Cystic Fibrosis Flashcards
What is cystic fibrosis?
Cystic Fibrosis (CF) is an inherited autosomal recessive disease that disrupts ion transport in epithelial-lined organs, including pulmonary airways, sweat ducts, pancreatic ducts and intestine
Where is the mutation for CF?
Long arm of chromosome 7 (Delta F508 deletion most common)
Which gene is associated with CF?
CFTR: Cystic Fibrosis Transmembrane Regulator
a cAMP regulated epithelial chloride channel in apical cell membranes
T or F: there are varying degrees of loss of function of the CFTR gene associated with five classes of mutations
T: I - no synthesis II - block in processing III - block in regulation IV - altred conductance V - reduced synthesis
Which class of mutation is more severe?
I to III more severe
What is the Delta F508 mutation?
Deletion of 3 nucleotides that encode phenylalanine in position 508
T or F: CF occurs in Caucasian and European descent more frequently than other groups
T
What is the pathophysiology of CF?
Abnormal chloride channels on the apical surface of epithelial cells ---> Depleted airway surface layer --> defective mucociliary transport and accumulation of mucus --> Clogged ducts Thick, sticky secretions --> Airways: -Sinus disease -Lung disease
GI tract
- Pancreatic disease
- Constipation/bloating
Liver and biliary disease
Male infertility
Salty sweat
What are the clinical hallmarks of CF?
Recurrent lung infections, often with unusual pathogens (funny bugs)
Obstructive airways disease – cough, thick sticky sputum, wheeze, dyspnea
Low BMI
Progression to lung disease
What is the classic CF phenotype [2 severe mutations]?
Early age of diagnosis
Pancreatic insufficient
Elevated sweat chloride
What is the atypical CF phenotype [ie. 1 mild mutation]?
Diagnosed at an older age
Pancreatic sufficient
Sweat chloride levels closer to normal
What are the upper airway conditions related to CF?
Sinusitis
Nasal polyps
What are the lower airway conditions related to CF?
Chronic productive cough Recurrent respiratory infections (Pulmonary exacerbations): - pseudomonas aeruginosa - staphylococcus aureus Hemoptysis Pneumothorax Exercise intolerance
What are radiographic findings for CF?
Bronchiectasis (permanent enlargement of parts of the airways of the lung)
Hyperinflation
Fibrosis
What is the common GI finding with CF?
DIOS (Distal intestinal obstruction syndrome)
