Vitamin A Deficiency (VAD) is a micronutrient deficiency disorder resulting from inadequate body stores of retinol. It primarily affects the eyes, epithelial tissues, immune system, and growth processes. The condition is most common among children aged 6 months to 5 years, pregnant women, and populations with chronic malnutrition.

Vitamin A is essential for:

• Vision (especially night vision through rhodopsin formation)

• Epithelial integrity of skin and mucous membranes

• Immune defense against infections

• Growth and development

• Reproduction

Untreated VAD is the leading preventable cause of childhood blindness worldwide and significantly increases mortality, particularly in children with measles or persistent diarrhoea.

2. Pathophysiology

Vitamin A exists in three biologically active forms:

Deficiency leads to:

1. Failure of rhodopsin synthesis → night blindness

2. Keratinization of epithelial tissues → xerosis

3. Corneal destruction → keratomalacia → blindness

4. Reduced mucosal immunity → recurrent infections

3. Risk Factors

Nutritional

• Protein-energy malnutrition

• Low intake of animal products

• Lack of dietary fat

• Early cessation of breastfeeding

• Poor complementary feeding

Infectious diseases

• Measles

• Persistent diarrhoea

• Intestinal parasites

• HIV infection

• Tuberculosis

Maternal factors

• Maternal malnutrition

• Poor breastfeeding practices

Socioeconomic

• Poverty

• Food insecurity

• Limited nutrition education

4. Clinical Features

Ocular Manifestations (Xerophthalmia Spectrum)

Signs and Symptoms

• Night blindness

• White foamy patches on eye (Bitot’s spots)

• Conjunctival dryness

• Corneal dryness and wrinkling

• Corneal ulceration

• Keratomalacia (softening of cornea)

• Photophobia

• Recurrent infections

• Poor growth

• Dry rough skin (follicular hyperkeratosis)

5. Diagnostic Criteria

Diagnosis is primarily clinical.

A child is considered to have VAD if ANY of the following are present:

• Night blindness

• Bitot’s spots

• Corneal xerosis

• Keratomalacia

• Corneal ulcer

• History of measles with malnutrition

6. Investigations

(Usually not required in low-resource settings)

7. Management

Goals

1. Prevent blindness

2. Reduce mortality

3. Restore epithelial integrity

4. Improve immunity

A. Non-Pharmacological Management

Dietary Supplementation

Encourage intake of vitamin-A-rich foods:

Plant Sources (Pro-vitamin A carotenoids)

• Carrots

• Sweet potatoes

• Mangoes

• Pawpaw

• Pumpkin

• Dark green leafy vegetables (spinach, matembele, mnafu)

• Broccoli

• Apricots

• Melon

Animal Sources (Preformed Vitamin A – Best absorbed)

• Liver

• Eggs

• Full cream milk

• Fish

• Fortified margarine

• Fortified maize meal and bread

B. Pharmacological Management

1. Prophylaxis (Routine Supplementation)

Give every 6 months up to 5 years

2. Treatment (Therapeutic Dosing)

Indications:

• Clinical VAD

• Measles

• Persistent diarrhoea

• Severe malnutrition

Dosing Schedule (Day 1, Day 2, Day 14)

Administration Procedure

1. Cut narrow end of capsule

2. Open child’s mouth gently

3. Squeeze contents into back of mouth

4. Repeat dose if vomited immediately

Important Notes

• Do NOT give caregiver capsule to take home

• Wait ≥1 month between doses

• Do not repeat treatment if prophylaxis given in past month

• Multivitamin syrup does NOT replace therapeutic dosing

8. Monitoring

9. Complications

• Irreversible blindness

• Corneal perforation

• Secondary infections

• Growth failure

• Increased mortality (especially measles)

10. Prevention

Public Health Measures

• Routine supplementation programs

• Food fortification

• Measles vaccination

• Deworming programs

• Nutrition education

Individual Prevention

• Exclusive breastfeeding for 6 months

• Adequate complementary feeding

• Balanced diet

11. Prognosis

• Excellent if treated early

• Corneal disease → permanent blindness

• Mortality risk reduced by up to 24% after supplementation