Definition

Anemia is a low level of healthy red blood cells (RBC). RBCs carry oxygen from the lungs to the rest of the body. When red blood cells are low the body does not get enough oxygen. This can cause symptoms such as fatigue, pale skin, or irregular heartbeat.

Pernicious anemia is associated with problems absorbing vitamin B12. This vitamin is needed to make healthy RBCs. Over time the low vitamin B12 levels will reduce the number of new RBCs. The sooner pernicious anemia is treated, the better the outcome.

Red Blood Cells

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Causes

There are many possible causes of pernicious anemia. These include:

    
  • Inflammation of the stomach—atrophic gastritis
  • Immune system reaction to:     
  • Intrinsic factor—a protein necessary for vitamin B12 absorption
  • Cells that produce both intrinsic factor and hydrochloric acid in the stomach
  • Removal of all or part of the stomach
  • Genetic defect
  • Risk Factors

    Pernicious anemia is more common in people over 50 years old, and in those of northern European or Scandinavian descent. Factors that may increase your chance of pernicious anemia include:

    Autoimmune disorders, such as:

        
  • Type 1 diabetes
  • Addison’s disease
  • Graves’ disease
  • Myasthenia gravis
  • Secondary amenorrhea
  • Hypoparathyroidism
  • Hypopituitarism
  • Testicular dysfunction
  • Chronic thyroiditis
  • Vitiligo
  • Idiopathic adrenocortical insufficiency
  • Symptoms

    Pernicious anemia symptoms can vary from person-to-person. They may change or worsen over time.

    Pernicious anemia may cause:

        
  • Sensation of pins and needles in feet or hands
  • Alternating constipation and diarrhea
  • Stinging sensation on the tongue, or a smooth red tongue
  • Substantial weight loss
  • Inability to distinguish the colors yellow and blue
  • Fatigue
  • Paleness
  • Loss of hunger
  • Altered sense of taste
  • Confusion
  • Depression
  • Impaired sense of balance, especially in the dark
  • Ringing in the ears—tinnitus
  • Cracked lips
  • Fever
  • Inability to sense vibrations in feet or legs
  • Lightheadedness when changing to standing position
  • Rapid heart rate
  • Diagnosis

    Your doctor will ask about your symptoms and medical history. A physical exam will be done.

    Blood tests are used to evaluate specific components to determine if there is a deficiency in proteins, vitamins, or building blocks.

    Other tests may include:

        
  • Bone marrow biopsy
  • Gastric cell biopsy
  • Shilling test (rare)—to evaluate the amount of stored vitamin B12
  • Treatment

    Talk with your doctor about the best treatment plan for you. Treatment options include the following:

    Vitamin B12 Injections

    The treatment consists of injections of vitamin B12 into a muscle. These injections are necessary because the intestines cannot absorb enough vitamin B12 without an adequate supply of intrinsic factor from the stomach.

    Oral Vitamin B12 Supplement

    If you are elderly, your doctor may advise you to take oral B12 supplements alone or in addition to injections of vitamin B12.

    Intranasal Vitamin B12

    Your doctor may give you a supplement of vitamin B12 that is sprayed into the nose.

    Oral Iron Therapy

    This treatment is recommended when an iron deficiency exists. In this case, the doctor will tell you to take iron supplements before treating with vitamin B12.

    Prevention

    There are no current guidelines to prevent pernicious anemia.