Definition, Symptoms, Causes & Treatment

What are pernicious anemia symptoms?

Generally speaking, the longer you go without adequate vitamin B12, the more serious your symptoms are. Early on, people may have mild symptoms they may think are caused by other common conditions. Examples include:

• Diarrhea or constipation.
• Lightheadedness when standing up or with exertion.
• Loss of appetite.
• Pale skin (mild jaundice or yellowing of your eyes or skin).
• Shortness of breath (dyspnea), mostly during exercise.
• Heartburn.
• Swollen, red tongue or bleeding gums.

What are examples of pernicious anemia symptoms caused by long-term low vitamin B12 levels?

Long-term low vitamin B12 levels caused by pernicious anemia can affect your nervous system. Symptoms of potential nervous system problems include:

• Confusion.
• Short-term memory loss.
• Depression.
• Loss of balance.
• Numbness and tingling in your hands and feet.
• Problems concentrating.
• Irritability.
• Hallucinations.
• Delusions.
• Optic nerve degeneration that affects your eyesight.

Can I have pernicious anemia without having symptoms?

Yes. Normally, your body stores vitamin B12 that it gets from what you eat. Your body stores vitamin B 12, slowly using it over time. It can take three to five years for your body to use up your vitamin B12 reserves. After that, it can be several more years before you develop pernicious anemia symptoms.

What causes pernicious anemia?

Pernicious anemia is an autoimmune condition that happens when your immune system produces antibodies that attack cells in the mucosal lining of your stomach and nerve cells. Your immune system’s response affects your body’s ability to absorb vitamin B12.

The antibodies also block a critical protein called intrinsic (in-TRIN-sic) factor. Normally, intrinsic factor carries the vitamin B12 we get from food to special cells in your small intestine. From there, the vitamin B12 is transported into your bloodstream. Other proteins then carry the vitamin B12 to your bone marrow, where the vitamin is used to make new red blood cells. This process can’t happen when your immune system blocks your intrinsic factor.

You may also develop vitamin B12 deficiency if:

• You have surgery to remove part or all of your stomach, which eliminates the cells that enable vitamin B12 absorption. About half of people who have gastric bypass surgery to treat obesity lose cells that enable vitamin B12 absorption.
• Part or all of your small intestine is surgically removed, reducing your small intestine’s ability to absorb vitamin B12.
• You have Small Intestine Bacterial Overgrowth (SIBO). SIBO happens when you have too many of the wrong kind of bacteria in your small intestine. This bacteria often uses up any vitamin B12 before your small intestine can absorb the vitamin.
• You take some medications, including antibiotics for infections and medicines for diabetes and seizures, which affect vitamin B12 levels.
• You have a tapeworm infection. You can get a tapeworm infection by eating infected fish that was undercooked. Tapeworms feed on vitamin B12.
• You follow a vegan or vegetarian diet that doesn’t include enough vitamin B12.
• You have medical conditions that affect your digestive system like celiac disease or Crohn’s disease that make it hard for your body to absorb enough vitamin B12.
• You have endocrine autoimmune diseases, such as hypoparathyroidism and Graves’ disease, that increase your risk for developing pernicious anemia.