1. Dr Rossa Brugha Clinical Research Fellow 11th February 2014
Paediatric Asthma
Dr Rossa Brugha
Clinical Research Fellow
11th February 2014
April 2010

2. Paediatric asthma What is asthma in childhood?
Pathology, signs and symptoms
Diagnosis
Principles of asthma management
Self management
Pharmacotherapy
Assessing control
What’s new

3. The scale of the problem
% of 12 yr. olds
Burr et al Thorax 2006;61:296-9
1 in 11 children and 1 in 12 adults in the UK are currently diagnosed with asthma; that’s 1.1 million children and 4.3 million adults. On average, two children in every school class have asthma – it is the commonest chronic illness in childhood.
While for most people their asthma can be controlled with inhalers, over 1,000 people in the UK died from their asthma in That’s 3 people per day on average.
14 of those deaths were children under 12 years of age. A child is admitted to hospital with asthma every 17 minutes.
The NHS spends around £1 billion on asthma and asthma treatments, 1% of the total NHS budget on just one disease.

4. Eder W et al. N Engl J Med 2006;355:2226-2235.
Changes in the Prevalence of Diagnosed Asthma and Asthma Symptoms over Time in Children and Young Adults.
The scale of the problem
Figure 1. Changes in the Prevalence of Diagnosed Asthma and Asthma Symptoms over Time in Children and Young Adults. Data in Panel A are from Australia,2– 6 the United States, 7 Canada, 8, 9 Switzerland, 10 Germany, 11– 15 the United Kingdom, 16– 23 Norway, 24– 27 Finland, 28, 29 Estonia, 30, 31 Poland, 32 Italy, 33, 34 Spain, 35 Israel, 36, 37 Singapore, 38 Hong Kong, 39, 40 Taiwan, 41 and Korea. 42 Data in Panel B are from Australia, 2– 5 the United States, 43 Switzerland, 10 Germany, 11, 13, 15, 44 the Netherlands, 45 the United Kingdom, 16– 23, 46– 49 Sweden, 50 Norway, 25– 27 Estonia, 30, 31 Italy, 33, 51 Spain, 35 Singapore, 38 Hong Kong, 39, 40 and Korea. 42
Eder W et al. N Engl J Med 2006;355:

5. Asthma vs preschool wheeze
Above age 5
Approx 1 in 11 children
Inflammatory condition
Responds to inhaled corticosteroids
Age 1-5
Approx 1 in 3 children
‘Episodic viral’ wheeze
Wheeze only with viral infections
No evidence for ICS
‘Multi-trigger’ wheeze
URTIs plus other triggers eg exercise, smoke, allergens
Only give oral prednisolone in subgroup of those requiring admission
See: Bush A, Grigg J, Saglani S. Managing wheeze in preschool children. BMJ 2014; 348

6. What is Asthma? A clinical diagnosis
There is no agreed definition, no known cause
Genetic susceptibility plus environmental trigger:
1st degree relative increases risk
Identical environments in siblings with and without asthma
Time course/“double hit” of atopic sensitization and viral infection eg hRV3; 1st year of life is crucial
There is no one test result that determines that you have asthma – it requires the health care professional to amalgamate signs and symptoms while excluding other possible diagnoses
All of the following have been suggested as risks for developing asthma:
Fetal exposure to maternal smoking
Viral respiratory infection in early life
Cleaner food and water
Traffic fumes
Genetics
Whether or not your maternal grandmother smoked (epigenetics)
Antibacterial cleaning products (Hygiene hypothesis)
Decreased exposure to animals

7. Clinical features that increase the probability of asthma
More than one of the following symptoms:
Wheeze, cough, DIB, chest tightness, particularly if symptoms:
are frequent and recurrent
are worse at night and in the early morning
occur in response to, or are worse after, exercise or other triggers, such as exposure to pets, cold, damp air, or with emotions/laughter
This is from the SIGN/BTS guideline
Sign post other resources (BMJ e learning, Articles, Recognition of a sick child/DIB modules)

8. Clinical features that increase the probability of asthma
Personal history of atopic disorder
Family history of atopic disorder and/or asthma
Widespread wheeze heard on auscultation
History of improvement in symptoms or lung function in response to adequate therapy

9. Clinical features that lower the probability of asthma
Symptoms with colds only, with no interval symptoms
Isolated cough in the absence of wheeze or difficulty breathing
History of moist cough
Prominent dizziness, light-headedness, peripheral tingling
Ask the audience to think of alternate diagnoses:
CF/bronchiectasis
Habitual cough
Anxiety/ hyper-ventilation
Gastro-oesophageal reflux
Inhaled foreign body

10. Clinical features that lower the probability of asthma
Repeatedly normal physical examination of chest when symptomatic
Normal peak expiratory flow (PEF) or spirometry when symptomatic
No response to a trial of asthma therapy
Clinical features pointing to alternative diagnosis

11. Airway pathology in asthma
The hallmark of asthma is chronic airway inflammation
This is the classic immune pathway by which an allergen inappropriately triggers inflammation in the airway. Inhaled allergen is sensed by an antigen presenting cell (macrophage or dendritic cell) which activates a Th2 cell. Via Th2 cytokines (IL-4, IL-5, IL-13) mast cells are stimulated to release histamine, and eosinophils release basic proteins. Both classes of cells release leukotrienes and prostaglandins, which act on blood vessels to increase blood supply tot he area, and recruit other immune cells, resulting in a positive feedback cycle of escalating inflammation.
It is not just allergens that can trigger this cycle – viruses are the commonest triggers, and may cause ‘runaway’ inflammation via Th1 and Th17 pathways as well. Air pollutants and cigarette smoke may also act via these pathways.
From: Bradding, P., Walls, A.F. & Holgate, S.T. (2006). The role of the mast cell in the pathophysiology of asthma.
J Allergy Clin Immunol 117, 1277–84

12. Airway pathology in asthma
This is the result of chronic inflammation – the airway appears like a chronic wound – think of it like a leg ulcer – hypertrophied, hyper-sensitive, mucousy

14. Signs and symptoms
The result of airway inflammation is airway narrowing
Airflow in a bronchus is like water flowing in a hose. If it is smooth there is lots of flow and no noise. If it is narrow there is less flow and the airflow is turbulent – this results in wheezing

16. Self management Avoid triggers Air pollution Passive (active) smoking
Aeroallergens when/if possible
Healthy diet
Studies in adults and children have shown that a high intake of fresh fruit and vegetables is associated with fewer asthma symptoms and better lung function
Triggers – extremely difficult to avoid
Almost impossible to remove all house dust mite – trigger unlikely to be dose dependent so deep cleaning/constant washing is not recommended
Laminar airflow systems show promise
Avoid busy roads/episodes of air pollution
Don’t get a pet if you are known to be sensitive (eg on skin prick test) (but don’t get rid of a pet if you already have one)

18. Self management Exercise Warm up and warm down
Use bronchodilator pre-exercise
Good evidence that exercise helps asthma
Complementary treatments
Buteyko breathing (a technique to control hyperventilation) has been shown to reduce symptoms
Encourage exercise – improves lung health
Signpost non-pharmacological therapies with an evidence base, as pts will seek them out

19. Pharmacotherapy Montelukast Steroids Monoclonal anti-IgE
(omalizumab, Xolair)
Preventers act on the immune system
Steroids act on the cell nucleus to decrease transcription of pro inflammatory genes
Montelukast is a leukotriene receptor antagonist
IgE is blocked by omalizumab
New monoclonals coming soon include anti IL-5 and anti IL-13
Lebrikizumab: anti IL-13
Mepolizumab: anti IL-5
Pascolizumab: anti IL-4

20. Management of chronic asthma
The aim of asthma care is complete control of symptoms on minimal therapy
Step up and step down decisions can be very difficult – some patients don’t want to step down due to fear of exacerbations, other don’t want to step up due to concerns about steroid side effects
What would the audience consider good control?
Rough guide is no exacerbation (time off school/work) for 6-12 mo and not needing to use salbutamol more than 1-2 puffs per week
Sign post BTS, BMJ e-learning, BMJ Dx and Mx of Asthma

21. For the under 5s – lower dose steroids, no LABA, early introduction of montelukast

22. Asthma control test During the past 4 weeks:
How often did your asthma prevent you from getting as much done at work, school or home?
How often have you had shortness of breath?
How often did your asthma (wheezing, coughing, chest tightness, shortness of breath) wake you up?
How often have you used your reliever inhaler?
How would you rate your asthma control ?
I would expect everyone here to be able to identify someone with poorly controlled asthma and refer them on appropriately.
Asthma control test is a useful tool.
Can be found on the asthma UK Web page – patients can take it for free – can do this before their follow-up appts with GP/practise nurse

23. Comorbidities Around 50% with asthma will have atopy
Eczema
Rhinitis
Hayfever
Antigen crossing via these sites can persistently sensitise the immune system
Important to optimise epithelial health
Barriers (emollient)
Immunomodulators (topical steroid)
Symptom control (antihistamines)

24. What’s in the pipeline Phenotyping asthma
Via SNPs eg leukotrienes and ALOX-5
“Urine dip” for asthma
By sputum leucocytes
By exhaled breath cytokine pattern (Th1, Th2, Th17)
Predicting exacerbations/inflammometry
FeNO (probably not in children)
Sputum eosinophil count (probably not in children)
ACT score
Peak flow fractals

25. Why phenotype? All that wheezes is not asthma
Consider the approach to management of other chronic inflammatory conditions in childhood
Joint arthropathies
Inflammatory bowel disease

27. Asthma Review: Checklist
The right diagnosis
Check symptom control (ACT)
Ask about and address smoking (child and parent)
The right treatment at the right time (step-wise)
Before initiating a new drug/step: check compliance with existing therapies, inhaler technique and try to eliminate trigger factors.
Minimise side effects from treatment (i.e. growth if on high dose ICS)
The right inhaler, correct technique
Give inhaler training, ensure correct technique before writing prescription
Referral pathways for smoking – find info to put in handout.
Side effects – STEROID CARD
SHINE – handout
Demonstrate competence before they leave with their new inhaler.

28. Asthma Review: Checklist
The gold standard is MDI + spacer
Give Asthma education
(repetition, reinforcement, signpost/give resources)
All children should have an Asthma Plan
Promote self-management
Compliance
Need regular review
Annual review
Review at hrs and 30 days post exacerbation/admission
Flu Jab
Step up and down
We will talk about asthma plans in the next talk

29. NICE Quality standards QS25
Statement 1. People with newly diagnosed asthma are diagnosed in accordance with BTS/SIGN guidance.
Statement 2. Adults with new onset asthma are assessed for occupational causes.
Statement 3. People with asthma receive a written personalised action plan.
Statement 4. People with asthma are given specific training and assessment in inhaler technique before starting any new inhaler treatment.
Statement 5. People with asthma receive a structured review at least annually.
Statement 6. People with asthma who present with respiratory symptoms receive an assessment of their asthma control.

30. NICE Quality Standards QS25
Statement 7. People with asthma who present with an exacerbation of their symptoms receive an objective measurement of severity at the time of presentation.
Statement 8. People aged 5 years or older presenting to a healthcare professional with a severe or life-threatening acute exacerbation of asthma receive oral or intravenous steroids within 1 hour of presentation.
Statement 9. People admitted to hospital with an acute exacerbation of asthma have a structured review by a member of a specialist respiratory team before discharge.
Statement 10. People who received treatment in hospital or through out-of-hours services for an acute exacerbation of asthma are followed up by their own GP practice within 2 working days of treatment.
Statement 11. People with difficult asthma are offered an assessment by a multidisciplinary difficult asthma service.

31. Useful learning resources
Acute breathing difficulties:
Spotting the Sick child;
Adult & Paed case studies:
Itchy Sneezy Wheezy:
Asthma UK
Summary slide is next – ask now if any questions

32. Further reading
BTS Guidelines 2011/12
Atopic Eczema in Children (NICE)
BNF for Children 2011/12
Nice guideline inhalers w

33. Questions
April 2010 33

34. Summary Asthma is very common Large disease burden
Morbidity & mortality
Regular asthma review
Assess control
Assess technique
Assess understanding, compliance/concordance
Question the diagnosis
Eg our 9yo with CF