Nutrition

Fat-soluble vitamins are vitamins A, D, E, and K.

* Pre-exam preparation for medicine, HN Sarker

Water-soluble vitamins are:

• Thiamin (vitamin B₁)
• Riboflavin (vitamin B₂)
• Niacin (vitamin B₃)
• Pyridoxine (vitamin B₆)
• Biotin (vitamin B₇)
• Vitamin B₁₂ and folate
• Vitamin C (ascorbic acid).

* Pre-exam preparation for medicine, HN Sarker

1. Skin: Vitamin D
2. Intestine (by intestinal flora): Vitamin B₁₂, vitamin K, vitamin B₇

* Kumar and Clark’s Clinical Medicine, 9th Edition Box: 10.13 

Ocular manifestations of xeropthalmia:

• XN – Night blindness
• X1A – Conjunctival xerosis
• X1B – Bitot’s spot
• X2 – Corneal xerosis
• X3A – Corneal ulceration / keratomalacia involving < 1/3 of corneal surface
• X3B – Corneal ulceration/keratomalacia involving ≥ 1/3 of corneal surface
• XS – Corneal scar
• XF – Xerophthalmic fundi (white retinal lesion)

Extra-ocular manifestations:

• Skin chances: Dry scaly skin specially over the outer aspect of the limbs called follicular hyperkeratosis (phrynoderma).
• Susceptibility to infection: Increased.
• Sqamous metaplasia: Involving respiratory, urinary and vaginal epithelium.
• Urinary problem: Renal and vesical calculi, pyuria, haematuria.
• CNS problems: Raised intracranial pressure, rarely optic or cranial nerve palsy, mental retardation, apathy.

* Step on to Paediatrics, Md Abid Hossain Mollah, 3rd Edition Page: 80

All the stages of xerophthalmia should be treated immediately with vitamin A.

Dose recommendation:

* Step on to Paediatrics, Md Abid Hossain Mollah, 3rd Edition Page: 80

Giving oral vitamin A supplement –

1. 100000 IU first day
2. 100000 IU second day
3. 100000 IU eighth day

* Pre-exam preparation for medicine, HN Sarker

The eye lesions are completely reversible at the stage of conjunctival or corneal xerosis, but once keratomalacia develops blindness is inevitable.

Prevention of xerophthalmia / vitamin A deficiency:

• Exclusive breast feeding.
• Routine vitamin A supplementation (every 6 months upto 5 years).
• Vitamin A supplementation in special situations e.g. diarrhoea and measles.
• Regular intake of vitamin A rich foods e.g. dark green, leafy vegetables, coloured fruits, egg, liver, fat of fish, meat, cod liver oil, mola-dhela fish etc.

* Step on to Paediatrics, Md Abid Hossain Mollah, 3rd Edition Page: 80

Acute overdose leads to nausea and headache, increased intracranial pressure and skin desquamation.

* Pre-exam preparation for medicine, HN Sarker

It can cause liver damage, hyperostosis, and teratogenicity.

* Pre-exam preparation for medicine, HN Sarker

Deficiency features are:

Beriberi—

1. Dry (or neurological) beriberi—manifests with chronic peripheral neuropathy and with wrist and/or foot drop and may cause Korsakoff’s psychosis and Wernicke’s encephalopathy.
2. Wet (or cardiac) beriberi—Generalized edema due to biventricular heart failure with pulmonary congestion.

* Davidson’s Principles and Practice of Medicine, 22nd edition Page: 128; Pre-exam preparation for medicine, HN Sarker

Pellagra (the disease of the three Ds)— Dermatitis, diarrhea, and dementia.

* Pre-exam preparation for medicine, HN Sarker

The haematological disorders –

• Macrocytic or megaloblastic anaemias.

Neurological findings in B₁₂ deficiency –

1. Peripheral nerves
   • Glove and stocking paraesthesiae
   • Loss of ankle reflexes
2. Spinal cord
   • Subacute combined degeneration of the cord
     • Posterior columns – diminished vibration sensation and proprioception
     • Corticospinal tracts – upper motor neuron signs
3. Cerebrum
   • Dementia
   • Optic atrophy
4. Autonomic neuropathy

Davidson’s Principles and Practice of Medicine, 22nd edition Page: 129, 1024

Folic acid deficiency is more common. Because –

1. Folic acid is more destroyed by heating (60-90%) during cooking.
2. Requirement of folic acid is more.
3. Vitamin B₁₂ is less destroyed (10-30%) by heating during cooking.
4. Daily requirement of vit-B₁₂ is less (only 3 μg).
5. Vit-B₁₂ can be stored in liver for long time (3 years).

Scurvy is the deficiency features of vitamin C deficiency.

* Pre-exam preparation for medicine, HN Sarker

Pathogenesis –
Vitamin C is essential for hydroxylation of lysine and proline for the formation of collagen. Its deficiency leads to faulty collagen tissue synthesis in bones, cartilage and teeth. In addition, the intercellular substance of capillaries also become defective often leading to bleeding.

* Step on to Paediatrics, Md Abid Hossain Mollah, 3rd Edition Page: 80

Clinical features are—

1. Swollen gums which bleed easily
2. Petechial and perifollicular hemorrhages giving rise to corkscrew hair
3. Ecchymosis
4. Hemarthrosis
5. Gastrointestinal bleeding
6. Anemia
7. Poor wound healing.

* Davidson’s Principles and Practice of Medicine, 22nd edition Page: 130; Pre-exam preparation for medicine, HN Sarker

Clinical manifestations: 

Peak incidence is around 6-24 months of age. Presenting symptoms include-

• Vague irritability and loss of appetite.
• The baby cries on handling e. g. dressing, bathing etc.
• Generalized tenderness especially in legs resulting in pseudo-paralysis and legs assume typical frog position.
• Bluish purple, spongy swelling of gum mucosa is seen when tmth are erupted.
• Sharp painful scorbutic rosary is palpable at costochondral junction and depression of sternum.
• Peri-follicular haemorrhage, petechial haemorrhage, ecchymosis of extremities, haematuria, melaena, orbital haemorrhage may be found.
• Delay in wound healing.

* Step on to Paediatrics, Md Abid Hossain Mollah, 3rd Edition Page: 80

X-findings are:

1. Epiphysis is ring-shaped, sclerotic and sharply demarcated (Wimberger’s sign).
2. Metaphysis is dense resembling a white line (white line of Frankle).
3. Beneath metaphysic, a lucent zone (Trumerfeld zone) is present.
4. There is spur at the corner (Pelkan’s spur).

* Pre-exam preparation for medicine, HN Sarker

• For rapid recovery oral Vit C 200 mg daily for several weeks. The administration of 3-4 ounces of tomato or orangejuice are equally effective.
  • Clinical recovery occurs within 24-48 hours.
  • Radiological improvement takes a week or two; disappearance of sub-periosteal haemonhage takes months.
• After scurvy has been cured, 35-50 mg of  vitamin C should be given daily as drug or in diet.
• Dietary supplements especially fresh fruits (orange, mango, pineapple, guava, etc.) and liver extract.
• Bottle-fed infants should be given fruit juice. Nursing mother should take sufficient vitamin C, which is secreted in the breast milk.

* Step on to Paediatrics, Md Abid Hossain Mollah, 3rd Edition Page: 81; Short Cases in Clinical Medicine, ABM Abdullah Page: 563

Deficiency features of vitamin D are:

– In children—Rickets

– In adult—Osteomalacia.

* Pre-exam preparation for medicine, HN Sarker

The main source of vitamin D in the body is synthesis of cholecalciferol from 7-dehydrocholesterol in the skin by the action of ultraviolet sunlight, a minor portion comes from diet. Cholecalciferol is inactive, which is converted first in the liver to 25-hydroxycholecalciferol (25(OH)D₃) and subsequently in the kidney (by the enzyme 1 hydroxylase) to 1,25-dihydroxycholecalciferol (1,25(OH)₂D₃) which is active form of vitamin D.

* Pre-exam preparation for medicine, HN Sarker

Functions of vitamin D on—

• Intestine—Vitamin D increases Ca²⁺ absorption from the gut.
• Bone—Vitamin D increases calcification of osteoid tissue and also bone resorption.
• Kidney—Vitamin D increases calcium reabsorption and phosphate excretion.

* Pre-exam preparation for medicine, HN Sarker

Rickets is a disease of growing bone which occurs in children before fusion of epiphysis and is due to
inadequate mineralization of growing bones leading to an excess of unmineralized matrix at the growing plate.

* Step on to Paediatrics, Md Abid Hossain Mollah, 3rd Edition Page: 81

1. General features
   • Short stature, listlessness, protruded abdomen, nutscle weakness.
2. Head
   • Box-like square head, hot-cross-bun appeafance of skull, craniotabes.
3. Teeth
   • Delayed dentition, dental caries and impaired enamel formation.
4. Chest
   • Pigeon chest deformity, painless rachitic rosary at costochondral junction, Harrison sulcus.
5. Spine
   • Deformities like scoliosis, kyphosis lordosis etc. These may lead to recurrent respiratory infections.
6. Extremities
   • Widening of wrist and ankle, vulgus and varus detbrmity, amerior bowing of leg, coxa vara, fractures and pain, gait deformity
7. Symptoms of ypercalcaemiah
   • Tetany, seizure, stridor due to laryngeal spasm.

* Step on to Paediatrics, Md Abid Hossain Mollah, 3rd Edition Page: 82

1. X-ray upper and lower limbs including knee, ankle, elbows and wrist joints.
2. Serum calcium and phosphate (both are low).
3. Serum alkaline phosphatase (high).
4. Seium 25-hydroxy proline (low or absent).

* Short Cases in Clinical Medicine, ABM Abdullah Page: 562; Step on to Paediatrics, Md Abid Hossain Mollah, 3rd Edition Page: 84

1. X-ray knee & wrist shows:
   • Widening, splaying, cupping, and irregularities of metaphysis
   • Distance between epiphysis and metaphysis is increased (zone of provisional calcification is lost)
   • Density of shaft of bone is reduced (ostmpenia)
   • Deformity of long bone may be present
   • Green stick fracture may be present
2. Chest X-ray shows:
   • Chondral ends of ribs are expanded, cupped and indistinct
   • Rachitic rosary may be identified radiologically.

* Pre-exam preparation for medicine, HN Sarker; Short Cases in Clinical Medicine, ABM Abdullah Page: 562; Step on to Paediatrics, Md Abid Hossain Mollah, 3rd Edition Page: 84

• 25-Hydroxycholecalciferol, 50 µg daily or active vitamin D metabolite ( 1-α-hydroxycholecalciferol ), 1- 2 µg daily or 1,25 di-hydroxycholecalciferol, 0.25 to 1.5 µg daily.
• Plus calcium-500-1000 mg daily. Higher dose may be required in patients with malabsorption.
• Adequate exposure to sunlight.
• Dietary supplement.

* Short Cases in Clinical Medicine, ABM Abdullah Page: 562

Common nutritional disorders are:

• Kwashiorkor
• Marasmus
• Iodine deficiency
• Night blindness due to vitamin A deficiency
• Iron deficiency anemia.

* Pre-exam preparation for medicine, HN Sarker

* Pre-exam preparation for medicine, HN Sarker

1. Abnormal micronutrient status is commonly manifest in clinical signs in the skin and mucous membranes, or in other systems.
2. Anthropometric measurements
   • Body mass index (BMI)
   • Waist circumference (measured at the level of the umbilicus)
   • Hip circumference (measured at the level of the greater trochanters)
   • Waist : hip ratios (show whether the distribution of fat is android or gynoid)
   • Skinfold measurements (can be used to calculate body fat content)
   • Mid-arm circumference (at the middle of the humerus) (muscle mass is estimated by subtracting triceps skinfold thickness from mid-arm circumference)
3. Measurement of body fat by bio-impedance or dual energy X-ray absorptiometry (DEXA) scanning.

* Davidson’s Principles and Practice of Medicine, 22nd edition Page: 114