Diagnosis of Asthma in Adults
Diagnosis based on recognition of a characteristic pattern of symptoms and signs and the absence of an alternative explanation. The key is to take a careful history
| High probability of asthma | Intermediate probability of asthma | Low probability of asthma |
| Start a trial of treatment | Investigate further | Investigate and manage accordingly |
| Review and assess response | Trial of treatment with careful observation and review | Reconsider diagnosis in those who fail to improve |
| Reserve further testing for those with poor response |
Lung function and reversibility testing | |
| Lung function tests should be used to establish the presence and severity of airflow obstruction. Spirometry* provides more information than peak expiratory flow (PEF). |
||
| Normal spirometry when the patient is assymptomatic does not exclude the diagnosis of asthma | ||
*Spirometry requires appropriately trained staff to undertake this investigation see http://dx.doi.org/10.4104/pcrj.2009.00054