The deficiency of vitamin B12 results in?

UPRVUNL - 2021

Applied Nutrition & Dietetics

Easy

Appeared in: UPRVUNL - 2021

Explanation

Pernicious anemia is a specific type of megaloblastic anemia that is the most characteristic clinical manifestation of Vitamin B12 deficiency.
It is caused by an autoimmune process that leads to the destruction of gastric parietal cells, which secrete Intrinsic Factor (IF).
Without Intrinsic Factor, the body cannot absorb dietary Vitamin B12, leading to impaired DNA synthesis and the production of large, immature red blood cells (megaloblasts).

Option A: Inflammation of the skin and eyes is not a primary sign of Vitamin B12 deficiency. These symptoms are classically associated with Vitamin B2 (Riboflavin) deficiency.
Option B: Night blindness (nyctalopia) is the hallmark symptom of Vitamin A deficiency, as Vitamin A is a crucial component of rhodopsin, the pigment in retinal rod cells.
Option C: While loss of coordination (ataxia) is a serious neurological symptom of Vitamin B12 deficiency due to demyelination, pernicious anemia is the primary, named disease state caused by the deficiency.

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Clinical manifestations of Vitamin B12 deficiency as background academic context rather than a clinical decision trigger.
Nurses must be vigilant in identifying patients at risk for B12 deficiency, including the elderly, strict vegans, and patients with a history of gastrectomy or malabsorption syndromes like Crohn's disease.
A critical nursing consideration is that administering folic acid alone to a patient with megaloblastic anemia can mask a B12 deficiency. While the anemia may improve, the folic acid will not prevent the progression of irreversible neurological damage.
Patient education is key, especially for those with pernicious anemia who require lifelong B12 supplementation, typically via intramuscular injections, as they cannot absorb it orally.

How to Approach the Question

First, identify the core concept of the question, which is the result of a specific nutrient deficiency (Vitamin B12).
Scan the options to see the different conditions listed.
Recall the primary diseases associated with major vitamin deficiencies. Link Vitamin B12 to anemia and neurological issues.
Differentiate between a primary disease diagnosis and a symptom. Both 'Loss of coordination' and 'Pernicious anemia' are related to B12 deficiency.
Recognize that 'Pernicious anemia' is the specific, named disease entity, whereas 'loss of coordination' is one of several possible neurological symptoms. In medical questions, the primary disease is usually the better answer over a single symptom.
Eliminate the other options by linking them to their correct vitamin deficiencies (Vitamin A for night blindness, Vitamin B2 for skin/eye issues).

Concept Tested & Keywords

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