Chronic asthma

Question 1

Describe the pathophysiology of asthma

Answer 1

• Chronic bronchial inflammation:
  
  • T lymphocytes, mast cells, eosinophils
  • Smooth muscle hypertrophy
  • Epithelial damage
  • Mucus plugging
• Reversible variable airway obstruction
• Airway hyper-responsiveness

Question 2

Name three asthma phenotypes

Answer 2

• Allergic: ^eg. dust mites, pollens, animal
• Non-allergic: chemical and biological products
• Respiratory infection: often starts in middle age
• Exercise-induced
• Brittle asthma: recurrent severe attacks
• Steroid-resistant asthma

Question 3

Define atopy

Answer 3

Genetic tendency to develop allergic IgE-mediated diseases

Includes asthma, allergic rhinitis, and dermatitis/eczema

Question 4

Name four characteristic clinical features of asthma

Answer 4

Episodic or daily/seasonal variation of: worse at night and morning

• Expiratory polyphonic wheeze; respiratory distress
• Cough: often nocturnal
• Chest tightness
• Dyspnoea
• Variable expiratory airflow limitation

Symptoms can be triggered by factors

May resolve spontaneously or with medication

Question 5

Suggest two questions to check for possible occupational asthma

Answer 5

• Are symptoms better on days off work?
• Are symptoms better when on holiday?

Question 6

Outline the diagnostic criteria of chronic asthma in adults

Answer 6

Asthma symptoms plus +ve objective tests

• FeNO: (aged 17+) ≥40 parts per billion (ppb)
• Spirometry: FEV1/FVC <70%
• Bronchodilator reversibility (BDR): ≥12% improvement in FEV1

Consider

• Peak expiratory flow variability over 2-4wks: >20% variability
• Direct bronchial challenge test: PC20 <8 mg/ml

Question 7

Outline the diagnostic criteria of chronic asthma in children

Answer 7

Asthma symptoms plus +ve objective tests

• FeNO: (aged 5-16) ≥35 ppb
  
  • Children if diagnosis uncertain with normal spirometry/-ve BDR test
• Spirometry: FEV1/FVC <70%

Consider

• Bronchodilator reversibility (BDR): ≥12% improvement in FEV1
• Peak expiratory flow variability over 2-4wks: >20% variability

Question 8

Outline the diagnostic criteria for asthma in young children <5yr

Answer 8

• Asthma symptoms on observation and clinical judgement
• Not indicated for objective tests till aged 5

Question 9

Name five possible reasons for uncontrolled asthma

Answer 9

• Alternative diagnoses
• Lack of adherence
• Suboptimal inhaler technique
• Smoking
• Seasonal or environmental factors
• Occupational exposures
• Psychosocial factors

Question 10

List 5 differentials of eosinophilia

Answer 10

• Airway inflammation: asthma or COPD
• Allergic rhinitis
• Allergic bronchopulmonary aspergillosis
• Drugs
• Eosinophilic granulomatosis with polyangiitis
• Eosinophilic pneumonia
• Lymphoma
• SLE
• Hypereosinophilic syndrome

Question 11

Provide instructions for how to use a metered-dose inhaler

Answer 11

1. Shake canister
2. Exhale fully
3. Placed aerosol nozzle in mouth - tight seal
4. Rapid inhalation whilst pressing the aerosol
5. Inhalation complete
6. Hold breath for 10s if possible

Good technique still only inhales 15%. Spacer is useful for children and elderly.

Question 12

Outline the initial management for chronic asthma in adults

Answer 12

• SABA reliever therapy
• Low dose ICS maintenance therapy

Question 13

Outline the initial add-on therapy for chronic asthma after SABA + ICS

Answer 13

Offer leukotriene receptor antagonist (LTRA)

Review response to treatment in 4-8 weeks

Question 14

What is offered for asthma in adults uncontrolled by ICS + LABA?

Answer 14

• Offer LABA in combination with ICS
• Review continuation of LTRA

Question 15

How should asthma therapy in adults be altered if uncontrolled with low dose ICS + LABA?

Answer 15

Change LABA + ICS to a MART (combined LABA + low dose ICS) regimen

Question 16

How is adult asthma therapy changed if uncontrolled by MART regimen?

Answer 16

Either

• Adjust MART to include moderate dose ICS
• Fixed dose regimem moderate dose ICS + LABA, with SABA reliever

Question 17

What changes are made to adult asthma management if uncontrolled by MART with moderate dose ICS or fixed-dose regiment?

Answer 17

Either:

• Fixed dose regimen: high dose ICS, with SABA reliever
• Trial of additional drug ^eg. LAMA or theophylline
• Seek expertise from asthma specialist

Question 18

Outline the initial management of asthma in children

Answer 18

• SABA reliever therapy
• Paediatric low dose ICS

Question 19

What is the next step in childhood asthma management if uncontrolled by SABA + low dose ICS?

Answer 19

Add-on LTRA

Review treatment response in 4-8 weeks

Question 20

How is childhood asthma therapy changed if uncontrolled by LTRA + ICS?

Answer 20

• Consider stopping LTRA
• LABA + paediatric low dose ICS

Question 21

Outline the next step in childhood asthma medication if uncontrolled by LABA + paediatric low dose ICS

Answer 21

Change ICS + LABA to a MART regimen (combined low dose ICS + LABA)

Question 22

How is childhood asthma treatment changed is uncontrolled by MART (combined low dose ICS + LABA)?

Answer 22

Either

• Adjust MART to contain paediatric moderate dose ICS
• Fixed-dose regimen of moderate dose ICS + LABA, with SABA reliever

Question 23

What is the next step if childhood asthma is uncontrolled with MART (combined moderate dose ICS + LABA) or fixed-dose regimen?

Answer 23

Either:

• Seek expert advise from asthma specialist
• Fixed-dose regiment of paediatric high dose ICS with SABA reliever
• Trial additional drug ^eg. theophylline

Question 24

Give three self-management steps for asthma management

Answer 24

• Asthma self-management programme
  
  • Personalised action plan
  • Education
  • Increased dose of ICS (adults) for 7d if asthma deteriorates
• Weight loss
• Smoking cessation
• Breathing exercise programmes

Question 25

Outline the management for asthma in young children \<5yrs

Answer 25

SABA reliever ± maintanence therapy: 1. 8/52 trial of paediatric moderate dose ICS * Not resolved: likely alternative diagnosis * Recurred within 4/52 after trial: paediatric low dose ICS * Recurred beyond 4/52 after trial: repeat trial of ICS 2. Consider additional LTRA 3. Stop LTRA and refer to asthma specialist