under a microscope by a pathologist.

Imaging Studies — The following imaging studies may be used to diagnose anemia:

• X-rays generate a two-dimensional view of the body to help physicians locate abnormalities.
• Ultrasound involves the use of high-frequency sound waves to form images of the body that identify certain abnormalities such as a tumor. A technician places a wand-like device (transducer) on the surface of the abdomen while monitoring the image on the screen.
• Computed tomography (CT) scans generate two-dimensional images of the body. New technology available at Mayo Clinic allows three-dimensional reconstruction of the CT images.
• Magnetic resonance imaging (MRI) technology uses magnetic fields and radio waves to identify small abnormalities in the soft tissue of the body in two- and three-dimensional views.

Bone marrow biopsy — If doctors suspect a bone marrow problem, a bone marrow biopsy may be necessary. An experienced specialist inserts a needle into a bone in the back of the pelvis to collect a sample of bone marrow for examination. A bone marrow biopsy is a relatively minor procedure that can be performed safely in an outpatient setting with either a local anesthetic (numbing medication) or light anesthesia to help eliminate pain and discomfort.

Genetic tests and counseling — If Mayo doctors suspect that anemia is related to a genetic condition, they may recommend consultation with a genetic counselor. These professionals frequently work with patients on complex scientific and emotional issues. When genetic testing is applicable, the genetic counselor discusses the benefits, risks and limits of conducting these tests.