Overview of micronutrient

deficiency disorders and

clinical signs

By: Darayus P.Gazder

All micronutrients are important for:

1) Growth,

2) Health,

3) Development.

BACKGROUND

Vitamins are organic substances thatare essential for several enzymaticfunctions in human metabolism

A compound is called vitamin when itcannot be synthesized in sufficientquantities by an organism, and must beobtained from the diet.

Functions

Acts as hormones (vitamin D)

Acts as antioxidant (vitamin E)

Acts as mediators of cell signallingand regulators of cell and tissuegrowth and differentiation(vitaminA)

Acts as precusors for enzymecofactor biomolecules(coenzymes)that help act as catalysts andsubstrates in metabolism

VITAMINS

Vitamins are classified accordingto solubility into fat soluble & watersoluble.

13 vitamins are known, 4 fatsoluble (KEDA) & 9 water soluble(C, Folate & the B group).

VITAMINS

Water soluble-dissolve easily inwater readily excreted from the body.

Fat soluble-absorbed through theintestinal tract with the help oflipids(fats).

VITAMIN A-Vitamin A is a

generic term for many related compounds.

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.

FUNCTIONS•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

Animal Foods Plant Foods

Cod liver oil Sweet potato

Liver & kidney Carrots

Egg Spinach

Butter

Milk & cheese

RICH DIETARY SOURCES

Vitamin A deficiency

•Deficiency of vitamin A leads to:

1. Ocular change- Night blindness &

xerophthalmia

2. Extra ocular changes

Growth retardation

Acquired immune deficiency

Anemia

WHO CLASSIFICATION OF

XEROPTHALMIA

PRIMARY SIGNS SECONDARY SIGNS

X1A: Conjunctival

xerosis

X1B: Bitot’s spot

X2: Corneal xerosis

X3A: Corneal ulceration

X3 B: Keratomalacia

XN: Night blindness

XF: Fundal changes

XS: Corneal scarring

Xeropthalmia

Bitots spots (X1B) are foamy white areas on the white of the eye.

Corneal Xerosis(X2) Keratomalacia (X3)

INVESTIGATIONS:

Clinical evaluation(Skin, Eyes, Growth)

Serum retinol <20 mcg/dL;

Molar ratio of retinol:RBP(Retinol

binding protein) <0.7 is also diagnostic

Treatment

• 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

•Hepatosplenomegaly

•Fatigue, malaise, anorexia, vomiting

•Bone pain & increased risk of fracture

•Pseudotumor Cerebri

•Xray-hyperostosis of the shafts of long bones

VITAMIN D

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.

Cholesterol is converted to 7-dehydro-

cholesterol (7DC), which is a precursor of

vitamin D3.

FUNCTIONS

•Calcium metabolism: vitamin D enhances Calcium absorption in the gut & renal tubules.

•Cell differentiation: particularly of collagen & skin epithelium

•Immunity: important for Cell Mediated Immunity & coordination of the immune response.

Sources of Vitamin D

Sunlight is the most important

source

Fish liver oil

Fish & sea food (herring & salmon)

Eggs

Plants do not contain vitamin D3

Human milk deficient in vit. D,

contains only 30-40 IU per liter mostly

from 25(OH)D3

Vitamin D deficiency

•Deficiency of vitamin D leads to:

Rickets in small children.

Osteomalacia

RICKETSLack of adequate mineralisation of growing bone

CLINICAL FEATURES

RICKETS

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 problems.

INVESTIGATIONS

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.

Metaphyseal

cupping and

fraying in the

distal radius

and ulna in

rickets

TREATMENT

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

milk

Rickets: 1600-5000IU of VitD3 per day

Stross therapy:

TOXICITY•Hypervitaminosis D – infants-2,000-3,000 IU/day,

adults-10,000 IU/day for several months.

causes hypercalcemia,hyperphosphatemia,

hypertension which manifest as:

Nausea & vomiting

Excessive thirst & polyuria

Severe itching

Joint & muscle pains

Azotemia, nephrolithiasis, ectopic calcification.

Disorientation & coma.

Vitamin K

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 disease

Promotes healing of wounds, fractures and bruises

Sources

Citrus fruits, strawberries, kiwifruit, blackcurrants, papaya, and vegetables

Scurvy – Signs & Symptoms

Small blood vessels fragile

Gums reddened and bleed easily

Teeth loose

Joint pains

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

children

Legs assume a “frog like position”(Hips and knees

are semiflexed with the feet rotated outwards)

Diagnosis

History+Clinical Features

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

Treatment

Prevented by a diet of Vitamin C

Daily therapeutic dose of Vitamin C is 100-200mg

or more.

Daily requirement is 45-60mg/day in children

Thiamin – Vitamin B1

What it does in the body

energy production and carbohydrate and fatty

acid metabolism

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

muscles

Wet Beriberi cardiopathy

Edema of legs, trunk and face

Congestive heart failure (cause of death)

Wrist & foot drop:

Dry Beri Beri

Edema:

Wet Beri Beri

Riboflavin Deficiency

Deficiency is rare and often occurs with other

B vitamin deficiencies

Several months for symptoms to occur

Burning, itching of eyes

Angular stomatitis

Cheilosis

Swelling and shallow ulcerations of lips

Glossitis

Riboflavin deficiency

Angular stomatitis Glossitis

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

vitamin

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 brown pigmentation

dementia, tremors, irritability, anxiety, confusion and depression

Pellagra Dermatitis

Anemia

Iron deficiency is the most common cause of anemia and

most common preventable nutritional deficiency.

Causes:Nutritional

Mother anemic

Increased Fe

demands:(Preterm,IUGR,

Cyanotic heart disease)

Prolonged breastfeeding,

cow milk

Malabsorption

Poor weaning

Blood Loss

1. Neonates:

Fetomaternal transfusions

Twin to twin transfusions

Bleeding from umblical cord

Hemorrhagic disease of

Newborn

2. Children:

Hookworm infestation

Rectal polys

IBD

Anemia- Signs & Symptoms Symptoms

Tiredness/ Fatigue/ Headache/Breathlessness

Signs

Pallor: Pale conjunctivae, palms, tongue, lips, skin,

Spoon shaped nails.

Tachycardia, Systolic murmur

If Hb<3, check for

signs of CHF

Investigations:

CBC: 1) Hemoglobin <11.0 g/dL

MVC/ MCH/ MCHC are all decreased

Reticulocyte count: Normal or minimally elevated

Peripheral blood smear:

Microcytic hypochromic anemia

Serum Fe levels: Decreased

TIBC: Increased

Serum ferritin levels: Decreased

Normal Blood Film

MICROCYTES

HYPOCHROMIA

Anemia- Treatment

Dietary counseling: Infants fortified milk formula less than 1yr

of age

Dietary diversification

Foods that are rich in iron include:

Meat/ Fortified cereals/ Spinach/Lentils and beans

Iron supplements

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 Deficiency

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

weaning

Zinc interventions are among those proposed to

help reduce child deaths globally by 63% (Lancet,

2003)

Zinc Deficiency- Signs & Symptoms

Skin lesions

Immune impairment

Diarrhea

Poor growth

Acrodermatitis enteropathica:

AR disorder (defect of Zn absorption)

Begins within 2-4 weeks of

weaning

Perioral/ Perianal dermatitis/

Failure to thrive

Zinc Deficiency- Assessment

No simple, quantitative biochemical test of zinc status

Serum Zinc• Can fluctuate as much as 20% in 24-hour period

• Levels decreased during acute infections

• Expensive

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