How Is Pernicious Anemia Diagnosed?
Your doctor will diagnose pernicious anemia based on
your medical and family histories, a physical exam, and the results from
tests.
Your doctor will want to find out whether the
condition is due to a lack of intrinsic factor or another cause. He or she also
will want to find out how severe the problem is, so it can be treated properly.
Specialists Involved
Primary care doctors, such as family doctors,
internists, and pediatricians (doctors who treat children), often diagnose and
treat pernicious anemia. Other kinds of doctors also may be involved,
including:
- A neurologist (nervous system specialist)
- A cardiologist (heart specialist)
- A hematologist (blood disease specialist)
- A gastroenterologist (digestive tract
specialist)
Medical and Family Histories
Your doctor may ask about your
signs and symptoms. He or she also may
ask:
- Whether you've had any stomach or intestinal
surgeries
- Whether you have any digestive disorders, such as
celiac disease or Crohn's disease
- About your diet and any medicines you take
- Whether you have a family history of
anemia
or pernicious anemia
- Whether you have a family history of autoimmune
disorders (such as Addison's disease, type 1 diabetes, or Graves' disease).
Research suggests a link may exist between these autoimmune disorders and
pernicious anemia that's caused by an autoimmune response.
Physical Exam
During the physical exam, your doctor may check for
pale or yellowish skin and an enlarged liver. He or she may listen to your
heart for a rapid heartbeat or
heart
murmur.
Your doctor also may check for signs of nerve
damage. He or she may want to see how well your muscles, eyes, senses, and
reflexes work. Your doctor may ask questions or do tests to check your mental
status, coordination, and ability to walk.
Diagnostic Tests and Procedures
Blood tests and procedures can help diagnose
pernicious anemia and find out what's causing it.
Complete Blood Count
Often, the first test used to diagnose many types of
anemia is a
complete
blood count (CBC). This test measures many different parts of your blood.
For this test, a small amount of blood is drawn from a vein (usually in your
arm) using a needle.
A CBC 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. MCV can be a clue as to what's causing your anemia. In
pernicious anemia, the red blood cells are larger than normal
(macrocystic).
Other Blood Tests
If the CBC results confirm that you have anemia, you
may need other blood tests to find out what type of anemia you have.
A reticulocyte (re-TIK-u-lo-site) count 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. People who have
pernicious anemia have low reticulocyte counts.
Serum folate, iron, and iron-binding capacity tests
also can help show whether you have pernicious anemia or another type of
anemia.
Your doctor may recommend other blood tests to
check:
- Your vitamin B12 blood level. A low vitamin B12
level indicates pernicious anemia.
- Your homocysteine and methylmalonic acid (MMA)
levels. High levels of these substances in your body are a sign of pernicious
anemia.
- For intrinsic factor antibodies and parietal cell
antibodies. These antibodies also are a sign of pernicious anemia.
Bone Marrow Tests
Bone
marrow tests can show whether your bone marrow is healthy and making enough
red blood cells. The two bone marrow tests are aspiration (as-pi-RA-shun) and
biopsy.
For aspiration, your doctor removes a small amount
of fluid bone marrow through a needle. For a biopsy, your doctor removes a
small amount of bone marrow tissue through a larger needle. The samples are
then examined under a microscope.
In pernicious anemia, the bone marrow cells that
turn into blood cells are larger than normal (macrocystic). |