Radiology Coding Alert

Use this expert guidance to make sense of this plethora of new and revised guidelines.

As a coder, you are taught early on that putting your skills to practice begins and ends with a strong understanding of the guidelines. What some coders fail to recognize, though, is that the guidelines are not a finite entity. That is — they are subject to change on, at the very least, an annual basis.

If you’re safe from any changes via CPT^® Assistant or Coding Clinic articles, you’ve still got to be aware of the annual amendments to the ICD-10-CM guidelines. As you’ll see, these changes can come in a variety of formats — and we’ve outlined some that will certainly have an impact on your coding specialty.

Have a look at this next round of ICD-10-CM guideline changes to keep yourself fully prepared for whatever coding scenarios happen to come your way.

Distinguish Between Codes for Hx of Primary, Secondary Malignancy

In the past, you may have struggled to report the proper code for a patient’s history of primary and secondary malignancies. In Chapter 2 of Section 1.C of the 2019 ICD-10-CM guidelines, ICD-10-CM incorporates an extra note explaining which codes you should use depending on whether the provider documents the history of malignancy as primary or secondary:

• “When a primary malignancy has been previously excised or eradicated from its site, there is no further treatment (of the malignancy) directed to that site, and there is no evidence of any existing primary malignancy at that site, a code from category Z85, Personal history of malignant neoplasm, should be used to indicate the former site of the malignancy.
  Subcategories Z85.0 – Z85.7 should only be assigned for the former site of a primary malignancy, not the site of a secondary malignancy. Codes from subcategory Z85.8-, may be assigned for the former site(s) of either a primary or secondary malignancy included in this subcategory.”

As you can see, you’ve now got a clear-cut set of instructions to utilize depending on the whether the patient’s history of malignancy is primary or secondary. For instance, if the patient has a history of a primary lung malignancy, you will report code Z85.118 (Personal history of other malignant neoplasm of bronchus and lung). However, if the patient has a history of secondary lung malignancy, you will report code Z85.89 (Personal history of malignant neoplasm of other organs and systems) for lack of a more specific option. If the provider does not specify primary versus secondary malignancy, you should query the provider for further documentation.

Coder’s note: “It’s always best to query if you can’t determine primary versus secondary,” advises Lindsay Della Vella, COC, medical coding auditor at Precision Healthcare Management in Media, Pennsylvania. “With diagnoses like cancer and stroke, among other major diseases, a coding error can cause a plethora of unintended problems for the practice, as well as the patient,” Della Vella cautions.

As Della Vella describes, coding scenarios involving history of malignancy can be tricky due to the lack of proper documentation. And, while one of the golden rules of coding is to “never assume,” you should feel comfortable making an exception in certain situations. For example, if the provider documents a “history of lung cancer,” you may report the lung cancer as primary unless further documentation specifies otherwise. However, if the provider documents “history of lung and bone cancer,” it would be in your best interest to query the provider to determine whether one, or both, of the diagnoses were primary malignancies.

Semantics Matters When It Comes to CKD Coding

Next, you’ll find two subtle, but important revisions to the hypertension and hypertensive chronic kidney disease (CKD) guidelines in Chapter 9 of Section 1.C. First note this revision to the guidelines on hypertension coding:

• “The same heart conditions (I50.-, I51.4-I51.7, I51.89, I51.9) with hypertension are coded separately if the provider has specifically documented a different cause they are unrelated to the hypertension. Sequence according to the circumstances of the admission/encounter.”

First, you’ll want to consider the changes to the I51 (Complications and ill-defined descriptions of heart disease) code set. The codes in bold represent the new ICD-10-CM codes implemented on October 1, 2018. Following this newly revised guideline, you’ll want to consider the association between a patient’s heart conditions and hypertension diagnoses before reporting a specific code. As long as the provider details that the two conditions are unrelated to one another, you may report the heart condition and hypertension diagnoses separately. Next, have a look at this guideline on hypertensive CKD coding:

• “Assign codes from category I12, Hypertensive chronic kidney disease, when both hypertension and a condition classifiable to category N18, Chronic kidney disease (CKD), are present. CKD should not be coded as hypertensive if the physician has specifically documented a different cause provider indicates the CKD is not related to the hypertension.”

Prior to the new guidelines, ICD-10-CM required providers to outline an entirely separate cause in order for you to report a patient’s CKD and hypertension separately. Now, the provider only needs to identify that the CKD is not related to the hypertension in order for the coder to feel comfortable coding the CKD as non-hypertensive.

Report Separate Codes for Different Subsequent MI Type

Here’s another brand-new guideline that’s sure to have an impact on numerous specialties. As of October 1, 2018, ICD-10-CM requires you to report codes from two separate categories if a patient’s subsequent myocardial infarction (MI) differs in type from the initial MI:

• If a subsequent myocardial infarction of one type occurs within 4 weeks of a myocardial infarction of a different type, assign the appropriate codes from category I21 to identify each type. Do not assign a code from I22. Codes from category I22 should only be assigned if both the initial and subsequent myocardial infarctions are type 1 or unspecified.

There are a few points to unpack here. First, this guideline only pertains to acute subsequent MIs that occur within a four-week time period from the initial MI. In those instances, assuming the subsequent MI differs in type from the initial, you will report the respective codes from category I21 (Acute myocardial infarction). If the provider documents each MI as either type 1 or unspecified, you will report the subsequent MI under category code I22 (Subsequent ST elevation (STEMI) and non-ST elevation (NSTEMI) myocardial infarction) and the initial under category code I21.

Refresher: Before adopting these new MI guidelines into practice, make sure you know how to distinguish between the varying types of MIs. “Type 1 MIs occur when there is an acute event that blocks oxygenating blood — embolism, rupture, thrombosis),” details Sheri Poe Bernard, CPC, of Poe Bernard Consulting in Salt Lake City, Utah. “Types 2-5, on the other hand, occur when there is not enough oxygenation of heart tissues for other reasons — COPD [chronic obstructive pulmonary disease], tachycardia, shock,” Bernard explains.