Vitamin A Deficiency (VAD)

Notes

## Basic introduction

  • VAD is a major nutritional concern in the low-income countries.
  • VAD is one of the most important causes of preventable childhood blindness globally
  • It is a major contributor to morbidity and mortality from infections in low- and middle-income countries
  • VAD occurs mostly in the last trimester of pregnancy due to high demand by both the unborn child and the mother.

## Some physiological roles of vitamin A include:

  • Normal functioning of the visual system
  • Maintaining cell functions to promote growth
  • Production of RBCs
  • Development of immunity (VAD causes reduction in lymphocyte response that leads to reduced secretory IgA levels in mucous membranes)
  • Reproduction

## Risk factors for VAD

  • Poverty
  • Lack of an adequate intake of vitamin A
  • Exposures to infections
  • Diarrhea
  • Measles
  • Interference with absorption, storage, or transport of vitamin A (e.g. pancreatic insufficiency, duodenal bypass, chronic diarrhea, bile duct obstruction, giardiasis, in celiac disease, cystic fibrosis, and cirrhosis)

## Food rich in Vitamin A

  • Dark green leafy vegetables
  • Deep- or bright-colored fruits such as papayas and oranges
  • Carrots
  • Yellow vegetables such as squash and pumpkin
  • Liver
  • Egg yolks
  • Whole milk
  • Animal butter
  • Whole small fish

## Statistics

  • Globally, night blindness affects 5.2 million pre-school age children and 9.8 million pregnant women corresponding to 0.9% and 7.8% of the population at risk of VAD.
  • Globally, low serum retinol concentration (<0.70 µmol/l) affects an estimated 190 million pre-school age children and 19.1 million pregnant women corresponding to 33.3% of the preschool-age population and 15.3% of pregnant women in populations at risk of VAD.
Symptoms

## Ophthalmological symptoms

  • Night blindness
  • Keratomalacia (thinning and ultimately ulceration of the cornea
  • Foreign body sensation
  • Bitot's spots (areas of abnormal squamous cell proliferation and keratinization of the conjunctiva, causing oval, triangular or irregular foamy patches on the white of the eye)
  • Conjunctival dryness
  • Corneal dryness
  • Corneal ulcer/perforation
  • Xerophthalmia
  • Blindness

Other symptoms

  • Severe anemia
  • Wasting
  • Follicular hyperkeratosis
  • Dry skin
  • Dry hair,
  • Pruritus
  • Broken fingernails
  • Increased susceptibility to infections

Increased risk of mortality

Diagnosis
  • Clinical review (especially ocular manifestations of xerophthalmia)
  • Plasma or serum retinol concentrations (<0.70 µmol/l)
  • Response to administration of vitamin A
  • Serum zinc level (as zinc deficiency can interfere with production of retinol-binding protein)
  • FBC
  • Renal function tests
  • LFTs
Differential
  • Hypothyroidism
  • Zinc deficiency
  • Atrophia Maculosa
  • Keratosis Follicularis
  • Keratosis Pilaris
  • Lichen Nitidus or Planus or Simplex Chronicus or Spinulosus or Striatus
  • Perforating Folliculitis
  • Pityriasis Rubra
  • Varioliformis Cutis
Prevention
  • Dietary diversification
  • Vitamin A supplementation
  • Vitamin A fortification
  • Addressing national socioeconomic challenges
  • Nutrition education
Reference

1. Akhtar, S, Ahmed, A, Randhawa MA, Atukorala S, Arlappa N, Ismail T, Ali Z (2013) Prevalence of vitamin A deficiency in South Asia: causes, outcomes, and possible remedies. J Health Popul Nutr. 2013 Dec; 31(4): 413–423.

2. Kenyan Ministry of Health. Clinical guidelines for management and referral of common conditions at levels 4-6. Hospitals. 2009; 3:259-261.http://apps.who.int/medicinedocs/documents/s21000en/s21000en.pdf

3. Ministry of Health, Kenya. Kenya Essential Medicine List (2016). http://publications.universalhealth2030.org/uploads/KEML-2016Final-1.pdf

4.World Health Organization. Global prevalence of vitamin A deficiency in populations at risk 1995-2005: WHO global database on vitamin A deficiency. Geneva: World Health Organization; 2009. p. 55.

Management
  • Vitamin A supplement 200,000IU once every 6 months, starting at 6 months to 5 years.
  • Measles immunization
  • Management of complications from VAD
Drug Index 2.0 is here
Our new update features a more powerful search feature and easier login. Having any issues? Contact us today. Contact Us