Vitamin A deficiency

Introduction, Functions of Vitamin A,
Sources of Vitamin A,
Recommended Dietary Allowance,
Clinical manifestation of Vitamin A deficiency,
Assessment of Vitamin A deficiency

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4. Vitamin A deficiency

5. Learning objectives At the end of the class the students should be able to Define the functions of vitamin A List the sources of vitamin A Identify clinical manifestations of Vitamin A deficiency To determine when it is a public health problem and what preventive measures are to be taken 11/14/2021 5 Vitamin A deficiency

6. Contents 11/14/2021 Vitamin A deficiency 6 Introduction Functions of Vitamin A Sources of Vitamin A Recommended Dietary Allowance Clinical manifestation of Vitamin A deficiency Assessment of Vitamin A deficiency

7. Contents 11/14/2021 Vitamin A deficiency 7 Treatment of Vitamin A deficiency Prevention & control of Vitamin A deficiency Summary Exercise

8. Introduction 11/14/2021 Vitamin A deficiency 8 Nutrition may be defined as the science of food and its relationship to health Good nutrition means "maintaining a nutritional status that enables us to grow well and enjoy good health” Nutrients are organic and inorganic complexes contained in food.

9. Introduction 11/14/2021 Vitamin A deficiency 9

10. Vitamin A 11/14/2021 Vitamin A deficiency 10 Belongs to category of micronutrients – required by the body in small amounts Do not yield energy but enables the body to utilize other nutrients Cannot be synthesized by our body & hence has to provided by food Vitamin A includes both retinol & beta carotene

11. Functions For normal vision Necessary for maintaining the integrity and the normal functioning of glandular and epithelial tissue Supports skeletal growth Anti-infective May protect against some epithelial cancers such as bronchial cancers 11/14/2021 11 Vitamin A deficiency

12. Sources ANIMAL FOODS : liver, eggs, butter, cheese, whole milk, fish and meat. PLANT FOODS : green leafy vegetables - spinach and amaranth. Also occurs in most green and yellow fruits & vegetables. Ex papaya, mango, pumpkin, carrots etc FORTIFIED FOODS :Ex: vanaspati, margarine, milk 11/14/2021 12 Vitamin A deficiency

13. Recommended allowances 11/14/2021 Vitamin A deficiency 13 Group Retinol (mcg) B-carotene (mcg) Adults Man 600 4800 Woman 600 4800 Pregnancy 800 6400 Lactation 950 7600 Infants 0 -12 months 350 - Children 1- 6 yrs 400 3200 7 - 12 yrs 600 4800 Adolescent 13 -19 yrs 600 4800

14. Deficiency 11/14/2021 14 Vitamin A deficiency

15. Night blindness Inability to see in dim light. Due to impairment in dark adaptation. 11/14/2021 15 Vitamin A deficiency

16. Conjunctival xerosis First clinical sign of vitamin A deficiency. Conjunctiva becomes dry and non- wettable Described as "emerging like sand banks at receding tide” 11/14/2021 16 Vitamin A deficiency

17. Bitot's spots Triangular, pearly-white or yellowish, foamy spots on the bulbar conjunctiva on either side of the cornea, frequently bilateral. Indication of In young children In older individuals 11/14/2021 17 Vitamin A deficiency

18. Corneal xerosis 11/14/2021 Vitamin A deficiency 18 Cornea appears dull, dry, non wettable & eventually opaque. In more severe deficiency - corneal ulceration. Ulcer may heal leaving a corneal scar which can affect vision.

19. Keratomalacia 11/14/2021 Vitamin A deficiency 19 Liquefaction of the cornea Is a grave medical emergency. The cornea may become soft and may burst open. If the eye collapses, vision is lost. It’s one of the major causes of blindness in India and is frequently associated with protein energy malnutrition.

20. EXTRA-OCULAR MANIFESTATIONS 11/14/2021 Vitamin A deficiency 20 Comprise follicular hyperkeratosis, anorexia and growth retardation which have long been recognised. They are non-specific and difficult to quantify. Even mild vitamin A deficiency causes an increase in morbidity and mortality due to respiratory and intestinal infection

21. Assessment of Vitamin A deficiency Population surveys employing both clinical & biochemical criteria using prevalence criteria by WHO 11/14/2021 21 Vitamin A deficiency Criteria Prevalence in population at risk (6 months -6 years) Night blindness >1 % Bitot spots > 0.5% Corneal xerosis > 0.01% Corneal ulcer >0.05% Serum retinol (< 10 mcg/dl) > 5%

22. Treatment of Vitamin A deficiency Two doses of 2 lakh I.U of vitamin A are given 4 weeks apart according to the NPCB. However, WHO recommends another dose that should be given on 2 nd day after the first dose [so totally 3 doses are given] 11/14/2021 22 Vitamin A deficiency

23. Prevention and control of Vitamin A deficiency SHORT TERM ACTION: Vitamin A administration according to Indian National Immunization Schedule MEDIUM TERM ACTION: Fortification of certain foods with vitamin A. Ex: addition of Vit A to dalda 11/14/2021 23 Vitamin A deficiency At 9 months along with measles 1 lakh IU At one and a half year with DPT booster 2 lakh IU 1-5 yr 2 lakh IU every 6 monthly

24. Prevention and control of Vitamin A deficiency contd …. 11/14/2021 24 Vitamin A deficiency LONG TERM ACTION: Improvement of people’s diet Promote breast feeding for as long as possible. Improvements in environmental health – ensuring safe & adequate water supply; construction and maintenance of sanitary latrines Immunization against infectious diseases such as measles

25. Summary Vitamin A is one of the fat soluble vitamins Has an important role in production of retinal pigments Richest source- carrots & halibut liver oil RDA Deficiency results in xerophthalmia Treatment Prevention & control 11/14/2021 25 Vitamin A deficiency

26. References & Further reading Park K. Park’s Textbook of Preventive and Social Medicine,22 nd ed. Jabalpur: Banarsidas Bhanot;2013 National program for control of blindness (NPCB) 11/14/2021 26 Vitamin A deficiency

27. Exercise An epidemiological survey conducted among 500 children aged between 6 months to 6 years revealed that 5 children had bitots spots, 10 children had conjuctival xerosis, 20 had night blindness. What is your inference and list the measures you will take based on your inference. 11/14/2021 27 Vitamin A deficiency

28. Thank you 11/14/2021 28 Vitamin A deficiency