Respiratory - Cystic Fibrosis Flashcards
What is cystic fibrosis?
An autosomal recessive disease leading to mutations in the cystic fibrosis transmembrane regulator (CFTR) gene, leading to:
- thick pancreatic and biliary secretions
- low volume thick airway secretions
- congenital bilateral absence of the vas deferens in males, so infertile
Presentation of cystic fibrosis.
- meconium ileus - occurs when the infants bowel is blocked by sticky secretions, giving signs of bowel obstruction soon after birth.
- intestinal malabsorption - a severe deficiency of pancreatic enzymes causes intestinal malabsorption, which may result in poor growth.
- recurrent chest infection
- newborn bloodsport test
what are the typical signs of cystic fibrosis.
- finger clubbing
- cyanotic heart disease
- nasal polyps
- steatorrhoea
- abdominal sweat secretions
Which tests can be used to diagnose cystic fibrosis?
- newborn blood spot testing
- sweat test (GOLD STANDARD)
- genetic testing for CFTR gene in pregnancy or after birth
Give some common complications associated with cystic fibrosis.
- respiratory infections
- low body weight
- distal intestinal obstruction syndrome (DIOS)
- CF related diabetes
Why do patients with cystic fibrosis suffer chronic chest infection?
CF affects the CFTR transporter, so chloride ions are not transported into the airways. This leads to thick mucus secretions, thus patients struggle to clear their airways.
Chest infections need aggressive therapy with physiotherapy and antibiotics. Prophylactic abx may be prescribed.
Give some common examples of microbial colonisers in cystic fibrosis.
- Staphylococcus aureus
- Haemophilus influenzae
- Pseudomonas aeruginosa
- Escherichia coli
What is distal intestinal obstruction syndrome (DIOS)?
Faecal obstruction in the ielocaecum, due to thick and dehydrated faeces. Cause is usually insufficient prescription of pancreatic enzymes or non-compliance.
Treatment with PO Gastrogafin, which draws water across the bowel wall by osmosis to rehydrate the faeces.
How is cystic fibrosis managed?
- chest physiotherapy
- exercise
- high calorie diet
- CREON tablets (pancreatic enzymes)
- prophylactic flucloxacillin
- bronchodilators (e.g. salbutamol)
- pneumococcal and influenza vaccination
What lifestyle advise should be offered to patients with cystic fibrosis?
- no smoking
- avoid other CF patients
- avoid friends with colds / infections
- avoid jacuzzis (psuedomonas)
- sodium chloride tablets in hot weather or vigorous exercise
What monitoring should a patient with cystic fibrosis receive?
- regular monitoring of sputum for colonisation
Screening for:
- diabetes
- osteoporosis
- vitamin D deficiency
- liver failure
