Early sign of Vitamin A deficiency is:

Combined AIIMS - 2020 (Jodhpur, Bhopal, Patna, Raipur)

Applied Nutrition & Dietetics

Easy

Appeared in: Combined AIIMS - 2020 (Jodhpur, Bhopal, Patna, Raipur)

Explanation

Nyctalopia, or night blindness, is the earliest and most specific clinical symptom of Vitamin A deficiency.
Vitamin A (retinal) is a crucial component of rhodopsin, the light-sensitive pigment in the retina's rod cells, which are responsible for vision in dim light.
A lack of Vitamin A impairs the body's ability to synthesize rhodopsin, leading to a longer dark adaptation time and difficulty seeing in low-light conditions.
This initial stage is reversible with Vitamin A supplementation.

Option A: Myopia, or nearsightedness, is a refractive error, not a nutritional deficiency. It occurs when the eye focuses images in front of the retina instead of on the retina.
Option B: Hypermetropia, or farsightedness, is a refractive error where the eye focuses images behind the retina. It is related to the eye's anatomy, not vitamin intake.
Option C: Presbyopia is an age-related condition, typically starting around age 40, caused by the hardening of the eye's lens, which makes it difficult to focus on close objects. It is not caused by a vitamin deficiency.

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Early clinical manifestations of Vitamin A deficiency as background academic context rather than a clinical decision trigger.
Nurses should be aware that night blindness is an early, reversible sign of Vitamin A deficiency and a key indicator for nutritional assessment, especially in at-risk populations like children and pregnant women in developing nations.
Patient education is crucial. A nurse can teach patients and families about dietary sources of Vitamin A (e.g., green leafy vegetables, carrots, mangoes, liver, eggs) to prevent deficiency.
What if? If a child presents with night blindness and it is ignored, the condition can progress to irreversible blindness. The nurse's role includes early identification, reporting, and facilitating prompt treatment with high-dose Vitamin A as per national protocols to prevent permanent corneal damage (keratomalacia).

How to Approach the Question

First, identify the core concept of the question: 'Vitamin A deficiency'.
Next, pinpoint the specific information requested: the 'early sign'.
Recall or deduce the primary functions of Vitamin A, focusing on its well-known role in vision.
Evaluate each option. Myopia, Hypermetropia, and Presbyopia are common eye conditions. Consider their causes. They are primarily structural or age-related (refractive errors).
Consider Nyctalopia. Connect the function of Vitamin A in forming rhodopsin for night vision to the symptom of night blindness.
Conclude that Nyctalopia is the only option directly caused by a lack of Vitamin A and is known to be its earliest manifestation.

Concept Tested & Keywords

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