Overview of micronutrient
deficiency disorders and
By: Darayus P.Gazder
All micronutrients are important for:
Vitamins are organic substances that
are essential for several enzymatic
functions in human metabolism
A compound is called vitamin when it
cannot be synthesized in sufficient
quantities by an organism, and must be
obtained from the diet.
Acts as hormones (vitamin D)
Acts as antioxidant (vitamin E)
Acts as mediators of cell signalling
and regulators of cell and tissue
growth and differentiation(vitamin
Acts as precusors for enzyme
that help act as catalysts and
substrates in metabolism
Vitamins are classified according
to solubility into fat soluble & water
13 vitamins are known, 4 fat
soluble (KEDA) & 9 water soluble
(C, Folate & the B group).
Water soluble-dissolve easily in
water readily excreted from the body.
Fat soluble-absorbed through the
intestinal tract with the help of
VITAMIN A-Vitamin A is a
generic term for many related
Retinol (alcohol), Retinal (aldehyde)
are often called preformed vitamin A.
Retinal can be converted
by the body to retinoic
acid which is known to
affect gene transcription.
Body can convert b-carotene
to retinol, thus called provitamin A.
•Immunity: important for activation of T
lymphocyte, maturation of WBC & integrity
of physiological barrier.
•Vision: integrity of eye & formation of
rodopsin necessary for dark adaptation.
•Red blood cell production
•Regulation of gene expression: vital to
cell differentiation & physiologic processes
• Growth & development
Bitots spots (X1B) are foamy white areas on the white of the eye.
Corneal Xerosis(X2) Keratomalacia (X3)
Clinical evaluation(Skin, Eyes, Growth)
Serum retinol <20 mcg/dL;
Molar ratio of retinol:RBP(Retinol
binding protein) <0.7 is also diagnostic
• Overall mortality is reduced by 23%
• Death from measles is reduced by 50%
• Death from diarrhea is reduced by 40%
TOXICITY- Children and adults ingesting
>50,000 IU/day for several month.
•Vitamin A in excess leads to:
•Dermatitis with xanthosis cutis
•Fatigue, malaise, anorexia, vomiting
•Bone pain & increased risk of fracture
•Xray-hyperostosis of the shafts of long
Vitamin D comprises a group of sterols; the
most important of which are cholecalciferol
(vitamin D3) & ergosterol (vitamin D2).
Humans & animal utilize only vitamin D3 &
they can produce it inside their bodies from
Cholesterol is converted to 7-dehydro-
cholesterol (7DC), which is a precursor of
•Calcium metabolism: vitamin D enhances
Calcium absorption in the gut & renal
•Cell differentiation: particularly of
collagen & skin epithelium
•Immunity: important for Cell Mediated
Immunity & coordination of the immune
Sources of Vitamin D
Sunlight is the most important
Fish liver oil
Fish & sea food (herring & salmon)
Plants do not contain vitamin D3
Human milk deficient in vit. D,
contains only 30-40 IU per liter mostly
Vitamin D deficiency
•Deficiency of vitamin D leads to:
Rickets in small children.
Lack of adequate mineralisation of growing bone
Sign and symptoms-
•Skeletal deformity-bowed legs(genu varum) in toddlers,
knock knees (genu valgum) in older children,
craniotabes (soft skull), spinal and pelvic deformities,
growth disturbances, costochondral swelling(rickety
rosary), harrisons groove, greenstick fractures, bone
pain and tenderness, muscle weakness and dental
Radiologic changes-loss of normal zone of provisional
calcification adjacent to metaphysis.
Widening of the growth plate.
Splaying and cupping of metaphysis.
Generalized reduction in bone density.
Low circulating levels of 25(OH)D3.
Elevated serum alkaline phosphate.
Calcium level may be normal or low
Phosphate level usually are unchanged or low.
fraying in the
and ulna in
AAP: 400IU/day for all breastfed infants, beginning in
1st 2months of life and continue until infant is receiving
>500ml/day of vitamin of formula or vitamin D fortified
Rickets: 1600-5000IU of VitD3 per day
•Hypervitaminosis D – infants-2,000-3,000 IU/day,
adults-10,000 IU/day for several months.
hypertension which manifest as:
Nausea & vomiting
Excessive thirst & polyuria
Joint & muscle pains
Azotemia, nephrolithiasis, ectopic calcification.
Disorientation & coma.
It is a cofactor of the enzyme that catalyzes one
step in the formation of prothrombin.
Needed for the generation of several clotting
factors in the liver.
Source- green leafy vegetables.
Deficiency-coagulation defect due to
hypoprothrombinemia and deficiency of factor VII
resulting in hemorrhagic disease of the newborn.
1mg IM –newborn.
In severe deficiency-2.5 to 5 mg/day parenterally.
Vitamin C - Ascorbic Acid
Humans are among the few species that
cannot synthesize vitamin C and must obtain
it from food
Manufacture of collagen
Helps support and protect blood vessels,
bones, joints, organs and muscles
Protective barrier against infection and
Promotes healing of wounds, fractures and
Citrus fruits, strawberries, kiwifruit,
blackcurrants, papaya, and vegetables
Scurvy – Signs & Symptoms
Small blood vessels fragile
Gums reddened and bleed easily
Scorbutic rosary: Costochondral junction is more angular
and has a sharper step-off
Dry scaly skin
Lower wound-healing, increased susceptibility to
infections, and defects in bone development in
Legs assume a “frog like position”(Hips and knees
are semiflexed with the feet rotated outwards)
Xray appearance of long bones:
1. Ground glass appearance of bones
2. Cortex is reduced to “Pencil Point” thinness
3. There is white line of Fraenkel (An irregular but
thickened white line at metaphysis representing
the zone of well calcified cartilage
Low levels of Vitamin C
Prevented by a diet of Vitamin C
Daily therapeutic dose of Vitamin C is 100-200mg
Daily requirement is 45-60mg/day in children
Thiamin – Vitamin B1
What it does in the body
energy production and carbohydrate and fatty
vital for normal development, growth,
reproduction, healthy skin and hair, blood
production and immune function
Deficiency due to diets of polished rice
Beri Beri- Signs & Symptoms
Develop within 12 weeks
Dry Beriberi peripheral neuropathy
Difficulty walking and paralysis of the legs
Reduced knee jerk and other tendon reflexes, foot
and wrist drop
Progressive, severe weakness and wasting of
Wet Beriberi cardiopathy
Edema of legs, trunk and face
Congestive heart failure (cause of death)
Wrist & foot drop:
Dry Beri Beri
Wet Beri Beri
Deficiency is rare and often occurs with other
B vitamin deficiencies
Several months for symptoms to occur
Burning, itching of eyes
Swelling and shallow ulcerations of lips
Niacin – Vitamin B3
Essential for healthy skin, tongue, digestive
tract tissues, and RBC formation
Processing of grains removes most of their
niacin content so flour is enriched with the
Pellagra – Signs & Symptoms
‘Three Ds’: diarrhea, dermatitis and dementia
Reddish skin rash on the face, hands and
feet which becomes rough and dark when
exposed to sunlight (pellagrous dermatosis)
acute: red, swollen with itching, cracking,
burning, and exudate
chronic: dry, rough, thickened and scaly with
dementia, tremors, irritability, anxiety,
confusion and depression
Dietary counseling: Infants fortified milk formula less than 1yr
Foods that are rich in iron include:
Meat/ Fortified cereals/ Spinach/Lentils and beans
Mild to moderate anemia: 3-6mg/kg/day of iron (3-5 months)
Severe anemia and cardiac decompensation: Start blood
transfusions, packed RBC’s: (2-3ml/kg)
Zinc essential for the function of many enzymes
and metabolic processes
Zinc deficiency is common in developing countries
with high mortality
Zinc commonly the most deficient nutrient in
complementary food mixtures fed to infants during
Zinc interventions are among those proposed to
help reduce child deaths globally by 63% (Lancet,
Zinc Deficiency- Signs & Symptoms
AR disorder (defect of Zn absorption)
Begins within 2-4 weeks of
Perioral/ Perianal dermatitis/
Failure to thrive
Zinc Deficiency- Assessment
No simple, quantitative biochemical test of zinc status
• Can fluctuate as much as 20% in 24-hour period
• Levels decreased during acute infections
Hair zinc analysis
Zinc Deficiency- Treatment
Regular zinc supplements can greatly reduce common
infant morbidities in developing countries
• Adjunct treatment of diarrhea
-10 mg/day for infants below 6 months,
-20mg/day of zinc for 10-14 days(>6months)
Zinc deficiency commonly coexists with other
micronutrient deficiencies including iron, making
single supplements inappropriate
Emperical trial of Zinc supplementation(1ug/kg/day)
is safe and reasonable