Nutritional Deficiencies

Question 1

How does acute and chronic alcohol intake cause malnutrition?

Answer 1

1. Decrease calorie intake
2. Interfere with nutrient digestion and absorption
3. Reduce protein synthesis and secretion
4. Breakdown of gut proteins
5. Increasing excretion of nutrients

Question 2

Causes of malnutrition

Answer 2

Nausea, vomiting
Diarrhea
Poor food availability/quality
Dietary restriction (anorexia, etc.)
Metabolic disturbances (hypermetabolism/catabolism)
Alcoholism
Cytokine effects 
Complications of liver disease

Question 3

Vitamin A (retinol)

Answer 3

Dietary Source: liver,fish,eggs,milk
Carotenoids (yellow and leafy green veggies)

Functions:
Visual pigment
Specialized epithelia
Resistance to infection

Question 4

Vitamin A toxicity

Answer 4

Too much vitamin A
Acute: headache, vomiting, stupor, death
Chronic: weight loss, vomiting, dry lips, bone and joint pain
Congenital malformations: why accutane (synthetic retinoids) are contraindicated during pregnancy

Question 5

Carotenemia

Answer 5

Excessive vitamin A precursors 
Eating too many carrots or leafy veggies
Orange skin (palms and soles)
Sclera remain white
Not associated with toxicity

Question 6

Vitamin D (sources, causes of deficiency, function, signs of deficiency)

Answer 6

Sources:
Endogenous: We make from sunlight
Diet: Most dairy products are fortified

Causes of deficiency:
No calcium or vitamin D
No sunlight (veiled women, northern latitudes)
In children with mothers who have frequent pregnancies (lactation)

Functions: intestinal absorption of calcium and phosphorus and mineralization of bone

Signs/symptoms of deficiency:
Rickets in children (bone has not closed)
Osteomalacia
Weakness of proximal muscles (closest to midline)
Bone pain and tenderness
Hypocalcemia

Question 7

Osteomalacia vs. Rickets

Answer 7

Osteomalacia: epiphyses have closed in adults

Rickets: epiphyses have not closed (bowing)

Epiphyses: end part of the long bone, initially growing separately from the shaft

Question 8

Vitamin C (functions and sources)

Answer 8

Water soluble vitamin
Functions: antioxidant and formation of collagen (important for hydroxylation of procollagen)

Sources: fruits and veggies

Question 9

Scurvy

Answer 9

Disease of vitamin C deficiency

Bone disease in growing children and by hemorrhage and healing defects in children and adults

People at risk: elderly who live alone, alcoholics, infants fed only processed milk

Ex. thin, elderly woman, bad diet; boy who ate only cookies

Question 10

Vitamin C (signs/symptoms)

Answer 10

Weakness, easy fatigue
Aching bones, joints, muscles, esp. at night
Acne
Defects of hairs on body (corkscrew hairs, swan neck deformities)
Easy bruising
Loss of teeth

Question 11

Fat soluble vitamins

Answer 11

Vitamin A, D, E, K

Question 12

Water soluble vitamins

Answer 12

Vitamin B1, B2, B6, B12
Niacin
Vitamin C
Folate
Zinc
Iron

Question 13

Vitamin A (signs/symptoms of deficiency)

Answer 13

Night blindness
Xerosis (eye dryness)
Keratomalacia (loss of functional keratin)
Corneal ulceration and blindness
Perifollicular hyperkeratosis (accumulation at Hyperkeratonized skin around hair follicles, seen on upper arms and thighs)
Squamous metaplasia: benign change of epithelia
Vulnerability to infection

Question 14

Vitamin E

Answer 14

Function:
Major antioxidant
Scavenges free radicals

Deficiency syndromes: spinocerebellar degeneration

Question 15

Vitamin K

Answer 15

Function:
Cofactor in hepatic carboxylation of procoagulants: factors II (prothrombin), VII, IX, X, and protein C and S

Deficiency syndromes:
Bleeding diathesis (too much bleeding)

Question 16

Vitamin B1 (Thiamine)

Answer 16

Function:
Pyrophosphate, coenzyme in decarboxylation reactions

Deficiency:
Dry and wet beriberi
Wernicke syndrome (encephalopathy)
Korsakoff syndrome (psychosis)

Causes mito dysfunction and oxidative toxicity in brain

Brainstem, pons, midbrain occulomotor dysfunction

Cerebellum: ataxia (body movements)

Diancephalon, medial thalamus, amygdala- amnesia and confusion

Question 17

Vitamin B2 (riboflavin)

Answer 17

Source: meat, dairy, veggies

Function:
Converted to coenzymes flavin mononucleotide and flavin adenine dinucleotide, cofactors for many enzymes in intermediary metabolism

Deficiency:
Economically deprived developing countries
Alcoholism, chronic infections, adv. cancer, anorexia, avoid milk

symptoms:
Ariboflavinosis, cheliosis, stomatitis, glossitis, dermatitis, corneal vascularization

Question 18

Niacin (vitamin b3)

Answer 18

Source: grain, legumes, seed oil; unabsorbable in corn; endogenously from tryptophan

Function: Incorporated into NAD and NAD phosphate, involved in redox reactions

Deficiency:
Pellagra: Dementia, dermatitis (bilateral, symmetrical, skin exposed to sun), diarrhea (atrophy of columnar epithelium in GI tract)

Question 19

Vitamin B6 (pyridoxine)

Answer 19

Occurs in over half of alcoholic patients, rare in non-alcoholics

Function:
Derivatives serve as coenzymes in many intermediary reactions

Deficiency: cheilosis (cracks at angle of mouth), glossitis (atrophic tongue), dermatitis, peripheral neuropathy
Maintenance of myelinization of spinal cord tracts

Question 20

Vitamin B12 (cobalamin)
function
deficiency causes
symptoms
eti

Answer 20

Function: Normal folate metabolism and DNA synthesis

Deficiency causes:
Megaloblastic pernicious anemia and degeneration of posterolateral spinal cord tracts

Symptoms:
Areflexia
Neuropathy

Causes: 
Impaired absorption
Gastrectomy (stomach removed)
Ileal resection
Competition from tapeworms
Vegetarianism

Question 21

Folate (B9)
source,
function,
cause,
deficiency causes:

Answer 21

Source: whole wheat, beans, leafy, fortified in flour

Function:
Transfer and use of one-carbon units in DNA synthesis

Cause:
Inadequate intake
malabsorption
increased losses
hemodialysis (kidney failure)

Deficiency:
Megaloblastic anemia (more rapid than b12), neural tube defects (increase requirements in pregnancy)
Acute and chronic glossitis

Question 22

Zinc

Answer 22

Function:
Components of enzymes, principally oxidases

Deficiency: inadequate supplementation in artificial diets
Interference with absorption by other dietary factors
Inborn error of metabolism

Rash around eyes, mouth, anus 
Anorexia and diarrhea
Growth retardation in children
depressed mental function
Depressed wound healing/immune
Impaired night vision
Infertility

Question 23

Iron

Answer 23

Most common nutritional disorder (inadequate hemoglobin synthesis)

Sources: meats, fortified flours and grains

Function
Essential component of hemoglobin as well as metalloenzymes

Deficiency:
Inadequate diet
Chronic blood loss

Hair loss
Pallor
Increasing fatigue
Exertional dyspnea, tachycardia
Pale mucous membranes
Spoon shaped nails (koilonychia)
Hypochromic microcytic anemia

Question 24

Wernicke encepaholapthy

Answer 24

Acute thiamine deficiency

Generally reversible with large doses of thiamine

Confusion, nystagmus (uncontrolled eye movements), opthalmoplegia (paralysis), ataxia, short term memory loss, death

Question 25

Korsakoff Psychosis

Answer 25

Permanent brain damage

Supplementing with thiamine will not affect

Loss of memory for distant events, inability to form new memories, loss of insight, intuition

Demyleination of limbic system

Question 26

Megaloblastic Anemia

Answer 26

Abnormally large RBCs
Impairment of DNA synthesis

2 types: pernicious anemia (major form of B12 deficiency anemia)
Folate deficiency anemia (B9)

Question 27

Body usage of Thiamine

Answer 27

Body has 18 days of thiamine stores

Thiamine is converted to active form in glial and neuronal cells

coenzyme for biochem pathways in brain
glucose metabolism

Enzymes:
A ketoglutarate dehydrogenase
pyruvate dehyrdrogenase
transketolase