Random Physio / Biochem

Question 1

1. presentation of CF pts
2. How to test for CF

Answer 1

1. Heat stroke + salt depletion
   High (>60mM) [Na+] in sweat (normal <40mM)
2. Pilocarpine (M3 ag); iontophoresis stimulation test

Question 2

Cystic Fibrosis Gene:

1. Affected organs
2. End-stage presentation of CF pt
3. Mutation
4. Protein polarization

Answer 2

1. Pancreas, sweat gland, lung, intestine, repro tract, heart, kidney
2. Lung = end-stage. If they survive this, end-stage = kidney + LVH (??)
3. Deletion of ΔF508 (phenylalanine) @ BOTH alleles
4. ATP-binding Cassette (ABC) that is ALWAYS on apical membranes of epithelium

Question 3

Cystic Fibrosis protein rating

Answer 3

Rated between Class I-VI

I - NO protein (worst)
VI - accelerated turnover (best)

Protein functions via PKC & PKA

Question 4

Cystic Fibrosis protein:

normal vs mutated

Answer 4

@ sweat gland

Normal: CFTR functions to generate potential difference & keep it @ constant

If CFTR is non-fx –> NO Cl- driving force –> K+ hyperpolarizes cell, decreased Na+, Cl- absorbed
–> increased Na & Cl in sweat (hypertonic)

Question 5

Major effects of CF

Answer 5

1. Mucus blocks airway -> bronchiectasis, infx, pneumonia
2. Steatorrhea, decr. fat soluble vits / protein / carbs
3. Fluid hyperabsorption -> meconium ileus
   ***FIRST SIGN

Question 6

Pharmacotherapy of Cystic Fibrosis

Answer 6

Airways made to prevent uptake of foreign material

Mucolytics
Anticholinergics
DNAse
B-adrenergics
Aerosolized Saline (Hypertonic)

TOC: Percussion

Question 7

MUTYH (mutY-homolog)/MAP

• Inheritance pattern
• Clinical signs

Answer 7

• Autosomal RECESSIVE
• 10+ polyps

Question 8

What is the most sensitive diagnostic method of Lynch Syndrome?

Answer 8

Microsatellite instability + followup tests
will show extra microsatellite bands due to mismatch repair deficiency

(Criteria are specific, but lots of false negatives)

Question 9

What is the Amsterdam-II criteria for Lynch Syndrome?

Answer 9

3-2-1: all at same time

3+ relatives w/Lynch-type cancers

2 generations

1 diagnosed before 50y

Question 10

What are the first and second hits of Mismatch repair mutation?

What disease is associated with this mutation type?

Answer 10

Lynch Syndrome (HNPCC)

1. First hit: Inherited mutation (MSH2, MLH1)
2. Independent mutation / LOH / Methylation & inactivation of promotor

Question 11

What are the diagnostic clues of Lynch Syndrome?

Answer 11

1. Young age
2. Family hx with CRC
3. 7-10% have more than 1 tumor at initial diagnosis (sporadic CRC is highly unlikely to have +1)
4. Different histology

**can also cause endometrial or other cancers

Question 12

What is Loss of Heterozygosity?

Answer 12

A region of chromosome that only has faulty allele, thus looks homozygous.

Cells in tumor show LOH

Only with tumor suppressor gene mutations (frequent for inherited, but can also be seen with somatic)

Question 13

Familial Adenomatous Polyposis (FAP)

1. Clinical signs
2. Genetics

Answer 13

1. >100 polyps
   Fe-defx Anemia
   Avg age 45y
2. AD mutation of APC tumor suppressor gene
   De novo inheritance in 1/4 cases
   Somatic mutation has fewer polyps

Question 14

What are clinical signs of APC gene mutation carriers?

Answer 14

• Polyps in upper GI, duodenum
• Congenital Hypertrophy of Retinal Pigment Epithelium (CHRPE)
• • multiple patches are pretty specific for APC mutation
• Extra-intestinal cancers

Question 15

What type of genes do inherited cancers affect?

Answer 15

Tumor Suppressor genes

Question 16

Familiar cancers– more likely to be sporadic or inherited?

Answer 16

Sporadic… but has been proven to have genetic predisposition

Question 17

Mild hepatitis:

S/S

Dietary management

Answer 17

S/S: ill-looking, loss of appetite

Diet: light, high in proteint, do NOT RESTRICT FAT (reccomment milk, butter, cheese)

Question 18

Chronic active hepatitis

S/S

Dietary management

Answer 18

• Exhaustion, fluctuating jaundice
• Ascites (later stages)

For ascites: bed rest + low-sodium diet with fluid restriction

Question 19

Alcoholic Hepatitis: dietary management

Answer 19

High protein and energy

Multivitamin with Thiamine + folate

Question 20

Cholecystitis:

S/S

Dietary management

Answer 20

S/S: jaundice, RUQ pain, N/V, flatulence

Initial Diet: NIL by mouth

Later: Low fat diet (20-25% daily total cals = 40-55g)
very low fat diet contraindicated (eggs are good?!)

Question 21

Hepato-renal Failure: dietary management

Answer 21

Sodium & Protein restriction

Question 22

Biliary Cirrhosis:

Dietary management

Answer 22

Low fat diet

Medium-chain triglyceride supplement

Question 23

When is a low fat diet advised?

When is a low protein diet avised?

Answer 23

Low fat: biliary cirrhosis

Low protein: Hepato-renal failure

Question 24

Pre-op Bariatric Surgery diet

Answer 24

• Clear liquids
• General calorie reduction (Try to lose 10% excess weight w/in 1 mo before surgery)
• 1.0 - 1.5 g/kg protein
• 1/4 sugar free, non-carbonated water every 15min (not during meals)
• 100-200% DV vitamins, Calcium citrate & vit D, B12 & iron
  
  • In highly malabsorptive surgery- fat soluble vit.

Question 25

Post-op Bariatric Surgery Diet

Answer 25

Avoid Nuts, seeds, popcorn, dried fruit, granola, fibrous veg, candy, ice-cream, tough meat/gristle * Phase 1: liquid diet * Phase 2 (2-4w): pureed food (lean ground meat, beans, egg whites, yogurt, sodas, veg, cottage cheese) * Phase 3 (4-8w): soft solid foods (ground meat, canned/cooked veg, fruit) * Phase 4 (8w+): small amounts of regular food, 64oz fluid/day (don't use straws) \*\*always monitor for **fat loss**, potential **anemia**, **K+/Mg2+ deficiency, B12, folate**