Cystic Fibrosis + other Bronchiectasis Flashcards
What is cystic fibrosis?
Alteration in the structure and function of CFTR protein –> impaired transport of chloride ions –> production of thick sticky mucous in lungs, pancreas + other organs
What is the most common mutation?
Is is the pattern of inheritance?
F508 deletion Autosomal recessive (1 in 25 carrier)
How is CF diagnosed?
Positive newborn screen (immunoreactive trypsinogen - IRT)
+ve sweat test
genetic testing
What may be seen at birth in a baby with CF?
Delayed passage of meconium (may cause obstruction - meconium ileus)
What are some clinical features of CF?
Failure to thrive (but increased appetite) Wet sounding cough Recurrent chest infections Congenital absence of the vas deferens Steatorrhoea (fat malabsorption) Salty sweat
What does CF look like on a CXR?
BRONCHIECTASIS
usually upper lobe
Describe the exocrine pancreatic failure in CF and how it is treated
Failure of secretion of lipase/amylase –> digestion failure
Treated with CREON (enzyme replacement)
Describe the endocrine pancreatic failure in CF and how it is treated
Destruction of islet cells –> failure of insulin production
Treated with insulin
Describe the pathophysiology of bronchiectasis
Irreversible dilation of the bronchial tree due to chronic infection
Airflow obstruction
Impaired clearance of secretions
What are the clinical features of bronchiectasis?
Chronic productive cough
SOB
Recurrent chest infections
Crackles, high pitched inspiratory squeaks and rhonchi
What are rhonchi?
Sounds like snoring
Due to secretions in large airways
How is bronchiectasis diagnosed?
CT chest –> dilation of bronchi +/- airway thickening
What is the classic sign of bronchiectasis on CT?
Signet ring sign –> bronchi larger than their adjacent pulmonary artery
Name three congenital causes of bronchiectasis
CF
Young syndrome
Kartagner’s syndrome
What are the features of Young syndrome?
Bronchiectasis
Rhinosinusitis
Male infertility