Contents:
- Medical Video: What is Pernicious Anaemia?
- Lack of intrinsic factors
- Other causes
- Malabsorption in the small intestine
- Low vitamin B12 diet
Medical Video: What is Pernicious Anaemia?
Pernicious anemia is caused by a lack of intrinsic factors or other causes, such as infection, surgery, medication, or diet.
Lack of intrinsic factors
Intrinsic factor is a protein made in the stomach. This protein helps your body absorb vitamin B12. In some people, an autoimmune response causes intrinsic factors to decrease.
An autoimmune response occurs when the body's immune system makes antibodies (proteins) that attack and damage body tissues or cells.
In pernicious anemia, the body makes antibodies to attack and destroy parietal cells. These cells coat the stomach and make intrinsic factors. The cause of this autoimmune response is still unknown.
As a result of antibody attacks, the stomach stops producing intrinsic factors. Without intrinsic factors, the body is not able to deliver vitamin B12 through the small intestine as a place to absorb vitamins. This condition triggers vitamin B12 deficiency.
Lack of intrinsic factors can also occur if you have had abdominal surgery. This type of surgery reduces the number of parietal cells responsible for making intrinsic factors.
In rare cases, children are born with inherited disorders that prevent the body from making intrinsic factors. This disorder is called congenital pernicious anemia.
Other causes
Besides the lack of intrinsic factors, pernicious anemia is also caused by other factors. Malabsorption in the small intestine and low food intake of vitamin B12 can also cause pernicious anemia.
Malabsorption in the small intestine
Sometimes, pernicious anemia is caused by a disruption in the absorption of vitamin B12 in the small intestine. This disorder is triggered by:
- Too many bad bacteria in the small intestine. This condition is a common cause of pernicious anemia in adults. Bacteria use vitamin B12 before the small intestine finishes absorbing it.
- Diseases that interfere with the absorption of vitamin B12, such as celiac disease. Celiac disease is a genetic disorder when the body cannot receive a protein called gluten. Besides celiac, HIV disease and Crohn's disease (inflammatory bowel disease) can also interfere with the absorption of vitamin B12.
- Certain drugs that affect bacterial growth or inhibit the absorption of vitamin B12 by the small intestine. These drugs include antibiotics, seizure medications, and certain diabetes medications.
- Surgical removal of part or all parts of the small intestine.
- Tapeworm infection. Tapeworms take vitamin B12 intake in the body. The trigger for this infection is the consumption of tapeworm-infected fish, as well as eating habits of undercooked fish.
Low vitamin B12 diet
Some people suffer from pernicious anemia because they do not have enough vitamin B12 intake in their diet. The cause of pernicious anemia is less common than other causes.
Food sources rich in vitamin B12, including:
- Breakfast cereals containing vitamin B12
- Meat like beef, liver, poultry, and fish
- Eggs and dairy products (such as pure milk, yogurt and cheese)
- Foods fortified with vitamin B12, such as soy-based drinks and vegetarian burgers
Vegetarians who do not consume animals, milk products, and vitamin B12 supplements tend to be at risk of pernicious anemia.
Babies fed by vegetarian mothers are also at risk of developing pernicious anemia. These babies can show symptoms of anemia within a few months after birth. Because they don't have enough time to store vitamin B12 in their bodies. Generally, doctors will treat babies by providing vitamin B12 supplements.
Other groups, such as the elderly and alcoholics, may also be at risk for pernicious anemia. They may not get the right nutrition in their food.
