Pernicious Anemia and Vitamin B12 Deficiency: Which Causes Which?

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People who’ve been diagnosed with pernicious anemia have a lot of questions…One is, “Is pernicious anemia a symptom of vitamin B12 deficiency, or is it the other way around?” In order to explain, it helps to understand a few things about how vitamin B12 deficiency and pernicious anemia occur.

Pernicious Anemia and Vitamin B12 Deficiency: Which Causes Which? B12 Patch

What is pernicious anemia?

Pernicious anemia is a lack of red blood cells due to an inability to digest vitamin B12 from the foods you eat.  People get pernicious anemia when they are unable to absorb vitamin B12 through the digestive system, resulting in vitamin B12 deficiency.

Other names for pernicious anemia are vitamin B12 deficiency anemia and megaloblastic anemia, meaning that hemoglobin count decreases due to deformed red blood cells.

What is vitamin B12?

Vitamin B12 (cobalamin) is one of the B complex vitamins. Vitamin B12 is essential for neurological health, in addition to red blood cell production, cognitive functioning, and energy production.

Sources of vitamin B12 include beef, chicken, fish, cheese, and eggs

What causes pernicious anemia?

There are two possible causes of vitamin B12 malabsorption:

  • Damage to the stomach lining (gastritis)
  • Autoimmune condition that attacks intrinsic factor, a digestive enzyme required in order to absorb vitamin B12

Any time there is damage to the stomach, vitamin B12 deficiency and pernicious anemia are likely to occur. Risk factors for this type of pernicious anemia include gastrointestinal disorders (Crohn’s disease, celiac disease, and fibromyalgia), bariatric surgery (gastric bypass), alcoholism, and frequent vomiting from migraines.

Risk factors for developing autoimmune pernicious anemia include immune response disorders such as fibromyalgia, chronic fatigue syndrome, and celiac disease.

(Also read: Anemia: Frequently Asked Questions, Answered)

Are there any other causes of vitamin B12 deficiency?

Yes- pernicious anemia is just one way to develop vitamin B12 deficiency.  There are other possible causes, including:

  • Vitamin B12 malabsorption from medications, such as metformin or protein pump inhibitors (PPIs)
  • Vegan diet
  • Removal of the ileum (ileostomy)

(Also read: Vitamin Deficiencies and the People who are affected by them)

    What are the symptoms of pernicious anemia-vitamin B12 deficiency?

    Symptoms range for each individual, depending on the severity and duration of vitamin B12 deficiency and pernicious anemia.

    Symptoms of vitamin B12 deficiency include:

    • Chronic fatigue
    • Depression
    • Confusion (brain fog)
    • Memory loss
    • Anxiety
    • Paranoia
    • Hallucinations
    • Dizziness, vertigo
    • Muscle spasms
    • Muscle pain
    • Painful numbness and tingling in the extremities (hands, feet, arms, legs)
    • Partial paralysis
    • Sore, burning red tongue
    • Altered sense of taste
    • Difficulty swallowing
    • Tinnitus (ear ringing)
    • Vision problems
    • Poor muscle coordination
    • Difficulty grasping objects without dropping them
    • Difficulty walking without stumbling
    • Difficulty balancing on one foot
    • Restless legs syndrome
    • Infertility
    • Frequent miscarriages
    • Poor bladder control

    Diagnosis and treatment

    To diagnose pernicious anemia, your doctor will run a few blood tests, including vitamin B12 blood count and intrinsic factor antibody. However, symptoms indicating vitamin B12 deficiency the most conclusive in reaching a diagnosis, as many vitamin B12 blood screenings are inaccurate.

    For treatment, doctors generally prescribe several rounds of vitamin B12 injections, to be given over a predetermined time period.

    Additionally, you may boost vitamin B12 levels quicker by taking extra doses of over-the-counter (OTC) vitamin B12 as a supplement to vitamin B12 shots.

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    Pernicious anemia: MedlinePlus Medical Encyclopedia

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