Micronutrient deficiencies

Definition of Micronutrient Deficiencies

Deficiencies of minerals (iron, iodine, zinc, calcium, phosphorus, magnesium, copper, potassium, sodium, chloride, fluoride etc); folic acid and vitamins

Aetiology of Micronutrient Deficiencies

  1. Inadequate dietary intake
  2. Increased requirements
  3. Increased loss (e.g. worm infestation)

Epidemiology

Global; high prevalence in under-developed countries, especially sub-Saharan Africa

Clinical features of Micronutrient Deficiencies

  1. Iron: anaemia
  2. Iodine: goitre
  3. Zinc, copper: manifestations of enzyme and
  4. insulin deficiencies
  5. Calcium: rickets, osteomalacia Phosphorus and fluoride: teeth and bone abnormalities
  6. Vitamins:
    1. A: keratomalacia, corneal xerosis, night blindness
    2. B (thiamine): beri-beri
    3. B (riboflavin): scrotal and vulval. dermatoses, angular stomatitis, scars, magenta tongue, cheilosis
    4. B (niacin): scarlet and dry tongue, pellagra 6
    5. Ascorbic acid: scurvy, petechiae and
      musculo-skeletal haemorrhages
    6. D: rickets, epiphyseal enlargement, muscle wasting, bossing of skull bone, ‘thoracic rosary’, persistently open
      anterior fontanelle, genu valgum or varum

Investigations

  • Blood, urine and stool tests.
  • Other investigations as appropriate

Treatment objectives

  • Correct nutrient deficiencies
  • Ensure adequate intake
  • Prevent complications

Treatment for Micronutrient Deficiencies

  • Administration of specific nutrients (as concentrates in foods)
  • Food supplementation
  • Treat underlying diseases

Prevention

  • Nutritional counselling
  • Optimal breastfeeding and appropriate weaning practices
  • Adequate intake of locally available, nutritious foods.
  • Personal/food/water hygiene
    Prophylactic therapies for malaria