Part B Insider (Multispecialty) Coding Alert

Hint: Identify symptoms and medication use for accurate reporting.

Asthma is a common condition that you may diagnose and treat at your Part B practice, so it’s vital to know the specifics of reporting this condition using ICD-10 codes before the Oct. 1, 2014 effective date.

Capture ICD-9 Codes Based on Etiology

When reporting a diagnosis of acute exacerbation of asthma using ICD-9 codes, you will have to focus on etiology of the condition to accurately report it. When you arrive at a diagnosis of acute exacerbation of asthma, you currently start with 493 (Asthma).

Depending on the causative factor for the asthma, 493 will expand into the following four codes:

• 493.0 (Extrinsic asthma) — You report this type when asthma is caused by allergens.
• 493.1 (Intrinsic asthma) — You report this type when asthma is induced after exercise or due to chemicals such as second-hand cigarette smoke, medications and cleaning agents
• 493.8 (Other specified asthma)
• 493.9 (Asthma unspecified)

The codes 493.0, 493.1 and 493.9 further expand using a fifth digit depending on the asthma state into unspecified, status asthmaticus and acute exacerbation.

For example, 493.0 expands into the following three codes:

• 493.00 — Extrinsic asthma unspecified
• 493.01 — Extrinsic asthma with status asthmaticus
• 493.02 — Extrinsic asthma with (acute) exacerbation

493.8 expands into these two codes:

• 493.81 — Exercise-induced bronchospasm
• 493.82 — Cough variant asthma

Base ICD-10 Reporting on Severity of the Condition

When ICD-10 codes come into effect in less than a year, the 493 series of codes under ICD-9 codes will crosswalk to J45 (Asthma). But, unlike ICD-9 codes, your ICD-10 coding is not centered over the etiology of the condition but follows the severity of the symptoms and the necessity for treatment with a nebulizer. This is consistent with the current national asthma treatment guidelines determined by The National Heart, Lung and Blood Institute.

Based on severity, you have the following four states of the condition (see chart for details):

• Mild intermittent
• Mild persistent
• Moderate Persistent
• Severe Persistent

When using ICD-10 codes, you will have to delve into the documentation to assess the severity of the condition as this is necessary for accurate reporting. J45 will further expand, based on severity, into the following five code sets as described in the guidelines:

• J45.2 (Mild intermittent asthma)
• J45.3 (Mild persistent asthma)
• J45.4 (Moderate persistent asthma)
• J45.5 (Severe persistent asthma)
• J45.9 (Other and unspecified asthma)

All these above mentioned codes further expand based on the asthma state into uncomplicated, acute exacerbation and status asthmaticus.

• For example, J45.2 expands into the following three subsets:
• J45.20 (Mild intermittent asthma, uncomplicated)
• J45.21 (Mild intermittent asthma with [acute] exacerbation)
• J45.22 (Mild intermittent asthma with status asthmaticus)
• J45.9 expands into the following code sets:
• J45.90 (Unspecified asthma) that further expands to J45.901, J45.902, J45.909

J45.99 (Other asthma) that further expands into J45.990 (Exercise-induced bronchospasm); J45.991 (Cough variant asthma) and J45.998 (Other asthma)

Example: You assess a patient with asthma who is currently experiencing episodes of acute exacerbation. You record a detailed history that reveals that the patient has been suffering from symptoms for more than two times a week. His use of the inhaler is also more than two times a week although he does not have to use it on a daily basis. The acute exacerbation of symptoms has been limiting his daily activities to a certain extent. You order some pulmonary function tests and record a forced expiratory volume in 1 second (FEV1) >80%. Based on the symptoms and results of tests, you can infer that the patient is suffering from acute exacerbation of a mild persistent type of asthma. You report the diagnosis using J45.31 (Mild persistent asthma with [acute] exacerbation).

Source: (National Heart, Lung, and Blood Institute. Expert Panel Report 3 (EPR3): Guidelines for the Diagnosis and Management of Asthma. URL: www.nhlbi.nih.gov/guidelines/asthma/asthgdln.htm).