Malnutrition Flashcards
What does cholesterol form?
Steroids hormones
What are the 2 roles of vitamins?
> cofactors involved in enzymatic reactions
(water soluble vitamins ONLY)
> antioxidants
What is a syndrome?
a collection of symptoms that forms a distinct clinical condition
What are the 4 examples of protein energy malnutrition?
Kwashior Kor
Cachexia
Phthitis
Marasmus
What is the cause of Kwashior Kor?
Lack of protein in diet
What are the symptoms of Kwashior Kor?
Oedema Diarrhoea Potbelly Changes in hair + nails Desquamating skin rash Decrease in linear growth
What is oedema?
Excessive accumulation of fluid in tissues
What are the 2 types of oedema?
Which type of oedema occurs in Kwashior Kor?
> Pitting = press down, remove + v slowly springs back to original shape
Non-pitting
Pitting
What are the 2 ‘areas’ oedema can occur?
Local
- e.g. after injury/inflammation
General
- more serious (can have heart/kidney failure)
In which parts of the body can general oedema occur?
What are the names for these conditions?
> within chest cavity
= ‘plural oedema’
> abdomen
= ‘ascites’
> within alveoli
= ‘pulmonary oedema’
What causes oedema?
Decrease in albumin
Where is albumin produced?
What are its 2 roles?
Liver
from amino acids
Act as a carrier
Maintains colloid osmotic pressure
–> exerts attractive force that helps to keep water in blood
How does a decrease in albumin lead to oedema in Kwashior Kor?
Reduction in protein intake -> decreased amino acids -> decrease in albumin produced -> lower attractive force on water in blood = water moves into interstitial space
Define diarrhoea
Bowel movements of increased frequency, volume + liquidity
What are the 3 types diarrhoea?
Which type of diarrhoea is involved in Kwashior Kor?
Osmotic
Malabsorptive
Secretory
Malabsorptive
What is osmotic diarrhoea?
What can this be induced by?
When water is drawn out of cells into the lumen of the intestine
Chemicals
e.g. sorbitol in sugar-free sweets
What is malabsorptive diarrhoea?
Reduced ability to digest/absorb nutrients
due to reduction in digestive enzymes (pancreas) + reduction in absorption (intestine)
- > partially digested food enters the large intestine
- -> stimulates diarrhoea
How long do cells at the tip of villi in the small intestine live for?
How are they replaced?
2-3 days
By stem cells differentiating
Through which 2 ‘mechanisms’ does partially digested food enter the large intestine?
Intestine
Pancreas
What are the 6 types of cells in the small intestine?
Goblet cells Enterocytes Pit cells Stem cells Enteroendocrine cells Paneth cells
What do goblet cells do?
Secrete mucus:
> protects epithelium from stomach acid
> lubricates food
What do paneth cells do?
Produce bactericidal lysozyme
What do enterocytes do?
Absorptive
located at ends of villi
What do enteroendocrine cells do?
Secrete hormones
–> Metabolic affects
What do pit cells do?
Secrete prostaglandins
What do stem cells do?
Replace the other cell types
What role does the intestine play in malaborsptive diarrhoea?
Insufficient amino acid uptake
–> reduction in SA
–> reduction in nutrient absorption
= partially digested food in large intestine
What are the 2 functions of the pancreas?
Endocrine
Exocrine
What is the endocrine function of the pancreas?
Produces hormones: > insulin (by beta cells) > glucagon (alpha) > somatostatin (delta) > pancreatic polypeptide (PP) > ghrelin (episilon)
What are the exocrine functions of the pancreas?
Acinal cells
- produce digestive enzymes e.g. amylase + lipase
- -> secreted into ducts
Ductal cells
- transport to intestine
What role does the pancreas play in malaborptive diarrhoea?
Reduced amino acid intake
–> can’t produce digestive enzymes in pancreas
–> reduces ability to digested food
= partially digested food in large intestine
What causes potbelly?
Hepatomegaly
= enlarged liver
What changes occur in hair in Kwashior Kor?
Alternating bands of poor (light) + good (dark) growth
What changes occur in nails in Kwashior Kor?
Finger clubbing
= nail bed thickens
What happens if you have a desquamating skin rash?
Outer layers of epidermis sloughs off
What causes a desquamating skin rash?
Reduction in proteins that help keep strata together
What are the 6 layers of epidermis?
What is the dermis made up of?
Strata corneum " leucidum " granulosum " spinosum " basale
Fibroelastic tissue
What is Cachexia?
Extreme weight loss/low body weight associated w/ cancer, AIDS + TB
What causes cachexia in cancer patients?
Hyper-catabolism of proteins + lipids in healthy cells by cytokines to supply cancerous cells
–> converted into energy
What are cytokines?
Hormone-like substances that act in a paracrine fashion to mediate immune response
What are the 3 categories of cell signalling?
Endocrine
Autocrine
Paracrine
What does the endocrine system do?
Secretes hormones into blood
- has effect far away from cell where it’s produced
What does the autocrine system do?
Produces substances that have an effect on themselves
What does the paracrine system do?
Has an effect on a neighbouring cell
What are the 2 groups of cytokines?
Give examples.
Inflammatory cytokines:
- Tumour necrosis factor alpha
- TNF2
- Interleukin 6
Tumour-derived catabolic factor
- Proteolysis inducing factor
What effect do Proteolysis inducing factors (PIF) have?
How does death normally occur?
Initiate protein breakdown via proteasome pathway
(Ubiquitin is bound to the protein = ticketing it for degradation)
Through erosion of respiratory muscles
What are the chemical constituents of carbohydrates?
CH2O
What are the chemical constituents of fats?
C, H + O
What are the chemical constituents of proteins?
C, H, O, N, P + S
What is are the functions of fats?
> Provide heat + energy
Transport fat-soluble vitamins
Necessary for nerve sheath + formation of bile
What are the 2 groups of amino acids?
Essential
- derived from diet
Non-essential
- produced by body
What are the functions of proteins?
Provide amino acids for:
>Formation of cells, growth + repair
>Synthesis of hormones
>Synthesis of plasma proteins
What are the functions of water?
> regulation of body temp
major component of blood tissue fluid
formation of urine + faeces
What are the functions of roughage?
> adds bulk to diet
> stimulates peristalsis + bowel movements
What are the 2 types of vitamins?
Group the vitamins
Water soluble :
B1, B2, B6, B12, C, nicotinic acid, pantothenic acid, floats, biotin + choline
Fat soluble:
A, D, E + K
What are the 2 types of malnutrition?
Food deprivation
e.g. protein energy malnutrition
Psychiatric
e. g. anorexia nervosa
e. g. elderly - isolation or dementia
What is phthisis?
Any disease resulting in wastage of tissue
What is marasmus?
Severe wasting in infants
