ED Coding and Reimbursement Alert

Question: If an Excludes1 note is listed after an ICD-10 code, does that mean you can never use the codes together, or are there exceptions?

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Answer: Over the course of the last several years, coders have been frustrated by the lack of guidelines about Excludes1 notes, but a recent article from the AHA’s Coding Clinic (Q4, 2018) offers some clarity on the topic.

Refresher:  The ICD-10-CM guidelines offer the following instructions regarding an Excludes1 note:

• “A type1 Excludes note is a pure excludes note. It means “not coded here.” An Excludes1 note indicates that the code excluded should never be used at the same time as the code above the Excludes1 note. An Excludes1 is used when two conditions cannot occur together, such as a congenital form versus an acquired form of the same condition.”

As you can see, these guidelines simply instruct you not to code any two given diagnoses at the same time. The classic conundrum that coders experience time and time again comes in their confusion about which code should they should report versus which they should omit. At last, the AHA Coding Clinic offers a definitive answer in the 2018 Q4 edition.

In the Coding Clinic Q&A, the reader asks for guidance in determining whether the main code listed in the tabular or the code referenced in the Excludes1 note should be reported. The Coding Clinic responds as follows:

• “Assign only the code referenced in the Excludes1 note.”

This means that, assuming one of the two diagnosis codes has an Excludes1 note beneath it, you should code according to the Excludes1 note instructions. Consider a scenario where the provider documents a patient with chronic obstructive pulmonary disease with acute lower respiratory infection and bronchiectasis. Since there are no diagnosis-relevant Excludes1 notes listed under J47- (Bronchiectasis), you will next have a look at the Excludes1 notes for J44- (Other chronic obstructive pulmonary disease). Here you see, among other Excludes1 notes, that the following note is listed:

• “Bronchiectasis (J47.-).”

Based on the new Coding Clinic guidelines, you should report the code listed in the J44- Excludes1 note, J47.-. Specifically, you will report J47.9 (Bronchiectasis, uncomplicated). However, consider a scenario in which both diagnosis codes offer an Excludes1 note advising to use the other respective diagnosis code. Unfortunately, the Coding Clinic does not offer guidance on how you should address this particular scenario.

However, inferring from the above guidelines, the Coding Clinic would presumably allow for the coder to choose between either coding option. Ideally, if one diagnosis code is distinctively primary over another, you should report the primary coding option and disregard the secondary. Until the AHA offers further advice on the subject, coders should consider the Coding Clinic guidance when reviewing paired Excludes1 notes, but ultimately use their own judgment on which code best supports the documented diagnosis

In the same quarterly issue, the Coding Clinic addresses one final situation involving the use of the Excludes1 parenthetical notation. In this reader question, the reader inquiries about the coding of nutritional anemia and anemia. In this example, D53.9 (Nutritional anemia, unspecified) has an Excludes1 note instructing the coder to code D64.9 (Anemia, unspecified) when the provider also documents “anemia NOS.”

The Coding Clinic advises that, in this example, it would be inappropriate to follow by the Excludes1 guidelines and report only D64.9. That’s because, as the Coding Clinic puts it, “it would be contradictory to have a code for unspecified and another specified code for the same condition.” Even though this kind of example might be rare, it’s important to keep your thinking cap on when addressing diagnosis codes that involve Excludes1 notes. While this Excludes1 note appears to be an error on the part of the ICD-10-CM, the 2019 manual does not address the issue.

However, it offers a valuable lesson that the general principles of coding should always be followed over parenthetical notes such as an Excludes1 note. In this case, do not code the same condition twice, even if the ICD-10 instructs you to do so in the parenthetical notes.