1.42k likes | 7.21k Views
Xerophthalmia. Literaly means “dry eye” Ocular abnormalities from vitamin A deficiency (nutritional deficiency) Include night blindness, conjunctival and corneal xerosis, corneal ulceration and melting If in severe stage will have liquefactive corneal necrosis (Keratomalacia). Causes.
E N D
Xerophthalmia • Literaly means “dry eye” • Ocular abnormalities from vitamin A deficiency (nutritional deficiency) • Include night blindness, conjunctival and corneal xerosis, corneal ulceration and melting • If in severe stage will have liquefactive corneal necrosis (Keratomalacia)
Causes • Vitamin A deficiency • Protein malnutrition • systemic diseases • Eg. Sjogren' s syndrome, SLE, rheumatoid arthritis, scleroderma, sarcoidosis, amyloidosis, hypothyroidism • medications • antihistamines, nasal decongestants, tranquilizers, and anti-depressant drugs
Epidemiology • 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 TARGET TISSUE Photoreceptor, Epithelial tissue GUT Absorp 50-90% retinol BLOOD LIVER + retinal binding protein Retinyl palmitate
FUNCTIONS • Gene expression • Epithelial cell differentiation • Normal growth • Photopic vision • Immune function • Antioxidant
Clinical Features Vitamin A Deficiency
Clinical Features • Night Blindness • Difficulty seeing in the dark. Abnormal dark adaptation • Xerosis (Dry Eyes) • The white of the eye loses its shine and begins to wrinkle. • Bitot's Spots • Patches of little gray bubbles on the whites of the eye. • Corneal Ulceration • Dullness or damage to the cornea. • Keratomalcia • Soft or bulging cornea.
require some time for their eyes to adjust from brightly lit areas to dim ones. Contrast vision may also be greatly reduced.
Corneal changes Corneal punch-out lesion
Keratomalacia • 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 • Vitamin A orally is given. May be given by intramuscular injection also and repeated. • Correct malnutrition • 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. • Vitamin A must be administered orally immediately upon diagnosis.
For treatment of xerophthalmia according to the schedule shown below.
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.
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.
Drug of choice • 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 • Short-term • High dose VIT A supplement • VIT A supplement can reduce child mortality by 34% • VIT A supplement is on the most cost-effective prevention • Distributed by health facilities or teams
Medium-term • 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