VITAMIN A DEFICIENCY BY: SUMAYYA NASEEM INTERNEE OPTOMETRIST
Vitamin A - Needed everywhere.Vitamin A is one of a group of fat soluble vitamins that are essentialfor 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, Whipples disease, Crohns 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• Sjogrens 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 XerophthalmiaPrimary signsX1A Conjunctival XerosisX1B Bitot’s spots with conj. xerosisX2 Corneal XerosisX3A Corneal ulceration & XerosisX3B KeratomalaciaSecondary signsXN Night BlindnessXF Xerophthalmic FundusXS Xerophthalmic Scars
Signs of XerophthalmiaTop left: Bitots 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.
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
TREATMENT1. 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 200,000 IU vit.A orally (Day 1) The following day 200,000 IU vit.A orally (Day 2) Four weeks later 200,000 IU vit.A orally (Week 4)
W.H.O.’s recommended doses (for treatment of children under 1 year of age or <8 kg)Immediately on diagnosis 100,000 IU vit.A orally (Day 1) The following day 100,000 IU vit.A orally (Day 2) Four weeks later 100,000 IU vit.A orally (Week 4)
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
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 tothe child•Liver, egg, cheese, butter, fish liver oil etc aregood sources of vitamin A.5. Immunization • Measles5. Avoid traditional healers • Herbs • Tooth paste etc