PREPARED BY DR GEORGE DEOGRATIAS

1. VITAMIN A DEFFICIENCY
Prepared by
George deogratias MD5 student.
Archbishop James university college the constitute of
st.augustine university of Tanzania.
(biziriko1991@gmail.com)
+255656592079
03/25/181

2. Cont…
 Vitamin A is a broad term for a number of
similar compounds , First recognized fat
soluble vitamin
 Two forms :
a) Preformed vitamin A: retinoids ( from
animals)
b) Provitamin A: carotenoids
(predominantly beta carotene from
plants)
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Dr george
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3. CONT…
Preformed vitamin A: Retinoids
 Active or usable form
 Four categories of retinoids:
a) retinol (b) retinal
c) retinoic acid (d) retinyl esters
All retinoids are absorbed as retinol.
Sources: animal products like liver, fish , fish
oils ,
milk , eggs etc.
 Liver is richest source
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Dr george
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4. Cont…
 ProvitaminA: Carotenoids
 Precursor of vitamin A
 Predominantly beta carotene
 Body has to convert it into active vitamin
A after
 consumption
 Sources: plant products like carrot , green
leafy
 vegetables , papaya , mango , bringal.
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george
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5. Functions of Vitamin A
(Retinol)
 Vitamin A is essential to the normal
structure and function of the skin and
mucous membranes
 It is also required for cell differentiation
and therefore for normal growth and
development
 For normal vision
 For the immune system.
03/25/185

6. Cont…
 Important in wound healing, bone
formation (e.g., teeth), healthy skin and
growth and lactation.
 Further, it may also be a factor in
preventing cancers.
 It has been shown to have antiviral
properties.
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7. Metabolism
 Normally, the liver stores 80 to 90% of
the body's vitamin A.
 To use vitamin A, the body releases it
into the circulation bound to
prealbumin (retinol-binding protein)
 β-Carotene and other provitamin
carotenoids, contained in green leafy
and yellow vegetables and deep- or
bright-colored fruits, are converted to
vitamin A.
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8. VITAMIN A DEFICIENCY-
CAUSES;
 Inadequate intake-
 Fat malabsorption- sprue, cystic fibrosis,
pancreatic insufficiency, duodenal
bypass, chronic diarrhea, bile duct
obstruction, giardiasis
 liver disorders -cirrhosis
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9. XEROPHTHALMIA
 General term applied to all the ocular
manifestations of impaired vitamin A
metabolism, from night blindness through
complete corneal destruction
 Xeros – dry
 ophthalmia – eye
 literally means “ dry eye “
 conventionally xerophthalmia has become
synonymous
 with vitamin A deficiency
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Dr george
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10. WHO Classification of
xerophthalmia
 XN (Night blindness)
 X1A ( Conjunctival xerosis)
 X1B ( Bitot’s spots)
 X2 ( Corneal xerosis)
 X3A ( Corneal ulceration/Keratomalacia affecting
less than one third corneal surface)
 X3B ( Corneal ulceration/Keratomalacia affecting
more than one third corneal surface)
 XS ( Corneal scars)
 XF ( Xerophthalmic fundus)
 Biochemical criterion: Plasma vitamin A < 0.35
μmol/L
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11. Cont…
 Is a major cause of preventable blindness in
children and especially in developing countries
 It is an inflammation of the cornea that is
associated with nutritional deficiency
 Risk factors-
 general malnutrition, diarrhea, measles, HIV/AIDS,
failure to thrive, lack of food diversity
 Although xerophthalmia is most prevalent with
children, it can also occur in adults with severe
malnutrition or in other health problems in which
lack of vitamin A in their diets is a factor.
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12. Cont…
 Night blindness, is an early symptom
 Superficial foamy patches composed of
epithelial debris and secretions on the
exposed bulbar conjunctiva (Bitot's spots
 It involves drying (xerosis) and thickening
of the conjunctivae and corneas.
 cornea erosions- keratomalacia
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13. Other systems
 There is keratinization of Skin, drying,
scaling, and follicular thickening of the
skin
 Mucous membranes disorders in the
respiratory, GI, and urinary tracts can
occur- infections
 Immunity is generally impaired
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14. Bitot spots
The Bitot’s spot is a
raised, silvery white, foamy, triangular patch
of
keratinised epithelium, situated on the
bulbar conjunctiva in the inter-palpebral
area
Note; usually bilateral and temporal, and
less frequently nasal.
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15. Corneal Xerosis
 The earliest change in the cornea is
punctate keratopathy .
 which begins in the lower nasal quadrant,
followed by haziness and/or granular
pebbly dryness
 Involved cornea lacks lustre.
Dr george deogratias
03/25/18
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16. XFC (Xerophthalmic fundus)
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 It is characterized by
 typical seed-like, raised, whitish lesions
scattered uniformly over the part of the
fundus at the level of optic disc

17. Treatment-Xerophthalmia
 Apply an antibiotic -to prevent
secondary bacterial infection.
Ointment, e.g. tetracycline or
chloramphenicol
 Protect the eye with an eye shield in
order to prevent trauma.
 Vitamin A must be administered orally
immediately upon diagnosis-
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18. Treatment
 50,000 IU for infants < 6 mo, 100,000 IU
for infants 6 to 12 mo,
 200,000 IU for children > 12 mo and
adults should be given for 2 days; with
a third dose at least 2 wk later.
 For pregnant or lactating women,
prophylactic or therapeutic doses
should not exceed 10,000 IU /day to
avoid possible damage to the fetus or
infant
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19. Cont…
 A. MEDICAL
 Antibiotcs, Mydiatrics
 Pad specially in X3A, X3B
 Avoid Exposure: Antibiotic Ointment
 Methyl Cellulose Drops
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20. Cont…
B. SURGERY
1. Conjunctivoplasty
2. Keratoplasty
a. Prophylactic
b. Optical
REHABILITATION
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Dr george
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21. Prevention
 Improve diet- dark green leafy vegetables,
deep- or bright-colored fruits (eg, papayas,
oranges), carrots, and yellow vegetables (eg,
squash, pumpkin).
 Vitamin A–fortified milk and cereals, liver, egg
yolks, and fish liver oils are helpful.
 Carotenoids are absorbed better when
consumed with some dietary fat.
 Prophylactic supplements of vitamin A
palmitate in oil 60,000 RAE (200,000 IU) po every
6 mo- for all children between 1 - 5 years of
age; infants < 6 mo-1year can be given a one-
time dose of 15,000 RAE (50,000-100,000 IU),
03/25/1822

22. Vitamin A Toxicity
 Accidental ingestion by children-more
than 300,000IU
 or chronic
 It usually occurs by taking more that 50,000 IU per
day for more than 3 months.
 It can lead to dry skin, mouth sores, vomiting, and
poor appetite.
 Eventually, it can cause increased pressure within the
brain, headaches, and problems thinking clearly. It
may also lead to an enlarged liver or to liver failure.
 There is evidence that high levels of retinol may
increase the risk of birth defects.
03/25/1823

23. ,
Ahsanteni sana
03/25/18
Dr george deogratias
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