Learn About Pernicious Anemia

What is the definition of Pernicious Anemia?

Anemia is a condition in which the body does not have enough healthy red blood cells. Red blood cells provide oxygen to body tissues. There are many types of anemia.

Pernicious anemia is a decrease in red blood cells that occurs when the intestines cannot properly absorb vitamin B12.

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What are the alternative names for Pernicious Anemia?

Macrocytic achylic anemia; Congenital pernicious anemia; Juvenile pernicious anemia; Vitamin B12 deficiency (malabsorption); Anemia - intrinsic factor; Anemia - IF; Anemia - atrophic gastritis; Biermer anemia; Addison anemia

What are the causes of Pernicious Anemia?

Pernicious anemia is a type of vitamin B12 anemia. The body needs vitamin B12 to make red blood cells. You get this vitamin from eating foods such as meat, poultry, shellfish, eggs, and dairy products.

A special protein, called intrinsic factor (IF), binds vitamin B12 so that it can be absorbed in the intestines. This protein is released by cells in the stomach. When the stomach does not make enough intrinsic factor, the intestine cannot properly absorb vitamin B12.

Common causes of pernicious anemia include:

  • Weakened stomach lining (atrophic gastritis)
  • An autoimmune condition in which the body's immune system attacks the actual intrinsic factor protein or the cells in the lining of your stomach that make it.

In rare cases, pernicious anemia is passed down through families. This is called congenital pernicious anemia. Babies with this type of anemia do not make enough intrinsic factor. Or they cannot properly absorb vitamin B12 in the small intestine.

In adults, symptoms of pernicious anemia are usually not seen until after age 30. The average age of diagnosis is age 60.

You are more likely to develop this disease if you:

  • Are Scandinavian or Northern European
  • Have a family history of the condition

Certain diseases can also raise your risk. They include:

  • Addison disease
  • Graves disease
  • Hypoparathyroidism
  • Hypothyroidism
  • Myasthenia gravis
  • Loss of normal function of ovaries before 40 years of age (primary ovarian failure)
  • Type 1 diabetes
  • Testicular dysfunction
  • Vitiligo
  • Sjögren syndrome
  • Hashimoto disease
  • Celiac disease

Pernicious anemia can also occur after gastric bypass surgery.

What are the symptoms of Pernicious Anemia?

Some people do not have symptoms. Symptoms may be mild.

They can include:

  • Diarrhea or constipation
  • Nausea
  • Vomiting
  • Fatigue, lack of energy, or lightheadedness when standing up or with exertion
  • Loss of appetite
  • Pale skin (mild jaundice)
  • Shortness of breath, mostly during exercise
  • Heartburn
  • Swollen, red tongue or bleeding gums

If you have a low vitamin B12 level for a long time, you can have nervous system damage. Symptoms can include:

  • Confusion
  • Short-term memory loss
  • Depression
  • Loss of balance
  • Numbness and tingling in the hands and feet
  • Problems concentrating
  • Irritability
  • Hallucinations
  • Delusions
  • Optic nerve atrophy
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What are the current treatments for Pernicious Anemia?

The goal of treatment is to increase your vitamin B12 level:

  • Treatment involves a shot of vitamin B12 once a month. People with severely low levels of B12 may need more shots in the beginning.
  • Some people may be adequately treated by taking large doses of vitamin B12 supplements by mouth.
  • A certain type of vitamin B12 may be given through the nose.
Who are the top Pernicious Anemia Local Doctors?
Highly rated in

Sapienza University Of Rome

Medical Surgical Department Of Clinical Sciences And Translational Medicine, Sant'andrea Hospital, School Of Medicine 
Rome, IT 

Edith Lahner is in Rome, Italy. Lahner is rated as an Elite expert by MediFind in the treatment of Pernicious Anemia. She is also highly rated in 17 other conditions, according to our data. Her top areas of expertise are Pernicious Anemia, Gastritis, Vitamin B12 Deficiency Anemia, and Helicobacter Pylori Infection.

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Graduate Institute Of Clinical Dentistry

National Taiwan University 

Julia Chang is in Taiwan. Chang is rated as an Elite expert by MediFind in the treatment of Pernicious Anemia. She is also highly rated in 19 other conditions, according to our data. Her top areas of expertise are Folate-Deficiency Anemia, Vitamin B12 Deficiency, Pernicious Anemia, and Vitamin B12 Deficiency Anemia.

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Highly rated in

School Of Dentistry

Graduate Institute Of Oral Biology, National Taiwan University 

Chun-pin Chiang is in Taiwan. Chiang is rated as an Elite expert by MediFind in the treatment of Pernicious Anemia. They are also highly rated in 27 other conditions, according to our data. Their top areas of expertise are Folate Deficiency, Folate-Deficiency Anemia, Vitamin B12 Deficiency Anemia, and Vitamin B12 Deficiency.

What is the outlook (prognosis) for Pernicious Anemia?

Most people often do well with treatment.

It is important to start treatment early. Nerve damage can be permanent if treatment does not start within 6 months of symptoms.

What are the possible complications of Pernicious Anemia?

People with pernicious anemia may have gastric polyps. They are also more likely to develop gastric cancer and gastric carcinoid tumors.

People with pernicious anemia are more likely to have fractures of the back, upper leg, and upper forearm.

Brain and nervous system problems may continue or be permanent if treatment is delayed.

A woman with a low B12 level may have a false positive Pap smear. This is because vitamin B12 deficiency affects the way certain cells (epithelial cells) in the cervix look.

When should I contact a medical professional for Pernicious Anemia?

Call your provider if you have symptoms of vitamin B12 deficiency.

How do I prevent Pernicious Anemia?

There is no known way to prevent this type of vitamin B12 anemia. However, early detection and treatment can help reduce complications.

Megaloblastic anemia - view of red blood cells
What are the latest Pernicious Anemia Clinical Trials?
Cobalamin Supply and Metabolism in Healthy Children From Birth to the Age of 12 Months and in Their Mothers (Cbl_Neo)
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The Epidemiology, Management, and the Associated Burden of Mental Health, Atopic and Autoimmune Conditions, and Common Infections in Alopecia Areata
What are the Latest Advances for Pernicious Anemia?
Gastric neuroendocrine neoplasms and precursor lesions: Case reports and literature review.
Six Autoimmune Disorders Are Associated With Increased Incidence of Gastric Cancer: A Systematic Review and Meta-Analysis of Half a Million Patients.
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Who are the sources who wrote this article ?

Published Date: February 06, 2020
Published By: Todd Gersten, MD, Hematology/Oncology, Florida Cancer Specialists & Research Institute, Wellington, FL. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.

What are the references for this article ?

Antony AC. Megaloblastic anemias. In: Hoffman R, Benz EJ, Silberstein LE, et al, eds. Hematology: Basic Principles and Practice. 7th ed. Philadelphia, PA: Elsevier; 2018:chap 39.

Anusha V. Pernicious anemia/megaloblastic anemia. In: Kellerman RD, Rakel DP, eds. Conn's Current Therapy 2020. Philadelphia, PA: Elsevier; 2020:446-448.

Elghetany MT, Schexneider KI, Banki K. Erythrocytic disorders. In: McPherson RA, Pincus MR, eds. Henry's Clinical Diagnosis and Management by Laboratory Methods. 23rd ed. St Louis, MO: Elsevier; 2017:chap 32.

Means RT. Approach to the anemias. In: Goldman L, Schafer AI, eds. Goldman-Cecil Medicine. 26th ed. Philadelphia, PA: Elsevier; 2020:chap 149.