NCLEX RN Review (2019): Pernicious Anemia (B12 Deficiency)

NCLEX RN Review (2019): Pernicious Anemia (B12 Deficiency)

Welcome to this video tutorial on Pernicious
Anemia. Pernicious Anemia is an auto immune disorder in
which the body does not produce enough healthy red blood cells due to its inability to absorb
vitamin B12. Pernicious Anemia is caused by a lack of intrinsic factor, or IF in the stomach, which causes B12 deficiency. Pernicious actually means deadly and is used
because it was once considered a deadly disease due to the lack of available treatment. However, even today failure to diagnose and
treat in time can result in severe neurologic complications, leading to death. The disease was first clearly described in
1849 by Thomas Addison, from which it acquired the common name of Addison’s anemia. It may also be referred to as vitamin B12
deficiency. Intrinsic factor is a protein produced by
the parietal cells of the gastric mucosa, or stomach lining, that is necessary for the
absorption of vitamin B12 later on in the small intestine. Vitamin B12 is not produced by the body and
must be obtained from the diet. B12 is naturally found in animal products,
including meat, poultry, fish, eggs and dairy products. Fortified cereals and nutritional supplements
are another source. With vitamin B12 is consumed it travels to
the stomach where it binds with intrinsic factor, or IF, and the two are then absorbed
in the last part of the small intestine. In most cases a Pernicious Anemia, the body’s
immune system attacks and destroys the cells that produce IF in the stomach. When these cells are destroyed the body can’t
make IF, and therefore can’t absorb vitamin B12. Sometimes other causes of vitamin B12 deficiency
such as poor diet is confused with Pernicious Anemia. However, Pernicious Anemia is strictly caused
by a lack of IF, whether that be due to an autoimmune disorder, gastrectomy, or gastric
bypass surgery, or a genetic defect in which a child is born not making intrinsic factor. Without enough B12, the body will produce
macrocytes, or abnormally large red blood cells, which may not be able to enter the
bloodstream from the bone marrow resulting in a decrease in oxygen carrying red blood
cells in the bloodstream. Pernicious Anemia is sometimes called Megaloblastic
anemia, because of the abnormally large size of RVCs produced. It is not preventable and occurs in about
1 in 1000 people, usually between the ages of 40 to 70 years. Patients with Pernicious Anemia often have
other autoimmune disorders, as well as a two to three times increase risk of gastric cancer. The signs and symptoms are Pernicious Anemia are usually subtle and vague and many are due to anemia itself. There is a triad of classic symptoms including:
weakness or fatigue, sore tongue or glossitis, skin tingling or paresthesia. However, these are not always seen in all
patients. Additional symptoms include, but are not limited to: slight jaundice, pale skin with
dark circles around the eyes, thinning and early greying
of the hair and brittle nails, headaches, low grade fever, depressive mood, a swollen
red smooth tongue, sores at the corner of the mouth, known as angular cheilitis, loss
of appetite and weight loss, PICA which is the desire to eat ice or other non-food things,
such as dirt or paper, tachycardia, chest pain and the evidence of congestive heart
failure, altered blood pressure, shortness of breath, and nerve damage which can be permanent if treatment is not started within six months of symptoms. Severe Pernicious Anemia can lead to neurological
symptoms including: an unsteady gait or clumsiness, stiffness and tightness in the muscles, numbness in arms and legs, dementia, psychotic depression or psychosis, progressive lesions of the spinal
cord and death in serious cases. Diagnosis of Pernicious Anemia involves several
tests: a CBC, or complete blood count, a blood smear, Vitamin B12 deficiency blood test,
intrinsic factor antibody blood test, evaluation of gastric secretions, a stomach biopsy to
look for cell damage and the schilling test. However, it is no longer widely used. Treatment for Pernicious Anemia involves administration of vitamin B12. Either cyanocobalamin or hydroxocobalamin,
which will stop anemia related symptoms and neurological deterioration. If neurological problems are not advanced,
complete remission of all symptoms will occur as long as B12 is supplemented. Standard treatment of B12 is usually by intramuscular
injection, but oral doses also appear to be effective. Other methods include sublingual and intranasal
treatment, and experimental transdermal patches. Patient follow up is required to make sure
they respond to therapy and that they continue to receive therapy for the rest of their lives. B12 therapy resolves the anemia however, it
does not cure the chronic inflammation of the stomach mucosa. Which can progress to gastric cancer. When caring for the patient with Pernicious
Anemia, the nurse should: remind patients that their family members are at a greater risk of developing the disease and should be monitored for anemia and mental or neurological
symptoms. Teach the patient about eating a diet rich
in vitamin B12. Instructs strict vegetarians, particularly
those who do not eat eggs, milk or meat, to take supplementary B12 for their lifetime,
especially during pregnancy and breastfeeding. Let’s take a look at a quick review of Pernicious
Anemia. The body requires vitamin B12 and the protein
called intrinsic factor or IF to make red blood cells. Pernicious Anemia is an autoimmune disorder
in which the body doesn’t produce enough healthy red blood cells, due to its lack of IF and
inability to absorb vitamin B12. The three symptoms seen most often include weakness
and fatigue, sore tongue and skin tingling. If not treated symptoms can become more severe
leading to death. Treatment involves lifelong administration
of B12, but a person that is well treated can live a healthy life. Thank you for watching this video tutorial
on Pernicious Anemia. Don’t forget to subscribe and like it on Facebook
and take your Vitamin B-12.


  1. Oh wow! I always thought that pernicious anemia was just a low intake of VitB12; and not that it is strictly a lack of IF. Didn't know that!

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  3. the best video ever explaining Pernicious Anemia ,I have just had test and waiting for results ,so glad i found this video

  4. Good video but I think the treatment options listed are slightly off. If pernicious anemia is lack of intrinsic factor then how would oral intake help? Oral intake would be for Vitam B12 deficiency anemia and not pernicious anemia. They are very similar and both involve vitamin B12 deficiency but tx should be slightly different.

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