The Child with Cystic Fibrosis

Lydia Burland

Learning Outcomes

By the end of the session you should;

Know the basic physiology underlying CF

Recognise how CF presents in different age groups

Be able to interpret simple investigations in CF

Be aware of different management options

Know about common complications

Cystic Fibrosis: Key Facts

Most common inherited condition in the Caucasian population

Affects 1 in 2,500 live births

Autosomal recessive inheritance

Due to CFTR gene mutation on chromosome 7

Over 1,500 mutations have been identified

The only risk factor is a positive family history

Pathophysiology

CFTR is an ATP-responsive chloride channel

It is involved in;– Sodium transport across epithelia– Anti-bacterial defences– Cell surface composition

An abnormal CFTR results in;– Dehydration of epithelial surfaces– Viscous secretions– Increased bacterial colonisation

Presentation

How does CF present in childhood?

Presentation

Neonatal period;

Screening Prolonged jaundice

Meconium ileus Haemorrhagic disease

Infancy and childhood;

Recurrent LRTI FTT

Diarrhoea Chronic cough

Rectal prolapse Steatorrhoea

Nasal polyps Acute pancreatitis

Meconium Ileus

15-20% of newborns

Presents with;

– Bilious vomiting

– Abdominal distension

– Delayed passage of meconium

Treatment includes gastrograffin enema +/- surgery

Respiratory Disease

Dry sticky secretions lead to;

– Decreased mucociliary clearance

– Chronic infection and inflammation

– Bronchiectasis

Common pathogens include;

– Staph. Aureus

– Haemophilus influenzae

– Pseudomonas aeruginosa

– Burkholderia cepacia

On Examination

Signs + symptoms;

- Clubbing

- Cough

- Purulent sputum

- Crackles

- Wheeze

- Obstructive FEV1

Pancreatic Insufficiency

>90% of CF patients

Thick secretions block pancreatic ducts

Pancreatic enzymes then cause local cell damage

This results in;

– Malabsorption

– Insulin dependent diabetes mellitus

Investigations

What tests are used to diagnose CF?

Investigations

Usually identified on the newborn Guthrie test

Sweat testing is the gold standard for diagnosis

Other investigations include;

– Genetic testing (>1500 known mutations)

– Faecal elastase

– Sinus x-ray or head CT

– CXR and CT thorax

– Sputum microbiology

Management Strategies

Multidisciplinary team management from diagnosis

Prophylactic flucloxacillin to prevent staph. aureus infection

Immunisations + annual flu vaccine

Avoid smokers, early nursery + bugs

Management Strategies

Physiotherapy;– By parents and professionals

– Increases clearance of secretions

– Reduces airway obstruction

– Maintains respiratory function and exercise tolerance

DNase or hypertonic saline to loosen secretions

High energy diet

Creon + vitamins A, D + E supplements

Management of Acute Infection

Acute infection;

– 10-14 days of oral abx

– If failure to respond or very unwell admit for IV abx

1st episode of pseudomonas;

– 3 months of oral ciprofloxacin + inhaled colomycin

Chronic pseudomonas;

– Regular elective admission for IV abx +/- nebulised colomycin

Complications

Constipation

CF-related diabetes

Biliary cirrhosis

Osteoporosis

Psychosocial issues

Prognosis

Younger patients have better outcomes due to improved therapies

Morbidity is usually due to chronic pulmonary sepsis

Life expectancy is now >45 years

The future includes new gene therapies and drug modulation of the CFTR protein

In Summary

CF is common in Western populations

It is a multisystem disorder

Early diagnosis and management improves outcomes

Best managed by an MDT in a tertiary centre

Requires significant education and support for families

Questions

1. What percentage of people in the UK are carriers of the mutated CF gene?

a. 1 in 10 b. 1 in 25

c. 1 in 100 d. 1 in 250

2. A sodium level ____ is diagnostic of CF?

a. >30mmol/L b. >40mmol/L

c. >60mmol/L d. >100mmol/L

Questions

3. Which antibiotic is given as prophylaxis from diagnosis?

a. Amoxicillin b. Colomycin

c. Ciprofloxacin d. Flucloxacillin

4. What does the above antibiotic aim to prevent?

a. Pseudomonasb. Strep. pneumoniae

c. Staph. aureus d. Haem. influenzae

Questions

5. What organism is responsible for chronic pulmonary infection in CF?

a. Pseudomonas b. Strep. pneumoniae

c. Staph. aureus d. Haem. influenzae

6. The most common CF mutation is ___?

a. F508 b. βF508

c. αF508 d. μF508

Answers

1. What percentage of people in the UK are carriers of the mutated CF gene?

a. 1 in 10 b. 1 in 25

c. 1 in 100 d. 1 in 250

2. A sodium level ____ is diagnostic of CF?

a. >30mmol/L b. >40mmol/L

c. >60mmol/L d. >100mmol/L

Answers

3. Which antibiotic is given as prophylaxis from diagnosis?

a. Amoxicillin b. Colomycin

c. Ciprofloxacin d. Flucloxacillin

4. What does the above antibiotic aim to prevent?

a. Pseudomonasb. Strep. pneumoniae

c. Staph. aureus d. Haem. influenzae

Answers

5. What organism is responsible for chronic pulmonary infection in CF?

a. Pseudomonas b. Strep. pneumoniae

c. Staph. aureus d. Haem. influenzae

6. The most common CF mutation is ___?

a. F508 b. βF508

c. αF508 d. μF508

Thanks