Cystic Fibrosis Flashcards
What is Cystic Fibrosis?
One of the most common autosomal recessive inherited disease, found in Caucasians.
What are the symptoms of Cystic Fibrosis?
Lung infections or pneumonia. Wheezing. Coughing with thick mucus. Bulky, greasy bowel movements. Constipation or diarrhoea. Trouble gaining weight or poor height growth. Very salty sweat.
What is the CFTR gene?
Cystic Fibrosis Transmembrane Regulator (CFTR) Gene.
Over 1,900 gene variants
CFTR channel function:
Responsible for the protein that regulates Chloride and Bicarbonate transport.
What do impaired or absent transport of chloride, sodium and bicarbonate ions lead to:
Thick viscous secretions.
Increased salt content in sweat gland secretions.
What is the timeline of effects of CF?
Newborn: Meconium ileus
Young children: Pancreatic insufficiency, malabsorption, respiratory symptoms.
Older children & young adults: Recurrent respiratory infections, pancreatitis/diabetes, infertility in males.
Thirty onwards: Atypical respiratory infections, recurrent nasal polyps, liver disease.
What factors influence CF presentation?
Genetics Internal External Environmental Lifestyle Social / Economic background
What is Pseudomonas aeruginosa?
Chronic Infection.
Major pathogen causing morbidity and mortality.
Determines the patients’ quality of life and long-term survival.
Aggressive treatment of first isolates.
Avoid colonisation.
How do you treat chronic infection?
Early treatment with anti-pseudomonal antibiotics.
Prophylactic antibiotics used to reduce the frequency of exacerbations.
Nebulised antibiotics – colistin, tobramycin.
IV antibiotics for exacerbations.
What are the advantages of nebulised antibiotics?
Higher concentration of drug in airways.
Easier to administer at home.
Reduces the need for IV antibiotics.
Fewer systemic side effects.
What are the disadvantages of nebulised antibiotics?
May cause bronchospasm (use after physio/bronchodilators).
Environmental contamination/resistance.
Compliance.
When would IV antibiotics be used?
Used if infection is persistent.
Minimum 10-14 days duration.
Usually use a combination of 2 antibiotics with different mechanisms of action.
Synergy with β-lactams and aminoglycoside.
Increased risk of toxicity from repeated courses.
Therapeutic Drug Monitoring essential.
Intravenous access.
What are mucolytics?
They facilitate mucociliary clearance and expectoration by reducing sputum viscosity.
When would bronchodilators be used?
Use nebulised bronchodilators before nebulised antibiotics or physiotherapy.
Regular inhaled short and long-acting b2-agonists may be beneficial.
Asthmatic component of CF – management as per asthma guidelines.
What are some hepatobiliary complications?
Fatty infiltration ——> cirrhosis.
Vitamin K suppl. (as menadiol).
Thickened mucus in biliary ducts.
Causes “biliary sludging”.
How does CF affect GORD?
Increased incidence in CF.
Hyper-acidity secretions.
Increased abdominal pressure.
Constipation.
Treat as any patient with reflux.
PPI/H2 antagonist may enhance efficacy of pancreatic enzyme supplements.
