Cystic Fibrosis: Case Study Flashcards
What is done at birth?
1st
Heel prick test
= test for IRT levels
= immuno reactive trypsinin
What is trypsinin?
Pro-enzyme
= enzyme that is NOT active
Activated by trypsin in small intestine
What is then done if IRT levels come back elevated?
Sweat chloride test
What is the level of sweat chloride if CF?
2nd
> 60 mmol/L
What is then done if sweat test is elevated?
3rd
Genetic test to identify if genetic mutation is present
What is the pancreas’ endocrine function?
Release hormones
eg. insulin
What is the pancreas’ exocrine function?
Release enzymes
What happens to pancreas in CF patient?
Pancreatic duct blocked by mucus
= enzymes blocked
= accumulate
What happens if enzymes are stuck in pancreas?
Carbs, proteins + fats cannot be broken down
= nutrients cannot be absorbed
What therapy is immediately offered?
Early nutrition
Liquid multivitamins
Replacement of enzymes
Prophylactic antibiotics
What is an example of replacement of enzymes drug?
Creon
What is the problem with Creon?
Enteric coating
= need to be given with acidic food
= or protease will degrade the mouth
Babies can’t be given tablets
What do you monitor in patient’s with CF?
Height + weight
Pulmonary status
Oropharyngeal cultures
Glucose tolerance testing
Bone density
How is pulmonary status tested?
FEV1
= forced expiratory vol in 1s
Why is oropharyngeal cultures collected?
Testing for bacteria
Why is glucose tolerance tested?
Pancreas NOT working
= chance of developing diabetes
Why is bone density tested?
NO nutrition
= chance of osteoporosis
What % of FEV1 is considered respiratory failure?
30%
Why is inhalation of hypertonic saline sometimes given to CF patients?
Help liquify mucus
= can cough it up
What is Dornase alfa?
Enzyme
Recombinant form of human deoxyribonuclease
What does Dornase alfa do?
Breaks up cellular DNA from neutrophils
= decreases mucus viscosity
How does cellular DNA of neutrophils end up in lungs?
Bacteria trapped in lungs
= neutrophils stimulated
= trapped
= die (apoptosis)
= DNA released
= increase viscosity of mucus
What is Pseudomonas aeruginosa?
Gram negative
CF patients will eventually get it at one point
What is the problem with Pseudomonas aeruginosa?
Difficult to treat
= resistant to most antibiotics
What is often prescribed to treat Pseudomonas aeruginosa in CF patients?
Oral ciprofloxacin for 3 weeks
Nebulised tobramycin 300mg for 1 month
After negative, ciprofloxacin stopped BUT tobramycin continued for 1 month
What is the problem with quinolones?
Caution in children
= joint problems
Why are quinolones used then in CF paediatric patients?
CF outweighs the problems
What type of antibiotic is ciprofloxacin?
Quinolone
What type of antibiotic is tobramycin?
Aminoglycosides
What type of antibiotic is azithromycin?
Macrolide antibiotic
Why is azithromycin sometimes used as “500mg 3x a week”?
Has inflammatory properties at that dose + regime
What is the normal level for 2-hr OGTT plasma glucose?
<11mmol/L
= higher diabetes/pancreas not working?
What is the normal level for 2-hr OGTT plasma glucose?
<11mmol/L
= higher diabetes/pancreas not working?
What is HbA1c?
Sugar stuck on Hb
What is the normal level for HbA1c?
<6%
What does microalbuminuria suggest?
Protein in urine
= signs of renal failure
Which gene is mutated in CF?
CFTR
What does CFTR code for?
Cl channels
What happens when we sweat?
Release Na+, Cl- + H2O
Na channel = Na+ reabsorbed
Cl channel = Cl- reabsorbed = NORMAL person
What happens because Cl- is NOT reabsorbed?
= Na+ NOT reabsorbed
= NaCl excreted out = salty sweat
= H2O follows salt
= dehydration
What happens because H2O leaves in CF patients?
Mucus gets thick + sticky
= mucus cannot be cleared
= bacteria cannot be cleared
= stuck in lungs
