vitamin a deficiency

VITAMIN A DEFICIENCY

BY: SUMAYYA NASEEMINTERNEE OPTOMETRIST

Vitamin A - Needed everywhere.

Vitamin A is one of a group of fat soluble vitamins that are essential for life and health. Three active forms: retinol, retinal and retinoic.

Vitamin A plays a critical role in:•Vision (A is part of rhodopsin, the visual pigment)

•Epithelial tissues need to protect integrity.•Growth •Reproduction •Pattern formation during embryogenesis •Bone development •Brain development •Immune system function

Deficiency Diseases: Keratinization, xerosis, Xerophthalmia, Infections, Weak bones, poor teeth.

• Vitamin A deficiency is a preventable cause of blindness.• It is a well-known cause of blindness and is associated with elevated

mortality among infants and children. • People most at risk are children between six months to six years,

pregnant women, and lactating women. • One of the main causes of Xerophthalmia is the poor intake of vitamin A,

this disease is also associated with:

Faulty feeding habits Mal absorption syndromes (cystic fibrosis, Whipple's disease, Crohn's

disease, ulcerative colitis, short bowel syndrome, gastroenteritis, measles)

Pancreatic disease Chronic liver disease Weight Loss Surgery Poverty Ignorance

and some other conditions among the entire population, but mainly in developing countries and in young children all over the world in particular.  

Xerophthalmia• Xerophthalmia (Greek for dry eyes) is a medical condition in which the

eye fails to produce tears. It may be caused by a deficiency in vitamin A and is sometimes used to describe that lack, although there may be other causes.

Other causes include:

• Hypothyroidism• Rheumatoid arthritis• Sarcoidosis• Scleroderma• Sjogren's syndrome• Systemic lupus erythematosus• Drugs

– Antihistamines– Nasal decongestants– Tricyclic antidepressants

• Conjunctivitis• Keratoconjunctivitis• Keratoconjunctivitis sicca

• Xerophthalmia caused by a severe vitamin A deficiency is described by pathologic dryness of the conjunctiva and cornea. The conjunctiva becomes dry, thick and wrinkled. If untreated it can lead to corneal ulceration and ultimately in blindness.

• Xerophthalmia is a term that usually implies a destructive dryness of the conjunctival epithelium due to dietary vitamin A deficiency — a rare condition in developed countries, but still causing much damage in developing countries. Other forms of dry eye are associated with aging, poor lid closure, scarring from previous injury, or autoimmune diseases. 

Classification of Xerophthalmia

Primary signsX1A Conjunctival XerosisX1B Bitot’s spots with conj. xerosisX2 Corneal XerosisX3A Corneal ulceration & XerosisX3B Keratomalacia

Secondary signsXN Night BlindnessXF Xerophthalmic FundusXS Xerophthalmic Scars

Dryness & Bitot's spot

Signs of Xerophthalmia

Top left: Bitot's spotTop right: Cornea with typical dry appearance and ulcer stained green with fluorescein dye; Bottom right: Corneal scarring; Bottom left: Deep corneal ulceration progressing towards keratomalacia.

Keratomalacia

Symptoms

• Night Blindness (poor vision at night or in dim light)

• Extreme dryness of the eyes • Dry, foamy & silver-gray deposits on bulbar

conjunctiva• Wrinkling, progressive cloudiness of corneas.

Other factors involved in Xerophthalmia

Protein energy malnutrition (PEM) Generalized infections (measles, malaria,

gastroenteritis)

Exposure ulcers Herpes simplex Intestinal parasites Treatment from traditional healers

TREATMENT

1. Nutritional and general treatment2. Topical treatment to the eye3. Surgery

W.H.O.’s recommended doses (for treatment of children over 1 year of age)

Immediately on diagnosis (Day 1)

200,000 IU vit.A orally

The following day(Day 2)

200,000 IU vit.A orally

Four weeks later(Week 4)

200,000 IU vit.A orally

W.H.O.’s recommended doses (for treatment of children under 1 year of age or <8 kg)

Immediately on diagnosis (Day 1)

100,000 IU vit.A orally

The following day(Day 2)

100,000 IU vit.A orally

Four weeks later(Week 4)

100,000 IU vit.A orally

NOTE• Preventive doses of vitamin A are also

given to pregnant women and those who are breast feeding. But small daily doses than one massive dose. The reason is to prevent any possibility of a massive dose of vitamin A being teratogenic to fetus.

• If massive dose is not available, then child should eat food rich in vitamin A.

Topical treatment to the eye

• Antibiotics• Antiviral agents• Padding an eye• Closing the eyes• Mydriatics• No steroids

Surgery

• Corneal Grafting• Conjunctival flaps

Prevention1. Distribution of massive dose

capsules (with polio vaccine)

2. Food Fortification (to improve nutrition by enriching commonly-used food products with important vitamins and minerals)

» Cooking Oil » Wheat Flour

3. Horticulture and agriculture Green leafy vegetables Orange colored fruits &

vegetables

l

Man fortifying oil in Mali

Fortified milk

4. Nutrition & health education• Radio• TV• School etc.

Mothers will need advice about: •Breast feeding•Weaning in general •How to prepare them, E.g. giving fried egg to the child •Liver, egg, cheese, butter, fish liver oil etc are good sources of vitamin A.

5. Immunization• Measles

5. Avoid traditional healers• Herbs• Tooth paste etc