You are here

Asthma H002

Last amended 
15 November 2016
Current RMA Instruments
Reasonable Hypothesis SOP60 of 2012
Balance of Probabilities SOP 61 of 2012
Changes from previous instruments

SOP Bulletin 161

 ICD Coding
  • ICD-9-CM Codes: 493
  • ICD-10-AM Codes: J45, J46
Brief description

Asthma is a common chronic respiratory condition with variable recurring symptoms, variable airflow obstruction, bronchial hyperresponsiveness and an underlying inflammation.  The SOP also covers reactive airways dysfunction syndrome, which is a specific asthma-like condition that can arise following intense exposure to certain irritants.

Confirming the diagnosis

The diagnosis of asthma requires respiratory symptoms consistent with asthma (intermittent shortness of breath, chest tightness, cough, and wheezing), together with demonstrated variable, reversible expiratory airflow obstruction on spirometry.  Asthma can be difficult to distinguish from other inflammatory disorders of the airways, particularly (smoking-related) chronic obstructive pulmonary disease.

For a diagnosis of reactive airways dysfunction syndrome the specific criteria detailed in the SOP need to be met.

The relevant medical specialist is a respiratory physician.

Additional diagnoses covered by SOP
  • Chronic airflow limitation due to asthma
  • Chronic obstructive airways disease due to asthma
  • Reactive airways dysfunction syndrome
Conditions excluded from SOP
  • Bronchiectasis*
  • Bronchiolitis obliterans organising pneumonia*
  • Cardiac asthma (due to heart failure - code to underlying cause)
  • Chronic cough – insufficient for a diagnosis
  • Chronic obstructive pulmonary disease* (as defined in that SOP)
  • Extrinsic allergic alveolitis*
  • Fibrosing alveolitis* - fibrosing interstitial lung disease

* another SOP applies

Clinical onset

Asthma may develop at any age, but onset is before age seven in around 75% of cases.  There is often a remission in symptoms in adolesence with recurrence later in life.  The symptoms of asthma are non-specific, but medical attention is likely to have been sought very soon after relevant symptoms commenced.

Clinical worsening

Asthma is one of the very few SOPs that include a definition of clinical worsening.  The requirements of that definition must be fulfilled before clinical worsening can be considered.