Pernicious anemia

Causes and Risks:
People with pernicious anemia loose their ability to make intrinsic factor , a substance that enables vitamin B12 to be absorbed from the intestine. Vitamin B12 deficiency results.

This condition may result from hereditary factors. Congenital pernicious anemia is inherited as an autosomal recessive disorder.

Pernicious anemia is also seen in association with some autoimmune endocrine diseases such as type 1 diabetes , hypoparathyroidism , Addison's disease , hypopituitarism , testicular dysfunction, Graves disease , chronic thyroiditis , myasthenia gravis , secondary amenorrhea , vitiligo , and candidiasis . Gradually the deficiency of vitamin B12 affects sensory and motor nerves, causing neurological effects. The anemia also affects the gastrointestinal system and the cardiovascular system.

The disease can affect all racial groups, but the incidence is higher among people of Scandinavian or Northern European descent. Pernicious anemia usually does not appear before the age of 30, although a juvenile form of the disease can occur in children. Juvenile or congenital pernicious anemia is evident before the child is 3 years old.

Risk factors are a history of autoimmune endocrine disorders, a family history of pernicious anemia, and Scandinavian or Northern European descent. The incidence is 1 out of 1,000 people.

(See also megaloblastic anemia )

In the infant or young child, pernicious anemia may be secondary to poor absorption of vitamin B12 caused by some of the following conditions:
  • defect in absorption
  • celiac disease (sprue)
  • methylmalonic aciduria
  • homocystinuria
  • tuberculosis treatment with para amino salicylic acid
  • poor diet in the infant
  • maternal dietary deficiency while pregnant can cause pernicious anemia in an infant less than 4 months old



Prevention:
This condition is not preventable. Treatment will prevent continued symptoms.

Symptoms:

Additional symptoms that may be associated with this disease:



Signs and Tests:
Neurological signs or symptoms will develop if the disease goes untreated.

Tests that may indicate pernicious anemia include:

This disease may also alter the results of the following tests:



Treatment:
Vitamin B12 injections are the definitive treatment for this disorder. When treatment is initiated, 5 to 7 injections may be given in a short span of time. Response to this therapy is usually seen within 48 to 72 hours, so there is usually no need for blood transfusions as a treatment for very low blood counts. Life-long therapy (with vitamin B12 injections every month or two) is needed for this disorder. Oral (by mouth) vitamin B12 is not recommended because it will not produce the desired response (the problem is an inability to ABSORB vitamin B12, not a lack of the vitamin in the diet). A well-balanced diet is essential to provide other components for healthy blood cell development such as folic acid , iron, and vitamin C .

Prognosis:
The outcome is usually excellent with treatment.

Complications:



Call Your Healthcare Provider:
Call for an appointment with your health care provider if symptoms of pernicious anemia develop.


This picture shows large, dense, oversized, red blood cells (RBCs) that are seen in megaloblastic anemia. Megaloblastic anemia can occur when there is a deficiency of vitamin B-12.



Glossitis: Glossitis is an inflammatory condition of the tongue which results in reddening, loss of papilla (giving the tongue a smooth glossy appearance), and irritation. Glossitis may be associated with underlying disease.



Glossitis, medium rhomboid: Glossitis is an inflammatory condition of the tongue which results in reddening, loss of papilla (giving the tongue a smooth glossy appearance), and irritation. Glossitis may be associated with underlying disease. In this photograph, only a small area of the tongue is affected.