Random Physio / Biochem Flashcards
Physio - 1 Q Biochem - 4Q
- presentation of CF pts
- How to test for CF
- Heat stroke + salt depletion
High (>60mM) [Na+] in sweat (normal <40mM) - Pilocarpine (M3 ag); iontophoresis stimulation test
Cystic Fibrosis Gene:
- Affected organs
- End-stage presentation of CF pt
- Mutation
- Protein polarization
- Pancreas, sweat gland, lung, intestine, repro tract, heart, kidney
- Lung = end-stage. If they survive this, end-stage = kidney + LVH (??)
- Deletion of ΔF508 (phenylalanine) @ BOTH alleles
- ATP-binding Cassette (ABC) that is ALWAYS on apical membranes of epithelium
Cystic Fibrosis protein rating
Rated between Class I-VI
I - NO protein (worst)
VI - accelerated turnover (best)
Protein functions via PKC & PKA
Cystic Fibrosis protein:
normal vs mutated
@ 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)
Major effects of CF
- Mucus blocks airway -> bronchiectasis, infx, pneumonia
- Steatorrhea, decr. fat soluble vits / protein / carbs
- Fluid hyperabsorption -> meconium ileus
***FIRST SIGN
Pharmacotherapy of Cystic Fibrosis
Airways made to prevent uptake of foreign material
Mucolytics
Anticholinergics
DNAse
B-adrenergics
Aerosolized Saline (Hypertonic)
TOC: Percussion
MUTYH (mutY-homolog)/MAP
- Inheritance pattern
- Clinical signs
- Autosomal RECESSIVE
- 10+ polyps
What is the most sensitive diagnostic method of Lynch Syndrome?
Microsatellite instability + followup tests
will show extra microsatellite bands due to mismatch repair deficiency
(Criteria are specific, but lots of false negatives)
What is the Amsterdam-II criteria for Lynch Syndrome?
3-2-1: all at same time
3+ relatives w/Lynch-type cancers
2 generations
1 diagnosed before 50y
What are the first and second hits of Mismatch repair mutation?
What disease is associated with this mutation type?
Lynch Syndrome (HNPCC)
- First hit: Inherited mutation (MSH2, MLH1)
- Independent mutation / LOH / Methylation & inactivation of promotor
What are the diagnostic clues of Lynch Syndrome?
- Young age
- Family hx with CRC
- 7-10% have more than 1 tumor at initial diagnosis (sporadic CRC is highly unlikely to have +1)
- Different histology
**can also cause endometrial or other cancers
What is Loss of Heterozygosity?
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)
Familial Adenomatous Polyposis (FAP)
- Clinical signs
- Genetics
- >100 polyps
Fe-defx Anemia
Avg age 45y - AD mutation of APC tumor suppressor gene
De novo inheritance in 1/4 cases
Somatic mutation has fewer polyps
What are clinical signs of APC gene mutation carriers?
- Polyps in upper GI, duodenum
- Congenital Hypertrophy of Retinal Pigment Epithelium (CHRPE)
- multiple patches are pretty specific for APC mutation
- Extra-intestinal cancers

What type of genes do inherited cancers affect?
Tumor Suppressor genes
Familiar cancers– more likely to be sporadic or inherited?
Sporadic… but has been proven to have genetic predisposition
Mild hepatitis:
S/S
Dietary management
S/S: ill-looking, loss of appetite
Diet: light, high in proteint, do NOT RESTRICT FAT (reccomment milk, butter, cheese)
Chronic active hepatitis
S/S
Dietary management
- Exhaustion, fluctuating jaundice
- Ascites (later stages)
For ascites: bed rest + low-sodium diet with fluid restriction
Alcoholic Hepatitis: dietary management
High protein and energy
Multivitamin with Thiamine + folate
Cholecystitis:
S/S
Dietary management
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?!)
Hepato-renal Failure: dietary management
Sodium & Protein restriction
Biliary Cirrhosis:
Dietary management
Low fat diet
Medium-chain triglyceride supplement
When is a low fat diet advised?
When is a low protein diet avised?
Low fat: biliary cirrhosis
Low protein: Hepato-renal failure
Pre-op Bariatric Surgery diet
- 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.
Post-op Bariatric Surgery Diet
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