Otolaryngology Coding Alert

Question: Do we need a fifth digit when reporting an asthma diagnosis, such as 493.2?


North Carolina Subscriber
Answer: You should always report a diagnosis to the highest-possible level of specificity. Therefore, if ICD-9 makes a fifth digit available, you should include it.
 
ICD-9 contains four main categories to describe asthma diagnoses:

- 493.0x--Extrinsic asthma

- 493.1x--Intrinsic asthma

- 493.2x--Chronic obstructive asthma

- 493.9x--Asthma, unspecified.
 
The fifth digit identifies the asthma's current state:

- 0--unspecified

- 1--with status asthmaticus

- 2--with (acute) exacerbation. For patients who do not have status asthmaticus or acute exacerbation, use a fifth digit of -0.- Code 493.x0 is appropriate when the patient presents for a checkup and his asthma is controlled.

A final digit of -1- indicates that the patient has status asthmaticus, which is a medical emergency and usually treated in the emergency department.

You should assign a -2- for patients who present with asthma that is now exacerbated (in other words, something has caused the condition to flare up).

Why it matters: Without this higher level of specificity, the payer may deny your claim for lack of medical necessity.

Example: For instance, an asthma patient has an acute exacerbation that requires a nebulizer treatment (94640, Pressurized or nonpressurized inhalation treatment for acute airway obstruction or for sputum induction for diagnostic purposes [e.g., with an aerosol generator, nebulizer, metered dose inhaler or intermittent positive pressure breathing (IPPB) device]).

In this case, you should link 94640 to 493.x2. Reporting a 2 as the fifth digit helps the payer to understand why the patient needs the treatment. Without the final digit (or a fifth digit of 0), the payer may assume that the patient's asthma is under control, making the coded treatment unnecessary.