British guideline on the management of asthma in children

The British Thoracic Society & Scottish Intercollegiate Guidelines Network

SIGN: Edinburgh, 2008 (revised 2009)

Diagnosis

Focus the initial assessment in children suspected of having asthma on:
- the presence of key features in history and examination
- careful consideration of alternative diagnoses
Clinical features that increase the probability of asthma:
- more than one of the following symptoms: wheeze, cough, difficulty breathing, chest tightness, particularly if these 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 or damp air, or with emotions or laughter, or occur apart from colds
- 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
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
- repeatedly normal physical examination of chest when symptomatic
- no response to a trial of asthma therapy
- clinical features pointing to alternative diagnosis
With a thorough history and examination, a child can usually be classed into one of three groups:
- high probability—diagnosis of asthma likely
- low probability—diagnosis other than asthma likely
- intermediate probability—diagnosis uncertain
Record the basis on which a diagnosis of asthma is suspected
In children with a high probability of asthma:
- start a trial of treatment
- review and assess response
- reserve further testing for those with a poor response
In children with a low probability of asthma consider more detailed investigation and specialist referral
In children with an intermediate probability of asthma who can perform spirometry and have evidence of airways obstruction, assess the change in FEV1 or PEF in response to an inhaled bronchodilator (reversibility) and/or the response to a trial of treatment for a specified period:

if there is significant reversibility, or if a treatment trial is beneficial, a diagnosis of asthma is probable. Continue to treat as asthma, but aim to find the minimum effective dose of therapy. At a later point, consider a trial of reduction, or withdrawal, of treatment
if there is no significant reversibility, and treatment trial is not beneficial, consider tests for alternative conditions

In children with an intermediate probability of asthma who cannot perform spirometry, offer a trial of treatment for a specified period:
- if treatment is beneficial, treat as asthma and arrange a review
- if treatment is not beneficial, stop asthma treatment, and consider tests for alternative conditions and specialist referral
In children with an intermediate probability of asthma who can perform spirometry and have no evidence of airways obstruction:
- consider testing for atopic status, bronchodilator reversibility and if possible, bronchial hyper-responsiveness using methacholine, exercise, or mannitol
- consider specialist referral
In some children, particularly those under the age of 5 years, there is insufficient evidence for a firm diagnosis of asthma but no features to suggest an alternative diagnosis. Possible approaches (dependent on frequency and severity of symptoms) include:
- watchful waiting with review
- trial of treatment with review
- spirometry and reversibility testing

Remember: the diagnosis of asthma in children is a clinical one. It is based on recognising a characteristic pattern or episodic symptoms in the absence of an alternative explanation