pernicious anemia

pernicious anemia: see anemia.

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pernicious anemia

Slow-developing disease in which vitamin B₁₂ (see vitamin B complex) deficiency impairs red-blood-cell production. It can result from a diet lacking in vitamin B₁₂ or when intrinsic factor, a substance needed for intestinal absorption of B₁₂, either is not produced by stomach cells or cannot bind to the vitamin. It causes weakness, waxy pallor, shiny tongue, and stomach, intestinal, and neurological problems. Its slow development can allow anemia to become very severe by the time of diagnosis. Monthly B₁₂ injections into muscle soon reverses the anemia, but the injections must be continued for life.

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pernicious anemia [pər′nish·əs ə′nēm·ē·ə]

(medicine)

A megaloblastic macrocytic anemia resulting from lack of vitamin B₁₂, secondary to gastric atrophy and loss of intrinsic factor necessary for vitamin B₁₂absorption, and accompanied by degeneration of the posterior and lateral columns of the spinal cord.