Cystic Fibrosis and Bronchiectasis

Question 1

Cystic fibrosis is a gene mutation on what chromosome?

Answer 1

Chromosome 7

Question 2

CFTR

Answer 2

Cystic fibrosis transmembrane conductance regulator

Question 3

What does the CTFR channel do?

Answer 3

Control movement of salt and water across epithelial membranes.

Question 4

What is the effect on having mutations to the CFTR gene?

Answer 4

Mutation causes increased sodium and chloride content in sweat and increased resorption of sodium and water from respiratory epithelium.

Question 5

Dehydration of the respiratory epithelium is thought to cause what?

Answer 5

Chronic bacterial infection and ciliary dysfunction leading to bronchiectasis.

Question 6

Other than the lungs CFTR mutations affects where in the body?

Answer 6

Gut epithelium, pancreas, liver and vas deferens in the reproductive tract.
Diabetes.
Osteoporosis.

Question 7

How are sodium and chloride affected by CFTR mutation?

Answer 7

Reduced chloride secretion out into the respiratory epithelium.
Excessive sodium resorption.

Question 8

Explain the screening programme for cystic fibrosis.

Answer 8

Neonatal screening is done which tests the blood for IRT (immuno-reactive trypsin) - reduces delayed diagnosis and improves patient outcomes.

Prenatal testing is offered to those high at risk.

Question 9

What are the clinical features of cystic fibrosis?

Answer 9

Bronchiolar inflammation and infections leading to bronchiectasis.
Infertility (in men).

Question 10

What is the main bacteria that poses a threat to people with CF?

Answer 10

P. aeruginosa

pseudomonas

Question 11

P. aeruginosa is gram what?

Answer 11

P. aeruginosa is grame negative bacilli.

Question 12

How can cystic fibrosis cause respiratory failure?

Answer 12

Recurrent exacerbations of bronchiectasis cause progressive lung damage, eventually resulting in death due to respiratory failure.

Question 13

What are the gastrointestinal complications of cystic fibrosis?

Answer 13

Malabsorption and steatorrhoea
Biliary cirrhosis
Gall stones
Portal hypertension

Question 14

`How is cystic fibrosis best managed?

Answer 14

Chest physiotherapy
Exercise
Nutrition
Infections are managed with antibiotics.

Question 15

What complications with antibiotics do people with cystic fibrosis face?

Answer 15

The bronchi of patients with CF become colonised with bacteria resistant to antibiotics.

Question 16

Why is malabsorption seen in patients with CF?

Answer 16

Due to exocrine pancreatic failure.

Note: This is treated with oral pancreatic enzymes and vitamin supplements and supplementary feeding.

Question 17

What longer term treatments are available to people with CF?

Answer 17

Ivacaftor, Lumacaftor and Tricaftor.

Question 18

What type of mutation of CF does Ivacaftor treat?

Answer 18

Class 3

Question 19

Explain the gene targeted therapy for cystic fibrosis.

Answer 19

Somatic gene therapy is under development for CF. Manufactured normal copies of the CFTR gene are packaged into liposomes or virus vectors and administered into the airways via aerosol inhalation.

Question 20

What is meant by bronchiectasis?

Answer 20

Abnormal dilation of the bronchi.
- Chronic suppurative airway infection with sputum production and progressive scarring and lung damage occur whatever the cause.

Question 21

What are the clinical feature of bronchiectasis.

Answer 21

Cough
Sputum production
Pleuritic pain
Haemoptysis
Halitosis
Shortness of breath

Question 22

Haemoptysis

Answer 22

Coughing up streaks of blood common larger volumes with exacerbations of infections.

Question 23

Class 1 CF

Answer 23

No CFTR protein is produced.

Question 24

Class 2 CF

Answer 24

No delivery of the CFTR protein to the cell surface.

Question 25

Class 3 CF

Answer 25

Impaired opening of the chloride ion gated channel.

Question 26

Class 4 CF

Answer 26

Decreased function of the CFTR protein.

Question 27

Class 5 CF

Answer 27

Reduced quantity of functional CFTR produced by the cell.

Question 28

Class 6 CF

Answer 28

CFTR protein is less stable.

Question 29

Which CF class mutation is most common?

Answer 29

Class 2

Question 30

Which CF class mutations are most severe?

Answer 30

Class 1 and 2

Question 31

Which CF class mutation is there new groundbreaking treatment for and what is the treatment?

Answer 31

Class 3 - Tricaftor / Ivacaftor

Question 32

How is the composition of airway surface liquid affected in CF?

Answer 32

The ASL is dehyrdrated.

Question 33

How is the muco-ciliary escalator affected in CF?

Answer 33

Thin periciliary layer.
Thicker mucus layer.
Problems with the muco-ciliary escalator thus physiotherapy for muco-ciliary clearance is essential.

Question 34

Foreign particles trapped in the muco-ciliary escalator end up where?

Answer 34

Entering the oesophagus and then into the stomach where they are destroyed by the acidic conditions in there.

Question 35

What can cause bronchiectasis?

Answer 35

Ciliary dyskinesia
Cystic fibrosis
Airway obstruction (e.g by tumour)

Question 36

How can ciliary dyskinesia cause bronchiectasis?

Answer 36

Cilia don’t move normally so the mucus is static. Bacteria in the mucus are able to multiply which can cause pneumonia.
- This can eventually lead to chronic inflammation.

Question 37

Why is the chronic inflammation caused in bronchiectasis a problem?

Answer 37

Release of cytokines which can damage the ciliated epithelial cells and destroy the elastin. Eventually the airways become dilated and clogged with mucus.

Question 38

How is bronchiectasis diagnosed?

Answer 38

CT scan of the bronchioles (bronchioles appear dilated).

Pulmonary function testing - showing decreased lung capacity and decreased FEV1.

Question 39

What is the treatment for bronchiectasis?

Answer 39

Antibiotics to treat the infections of pneumonia.
Postural drainage.
In situation of obstruction e.g tumour surgery may be needed.