17. Cystic Fibrosis Flashcards
What is Cystic Fibrosis
- also called mucoviscidosis
- congenital disease/generalized hereditary disorder associated with widespread dysfunction of the exocrine gland system (everything that sweats)
- destroys pancreas; lungs full of cysts, fibrosis, pus
Abnormal CFTR
pathophysiology which bring progressive lung disease is due to impact of abnormal CFTR function on airway surface liquid (ASL)
Cystic Fibrosis - Genetics
autosomal recessive disorder caused by mutations in a single gene on the long arm of chromosome 7 that encodes the CTFR protein
- variation is due to CFTR function expression
- most common variant: Delta-508
Colour of mucus
indicates severity and length that mucus has been in airway
Types of Gene Mutations in CF
- Door-Jamming Mutation/G551D (3%)
- Common Delta F508mutation (90%) - CFTR protein is made, but it just floats around inside the cell without reaching the surface
Main descriptor of CF
- exocrine gland disorder (everything that sweats is affected)
Classical Clinical Features: Chronic Sinopulmonary disease
- Persistent colonization/infection
- Chronic sinus disease: nasal polyps (growth inside nose), radiographic changes
Classic Clinical features: Endobronchial disease
- cough and sputum production
- wheeze and air trapping in the lungs (like COPD at 5 years old)
- Radiographic abnormalities
- Digital clubbing due to right-sided heart failure
Classic Clinical features: obstructive or restrictive
Obstructive pulmonary disease of PFTs
- become obstructive and restrictive
Clinical features: growth
failure to thrive due to protein-caloric malnutrition (PEM)
- failure to grow and maintain muscle mass
Clinical features: GI/nutritional abnormalities in infants
- Meconium ileus: so thick in infants with CF that they’re unable to have bowel movement due to lack of digestive enzymes
- Steatoorrhea (fatty stools that float). Fat soluble enzyme deficiencies (A, D, E, K)
Clinical Features: GI/pancreas (youth)
- recurrent pancreatitis/exocrine pancreatic insufficiency
- Distal intestinal obstruction syndrome (require digestive enzymes)
- Rectal prolapse (extreme: during end stage or skinny babies > malnourished > no muscle mass > rectum pops out due to large stool and no muscle mass)
Clinical Features: Azoospermia
Obstructive Azoospermia in males (cannot produce sperm, exocrine gland)
Clinical Features: salt
- acute salt depletion
- chronic metabolic acidosis
Clinical Features: vitamins
- fat soluble enzyme deficiency (A, D, E, K)
- Cannot absorb vitamin D results in osteoporosis and random joint inflammation
- lack of vitamin K: coughing out blood
- Delayed growth and puberty
Clinical features: diabetes
due to pancreas being affected
- women more affected by having diabetes
Clinical features: bony pathology
- vertebral compression and rib fractures
- increased thoracic kyphosis
- pressure on spine with coughing (easy to fracture with a cough)
- reduced lean muscle mass
Clinical features: CXR
- bronchiectasis
- hyperinflation
- RUL lesion
- Barrel Chest
- Bull eyes or pockets of cysts in the lungs (pus)
Diagnosing CF (newborns, sweat, fecal, CTFR, vitamins, bones, CT)
- all newborns tested in Alberta for gene (immunoreactive trypsogin)
- Sweat chloride test (normal rage 1-50)
- Fecal fat test (72 hour stool collection)
- CTFR dysfunction test
- General lab work for vitamin levels
- CT scan for chest and pancreas
- Bone density
When can we do coughing/suction in CF
only when hemoptysis stops
Trademark feature in the nose
sinus polyps
- chronic snoring
Pulmonary Manifestations: newborns
- lungs and mucosal glands appear normal at birth
- gradual increase in mucosal glands suggesting early mucus plugging precedes evidence of inflammation or infection
- soon after birth, infection + bacterial pathogens commences with intense neutrophilic response, over time the airway becomes dilated and bronchiectatic
Pulmonary manifestations: late stage
- lung parenchyma becomes affected by atelectasis, pneumonia, and encroachment by enlarging airways
- bronchiectasis causes hypertrophy of bronchial circulation and bronchial cysts
Common respiratory symptoms
respiratory symptoms show at less than 6 months of age with:
- tachypnea
- wheezing
- increased WOB
- hyperinflation
- productive cough
- clubbed fingers
