Question: What causes Pernicious Anemia ?
Answer: Pernicious anemia is caused by a lack of intrinsic factor or other causes, such as infections, surgery, medicines, or diet. Lack of Intrinsic Factor Intrinsic factor is a protein made in the stomach. It helps your body absorb vitamin B12. In some people, an autoimmune response causes a lack of intrinsic factor. An autoimmune response occurs if the bodys immune system makes antibodies (proteins) that mistakenly attack and damage the body's tissues or cells. In pernicious anemia, the body makes antibodies that attack and destroy the parietal (pa-RI-eh-tal) cells. These cells line the stomach and make intrinsic factor. Why this autoimmune response occurs isn't known. As a result of this attack, the stomach stops making intrinsic factor. Without intrinsic factor, your body can't move vitamin B12 through the small intestine, where it's absorbed. This leads to vitamin B12 deficiency. A lack of intrinsic factor also can occur if you've had part or all of your stomach surgically removed. This type of surgery reduces the number of parietal cells available to make intrinsic factor. Rarely, children are born with an inherited disorder that prevents their bodies from making intrinsic factor. This disorder is called congenital pernicious anemia. Other Causes Pernicious anemia also has other causes, besides a lack of intrinsic factor. Malabsorption in the small intestine and a diet lacking vitamin B12 both can lead to pernicious anemia. Malabsorption in the Small Intestine Sometimes pernicious anemia occurs because the body's small intestine can't properly absorb vitamin B12. This may be the result of: Too many of the wrong kind of bacteria in the small intestine. This is a common cause of pernicious anemia in older adults. The bacteria use up the available vitamin B12 before the small intestine can absorb it. Diseases that interfere with vitamin B12 absorption. One example is celiac disease. This is a genetic disorder in which your body can't tolerate a protein called gluten. Another example is Crohn's disease, an inflammatory bowel disease. HIV also may interfere with vitamin B12 absorption. Certain medicines that alter bacterial growth or prevent the small intestine from properly absorbing vitamin B12. Examples include antibiotics and certain diabetes and seizure medicines. Surgical removal of part or all of the small intestine. A tapeworm infection. The tapeworm feeds off of the vitamin B12. Eating undercooked, infected fish may cause this type of infection. Diet Lacking Vitamin B12 Some people get pernicious anemia because they don't have enough vitamin B12 in their diets. This cause of pernicious anemia is less common than other causes. Good food sources of vitamin B12 include: Breakfast cereals with added vitamin B12 Meats such as beef, liver, poultry, and fish Eggs and dairy products (such as milk, yogurt, and cheese) Foods fortified with vitamin B12, such as soy-based beverages and vegetarian burgers Strict vegetarians who don't eat any animal or dairy products and don't take a vitamin B12 supplement are at risk for pernicious anemia. Breastfed infants of strict vegetarian mothers also are at risk for pernicious anemia. These infants can develop anemia within months of being born. This is because they haven't had enough time to store vitamin B12 in their bodies. Doctors treat these infants with vitamin B12 supplements. Other groups, such as the elderly and people who suffer from alcoholism, also may be at risk for pernicious anemia. These people may not get the proper nutrients in their diets.
Source: NHLBI

Question: Who is at risk for Pernicious Anemia? ?
Answer: Pernicious anemia is more common in people of Northern European and African descent than in other ethnic groups. Older people also are at higher risk for the condition. This is mainly due to a lack of stomach acid and intrinsic factor, which prevents the small intestine from absorbing vitamin B12. As people grow older, they tend to make less stomach acid. Pernicious anemia also can occur in younger people and other populations. You're at higher risk for pernicious anemia if you: Have a family history of the condition. Have had part or all of your stomach surgically removed. The stomach makes intrinsic factor. This protein helps your body absorb vitamin B12. Have an autoimmune disorder that involves the endocrine glands, such as Addison's disease, type 1 diabetes, Graves' disease, or vitiligo. Research suggests a link may exist between these autoimmune disorders and pernicious anemia that's caused by an autoimmune response. Have had part or all of your small intestine surgically removed. The small intestine is where vitamin B12 is absorbed. Have certain intestinal diseases or other disorders that may prevent your body from properly absorbing vitamin B12. Examples include Crohn's disease, intestinal infections, and HIV. Take medicines that prevent your body from properly absorbing vitamin B12. Examples of such medicines include antibiotics and certain seizure medicines. Are a strict vegetarian who doesn't eat any animal or dairy products and doesn't take a vitamin B12 supplement, or if you eat poorly overall.
Source: NHLBI

Question: How to diagnose Pernicious Anemia ?
Answer: Your doctor will diagnose pernicious anemia based on your medical and family histories, a physical exam, and test results. 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 the severity of the condition, so it can be properly treated. Specialists Involved Primary care doctorssuch 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, Graves' disease, or vitiligo). 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 rapid or irregular heartbeats or a 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 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 (HEE-muh-glow-bin) and hematocrit (hee-MAT-oh-crit) levels. Hemoglobin is an iron-rich protein that helps red blood cells carry oxygen from the lungs to the rest of 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 (PLATE-lets) in your blood. Abnormal results may be a sign of anemia, another 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 tend to be larger than normal. 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. Another common test, called the Combined Binding Luminescence Test, sometimes gives false results. Scientists are working to develop a more reliable test. Your doctor may recommend other blood tests to check: Your vitamin B12 level. A low level of vitamin B12 in the blood indicates pernicious anemia. However, a falsely normal or high value of vitamin B12 in the blood may occur if antibodies interfere with the test. 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.
Source: NHLBI

Question: What are the treatments for Pernicious Anemia ?
Answer: Doctors treat pernicious anemia by replacing the missing vitamin B12 in the body. People who have pernicious anemia may need lifelong treatment. The goals of treating pernicious anemia include: Preventing or treating the anemia and its signs and symptoms Preventing or managing complications, such as heart and nerve damage Treating the cause of the pernicious anemia (if a cause can be found) Specific Types of Treatment Pernicious anemia usually is easy to treat with vitamin B12 shots or pills. If you have severe pernicious anemia, your doctor may recommend shots first. Shots usually are given in a muscle every day or every week until the level of vitamin B12 in your blood increases. After your vitamin B12 blood level returns to normal, you may get a shot only once a month. For less severe pernicious anemia, your doctor may recommend large doses of vitamin B12 pills. A vitamin B12 nose gel and spray also are available. These products may be useful for people who have trouble swallowing pills, such as older people who have had strokes. Your signs and symptoms may begin to improve within a few days after you start treatment. Your doctor may advise you to limit your physical activity until your condition improves. If your pernicious anemia is caused by something other than a lack of intrinsic factor, you may get treatment for the cause (if a cause can be found). For example, your doctor may prescribe medicines to treat a condition that prevents your body from absorbing vitamin B12. If medicines are the cause of your pernicious anemia, your doctor may change the type or dose of medicine you take. Infants of strict vegetarian mothers may be given vitamin B12 supplements from birth.
Source: NHLBI

Question: How to prevent Pernicious Anemia ?
Answer: You can't prevent pernicious anemia caused by a lack of intrinsic factor. Without intrinsic factor, you won't be able to absorb vitamin B12 and will develop pernicious anemia. Although uncommon, some people develop pernicious anemia because they don't get enough vitamin B12 in their diets. You can take steps to prevent pernicious anemia caused by dietary factors. Eating foods high in vitamin B12 can help prevent low vitamin B12 levels. Good food sources of vitamin B12 include: Breakfast cereals with added vitamin B12 Meats such as beef, liver, poultry, and fish Eggs and dairy products (such as milk, yogurt, and cheese) Foods fortified with vitamin B12, such as soy-based beverages and vegetarian burgers If youre a strict vegetarian, talk with your doctor about having your vitamin B12 level checked regularly. Vitamin B12 also is found in multivitamins and B-complex vitamin supplements. Doctors may recommend supplements for people at risk for vitamin B12 deficiency, such as strict vegetarians or people who have had stomach surgery. Older adults may have trouble absorbing vitamin B12. Thus, doctors may recommend that older adults eat foods fortified with vitamin B12 or take vitamin B12 supplements.
Source: NHLBI