Vitamin A Deficiency

Question 1

Define Vitamin A deficiency?

Answer 1

Causes XEROPHTHALMIA (ocular mainfestations)

Question 2

Why do we need Vitamin A?

Answer 2

Vitamin A is required for formation of rhodopsin, photoreceptor pigment in the retina

Question 3

What is Vitamin A deficiency due to?

Answer 3

Inadequate intake
Fat malabsorption
Liver disorders (Liver stores vit A)

Question 4

What happens in xerophthalmia?

Answer 4

There is dryness of the conjuctiva and cornea due to keratinisation of the eyes

Question 5

What does Conjunctivae lead to?

Answer 5

Oval/triangular spots (Bitots spots) and cornea becomes cloudy and soft

Question 6

What is the epidemiology of Vitamin A deficiency?

Answer 6

Common in Southern and Eastern Asia where rice is the staple food - rice is devoid of beta carotene (precursor to vit A)
Rare in UK

Question 7

What are the presenting symptoms of Vitamin A deficiency?

Answer 7

Starts off with night blindness
As diseases progresses, cornea becomes hazy and can develop erosions which can lead to its destruction and complete blindness
Can also get drying, scaling and follicular thickening of the skin due to keratinisationa of skin
Respiratory infections due to keratinisation of mucous membranes in respiratory tract

Question 8

What are the signs of Vitamin A deficiency?

Answer 8

Night blindness, which may cause injuries
Conjunctival xerosis - dry, dull and thick
Bitots spots on conjunctiva
Corneal xerosis - cornea appears dry and dull
Corneal ulcerations
Keratomalacia - late stage of xerophthalmia - softening of cornea, followed by perforation of eyeball and blindness
Dry skin
Dry hair
More prone to infection

Question 9

What investigations do you do for Vitamin A deficiency?

Answer 9

Check sight in darkness
Serum retinol binding protein
Zinc levels - zinc deficiency can interfere with production of retinol-binding protein
Iron studies - can affect metabolism of vitamin a
FBC: for anaemia or infection

Question 10

What is the management plan for Vitamin A deficiency?

Answer 10

Treat with Vitamin A supplements
Re-educate and monitor diet
High Vit A- chicken, eggs, leafy green veg

Question 11

What are the possible complications of Vitamin A deficiency?

Answer 11

Blindness

Respiratory infections

Question 12

What is the prognosis for patients with Vitamin A deficiency?

Answer 12

Good if treated early, before blindness progresses