Pulmonology Coding Alert

Question: What is the ICD-9 code for mild, intermittent asthma?

New Hampshire Subscriber

Answer: You will not find a specific code for mild, intermittent asthma.

Rather, asthma is broadly classified under 493.x with several subclassifications:

• 493.0x -- Extrinsic asthma
• 493.1x -- Intrinsic asthma
• 493.2x -- Chronic obstructive asthma
• 493.8x -- Other forms of asthma
• 493.9x -- Asthma, unspecified.

Codes 493.0x and 493.1x imply the existence of specific causes for the asthma. For example, extrinsic asthma is commonly due to allergic reactions and often occurs in children while intrinsic asthma commonly occurs in adults due to reasons other than allergies (for instance respiratory infections, chemical inhalation, smoking, etc.).

Code 493.2x implies a prolonged duration of the disease and 493.8x classifies the remaining types of asthma that are specified, meaning exercised-induced (493.81) and cough variants (493.82). Finally, 493.9x is for cases of asthma that are unspecified.

For the diagnosis of mild, intermittent asthma, this can be considered unspecified as you cannot discern the etiology (cause) nor the duration of the disease from the diagnosis. In this particular instance, you should use this code: 493. 92 (Asthma, unspecified; with [acute] exacerbation).

-- Clinical and coding expertise for this issue are provided by Carol Pohlig, BSN, RN, CPC, ACS, senior coding and education specialist at the University of Pennsylvania Department of Medicine in Philadelphia.