Diagnosis in Adults

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Summary of practice points Level of evidence
Wheeze suggests asthma but is not pathognomonic. [√]
The absence of physical signs does not exclude a diagnosis of asthma. [√]
Look for signs of allergic rhinitis in patients with suspected asthma. [√]
Do not rely on peak flow meters for assessing airflow limitation in the diagnosis of asthma. [√]
Spirometry is the lung function test of choice for diagnosing asthma and for assessing asthma control in response to treatment. [√]
Pay close attention to spirometry technique to ensure you get the most reliable readings. [√]
The absence of acute reversibility of airflow limitation in response to a short-acting bronchodilator does not exclude the diagnosis of asthma.  [√]
Chest X-ray should be ordered if the diagnosis is uncertain, if there are symptoms not explained by asthma, and to exclude other conditions. [√]
Challenge tests may help confirm a diagnosis of asthma. These should be performed only in specialist facilities. [√]
Consider allergy testing whenever you diagnose asthma.  [√]
Consider referral to a specialist respiratory physician when the diagnosis is uncertain and for patients in whom occupational asthma is suspected. [√]
Assess the severity of underlying asthma at the initial visit in a patient with newly diagnosed asthma, then reassess severity classification and/or asthma control at subsequent reviews.   [√]

*Note: There is no ‘gold standard’ for the diagnosis of asthma.