Cystic Fibrosis

Question 1

Cystic Fibrosis is

Answer 1

an autosomal recessive genetic condition affecting the mucus glands.

Question 2

It is characterised by defects in the

Answer 2

CFTR on chromosome 7.

Question 3

CFTR codes for

Answer 3

Cystic Fibrosis Transmembrane conductance Regulator protein.

Question 4

The CFTR protein regulates

Answer 4

the flow ions, particulary chloride, across cell membranes

Question 5

Most common variant is

Answer 5

the delta-F508 mutation , in the CFTR gene.

Question 6

The delta-f508 mutation causes

Answer 6

productions of thick vicious mucus in organs such as, lungs, pancreas, and reproductive tract.

Question 7

Prevalence

Answer 7

1in 25 are carries of the mutation.

1 in 2500 children have CF.

Question 8

Accumulation of mucus can cause

Answer 8

obstructions in the airways, leading to respiratory problems. Such as: bacterial colonisation, chronic lung infections and bronchiectasis.

Question 9

CF can also cause (Malnutrition)

Answer 9

pancreatic insufficiency, resulting in malnutrition and impaired fat and protein absorption.

Question 10

In the reproductive system, CF can cause

Answer 10

congenital bilateral absence of vas deferens in males, resulting in male infertility

Question 11

Secretions in airways creates (environment)

Answer 11

the perfect environment with plenty of moisture and oxygen for colonies of bacteria to live and replicate.

Question 12

Common colonisers include

Answer 12

Staphylococcus aureus

Pseudomonas aeruginosa

Question 13

Once patients become colonised with pseudomonas it can be difficult to

Answer 13

get rid of, thus long-term nebulised antibiotics, such as ciprofloxacin can be used

Question 14

Diagnosis of CF in babies

Answer 14

typically screened for at birth using the newborn blood spot test.

20% of babies with CF have meconium ileus (condition where the meconium is thick and sticky, causing it to get stuck and obstruct the bowel).

Meconium ileus is pathognomonic for CF.

Question 15

Gold standard diagnosis

Answer 15

Gold standard = the sweat test - measures concentration of chloride in the sweat.

The diagnostic chloride concentration for CF is no more than 60mmol/L.

Question 16

Diagnosis techniques include what three

Answer 16

clinical presentation, laboratory tests and genetic testing

Question 17

Physical examination may reveal

Answer 17

recurrent respiratory infections, poor growth and development (failure to thrive), steatorrhea, thick sputum production, crackles and wheezes on auscultation, nasal polyps, pancreatitis and salty skin.

Question 18

Lab tests also include

Answer 18

measurement of serum electrolytes particularly chloride levels

analysis of stool samples for pancreatic enzymes levels.

genetic testing can confirm the diagnosis by identifying pathogenic mutations in the CFTR gene.

Question 19

Management involves (A to H)

Answer 19

A - antibiotics (to treat bacterial infections)

B - bronchodilators (to improve airway function)

C - chest physiotherapy (essential to clear mucus and reduce risk of infection and colonisation)

D _ digestive enzymes (CREON tablets replace missing lipase enzymes)

E - exercise (improves respiratory function)

F - flu vaccines and pneumococcal

G - growth hormones

H - high calorie diet.

Question 20

Goal of treatment (PMI)

Answer 20

manage symptoms, prevent complications, and improve quality of life.

Question 21

Further treatments include

Answer 21

lung transplantation (end of life care)

liver transplant (liver failure)

fertility treatment

genetic counselling

Question 22

Monitoring

Answer 22

follow up appointments every 6 moths for the monitoring of sputum colonisation of bacteria like pseudomonas

screening for diabetes, osteoporosis, vit D deficiency and liver failure.

Question 23

Life expectancy

Answer 23

CF trust gives a median life expectancy of 45 years

Question 24

CF pathophysiology sum up

Answer 24

is an autosomal recessive genetic condition affecting the mucus glands. It is caused by a genetic mutation of the cystic fibrosis transmembrane conductance regulatory gene on chromosome 7. There are many different mutations the most common is the delta- F508 mutation. This gene codes for the cellular channels, particularly the chloride channel.

Question 25

Aetiology of CF

Answer 25

Gene mutation of the CFTR gene on chromosome 7

Genetic component

Recessive = child needs to inherit one copy from each parent

Question 26

Risk Factors of CF

Answer 26

Family history

Most common in Northern European Ancestry

Question 27

CF diagnosis

Answer 27

New-born blood spot testing - performed at birth

The sweat test is gold standard

Genetic testing for the CFTR gene can be performed via amniocentesis or chorionic villous sampling or blood test

meconium ileus is pathognomonic for cf

Question 28

CF Key-biochem

Answer 28

Chloride concentration is more than 60mmoL/L

Question 29

CF clinical features (long list)

Answer 29

Chronic cough

Meconium ileus

Thick sputum production

recurrent respiratory tract infections

steatorrhoea - due to lack of fat-digesting enzymes

abdominal pain and bloating

salty skin

failure to thrive

pancreatitis

nasal polyps

finger clubbing

crackles and wheezes on auscultation

abdominal distention

Question 30

CF medication

Answer 30

CREON tablets = digest fats in patients with pancreatic insufficiency (these replace missing lipase enzymes)

Prophylactic flucloxacillin - reduces risk of infections like staph aureus

Nebulised DNase - breaks downs DNA material in respiratory secretions less viscous and easier to clear

Nebulised hypertonic saline

insulin - 50% of adults with CF develop cystic fibrosis-associated diabetes

Question 31

CF Management (A to H)

Answer 31

A - Antibiotics

B - Bronchodilator, subutamol inhalers

C - Chest physiotherapy

D_ Digestive enzymes - CREON tablets to replace missing lipase enzymes

E - Exercise, improves function

F - Flu + pneumococcal vaccine

G- Growth hormone

H - High calorie diet

Question 32

Surgery options for CF

Answer 32

Lung transplant (option in end-stage respiratory failure)

Liver transplant in liver failure