Transcript ภาพนิ่ง 1 - Chiang Mai University

Xerophthalmia
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Literaly means “dry eye”
Ocular abnormalities from vitamin A
deficiency (nutritional deficiency)
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Include night blindness, conjunctival and
corneal xerosis, corneal ulceration and
melting
If in severe stage will have liquefactive
corneal necrosis (Keratomalacia)
Causes
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Vitamin A deficiency
Protein malnutrition
systemic diseases
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Eg. Sjogren' s syndrome, SLE, rheumatoid
arthritis, scleroderma, sarcoidosis, amyloidosis,
hypothyroidism
medications

antihistamines, nasal decongestants,
tranquilizers, and anti-depressant drugs
Epidemiology
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Remains a worldwide problem especially
in the developing countries
peak incidence is 3-5 years of age
associated with vitamin A deficiency and
malnutrition in general
METABOLISM
FOOD
GUT
TARGET
TISSUE
Photoreceptor,
Epithelial tissue
Absorp 50-90% retinol
LIVER
Retinyl palmitate
BLOOD
+ retinal binding
protein
FUNCTIONS
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Gene expression
Epithelial cell differentiation
Normal growth
Photopic vision
Immune function
Antioxidant
Clinical Features
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Night Blindness
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Xerosis (Dry Eyes)
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Patches of little gray bubbles on the whites of the eye.
Corneal Ulceration
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The white of the eye loses its shine and begins to
wrinkle.
Bitot's Spots
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Difficulty seeing in the dark. Abnormal dark adaptation
Dullness or damage to the cornea.
Keratomalcia
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Soft or bulging cornea.
Night blindness
require some time for their eyes to adjust
from brightly lit areas to dim ones. Contrast vision
may also be greatly reduced.
Xerosis (Dry Eyes)
Marked conjunctival
and corneal xerosis
Bitot's Spots
Corneal changes
Corneal punch-out lesion
Corneal Ulceration
Corneal scar
Keratomalacia
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Liquefaction of part or all of the
cornea, leading to rupture, with
extrusion of the eye contents and
subsequent shrinking of the globe
(phthisis bulbi), or to anterior bulging
(corneal ectasia and anterior
staphyloma) and blindness.
Diagnosis
Most -clinical diagnosis
Laboratory tests (Unusual)
A serum retinol study
- costly but direct measure
- high-performance liquid chromatography
- >20 mg/dl : adequate
- <10 mg/dl : grossly deficient
- plasma vitamin A level or <0.35 mmol/L
- <0.7 mg/L in children younger than 12 years is
considered low
-
respect to light and temperature
Total retinol binding protein
- easier to perform and less expensive
- detected by an immunologic assay.
- more stable compound than retinol
- less accurate because they are affected by serum
protein concentrations
- zinc deficiency interferes with RBP production
Conjunctival impression
cytology
histologic appearance of superficial
epithelial layers
- Conjunctival xerosis -The epithelium is
characterized by keratinization
- Keratomalacia - Stromal necrosis is
covered by keratinized epithelium
-
conjunctival xerosis : The epithelium is characterized by keratinization,
a prominent granular cell layer, and distended
squamous cells with large, open nuclei and
prominent nucleoli.
Keratomalacia : The sharply demarcated area of stromal necrosis is
covered by keratinized epithelium
Treatment
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Vitamin A orally is given. May be given by intramuscular
injection also and repeated.
Correct malnutrition
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Diet: Plenty of milk, butter, dark green leafy vegetables,
carrots, orange, cod-liver oil required.
Topical lubrication and retinoic acid may be use as
adjunctive
If infection is present in eyes - antibiotic ointment may
be applied.
Emergency Patient Care

In order to treat or prevent a secondary bacterial
infection, which would compound corneal damage.
Apply an antibiotic eye ointment, e.g. tetracycline or
chloramphenicol.
 Protect the eye with an eye shield in order to prevent trauma.
 In the case of young children, it may be necessary to restrain
arm movements while applying the shield.
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Vitamin A must be administered orally immediately upon
diagnosis.
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For treatment of xerophthalmia according to the schedule
shown below.
Timing
Immediately on diagnosis
Next day
Within 2-4 weeks
Severe protein energy
malnutrition
Monthly until PEM resolved
<1 year of age
(IU)
100,000
≥1 year of age
(IU)
200,000
100,000
100,000
200,000
200,000
100,000
200,000
Treatment : Women with
Xerophthalmia
Women of reproductive age require special attention
because of the potential teratogenic effects of very high
dose retinol early in pregnancy
 Women of reproductive age with night blindness or
Bitot's spots should be treated with

A daily oral dose of 5,000-10,000 IU of vitamin A for at least
4 weeks.
 Such a daily dose should never exceed 10,000 IU, although
a weekly dose not exceeding 25,000 IU may be substituted.
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All women of reproductive age, whether or not
pregnant, who exhibit severe signs of xerophthalmia
(i.e. acute corneal lesions) should be treated with three
dose treatment.
Immediately on
diagnosis
200,000IU
Next day
2 weeks later
200,000IU
200,000IU
Drug of choice
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Retinol palmitate, 110 mg or
Retinol acetate , 66 mg
→ 200,000 IU Vit.A
oral, immediately and again the following day
Additional dose every 1-2 week to restore liver
reserve.
Parenteral replacement essential Retinol acetate
100,000 IU in 55 mg water can replace first oral
dose.
Correct protein energy malnutrition
Prevention
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Short-term
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High dose VIT A supplement
VIT A supplement can reduce child mortality
by 34%
VIT A supplement is on the most costeffective prevention
Distributed by health facilities or teams
Vitamin A prophylaxis schedule
Age
Dose (IU)
Infants (0-6 mo.)
25,000
Children (6-12 mo.)
100,000
Children (>12 mo.)
200,000
Woman (postpartum)
200,000
Pregnant and lactating woman
5-10,000
Timing
1-3 times
Once every
4-6 months
Once every
4-6 months
Within 1 month of
delivery
Daily
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Medium-term
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Introducing food
fortified with VIT A
such as milk, tea,
cereal
•Long-term
- Improve socioeconomic level
- Improve health and nutrition
education
THANK YOU
FOR YOUR ATTENTION