How to use XE,XS,XP AND XU modifier with 59 Modifier – Update from Medicare

The Medicare National Correct Coding Initiative (NCCI) has Procedure to Procedure (PTP) edits to prevent unbundling of services, and the consequent overpayment to physicians and outpatient facilities. The underlying principle is that the second code defines a subset of the work of the first code. Reporting the codes separately is inappropriate. Separate reporting would trigger a separate payment and would constitute double billing.

CR8863discusses changes to HCPCS modifier -59, a modifier which is used to define a “Distinct Procedural Service.” Modifier -59 indicates that a code represents a service that is separate and distinct from another service with which it would usually be considered to be bundled.

The -59 modifier is the most widely used HCPCS modifier. Modifier -59 can be broadly applied. Some providers incorrectly consider it to be the “modifier to use to bypass (NCCI).” This modifier is associated with considerable abuse and high levels of manual audit activity; leading to reviews, appeals and even civil fraud and abuse cases.

The primary issue associated with the -59 modifier is that it is defined for use in a wide variety of circumstances, such as to identify:

*** Different encounters;
*** Different anatomic sites; and
*** Distinct services.

The -59 modifier is


*** Infrequently (and usually correctly) used to identify a separate encounter;
*** Less commonly (and less correctly) used to define a separate anatomic site; and
*** More commonly (and frequently incorrectly) used to define a distinct service.

The -59 modifier often overrides the edit in the exact circumstance for which CMS created it in the first place. CMS believes that more precise coding options coupled with increased education and selective editing is needed to reduce the errors associated with this over payment.

CR8863 provides that CMS is establishing the following four new HCPCS modifiers (referred to collectively as -X{EPSU} modifiers) to define specific subsets of the -59 modifier:

*** XE Separate Encounter, A Service That Is Distinct Because It Occurred During A Separate Encounter,

*** XS Separate Structure, A Service That Is Distinct Because It Was Performed On A Separate Organ/Structure,

*** XP Separate Practitioner, A Service That Is Distinct Because It Was Performed By A Different Practitioner, and

*** XU Unusual Non-Overlapping Service, The Use Of A Service That Is Distinct  Because It Does Not Overlap Usual Components Of The Main Service.

CMS will continue to recognize the -59 modifier, but notes that Current Procedural Terminology (CPT) instructions state that the -59 modifier should not be used when a more descriptive modifier is available. While CMS will continue to recognize the -59 modifier in many instances, it may selectively require a more specific – X{EPSU} modifier for billing certain codes at high risk for incorrect billing. For example, a particular NCCI PTP code pair may be identified as payable only with the -XE separate encounter modifier but not the -59 or other -X{EPSU} modifiers. The -X{EPSU} modifiers are more selective versions of the -59 modifier so it would be incorrect to include both modifiers on the same line.

The combination of alternative specific modifiers with a general less specific modifier creates additional discrimination in both reporting and editing. As a default, at this time CMS will initially accept either a -59 modifier or a more selective – X{EPSU} modifier as correct coding, although the rapid migration of providers to the more selective modifiers is encouraged.

However, please note that these modifiers are valid even before national edits are in place. MACs are not prohibited from requiring the use of selective modifiers in lieu of the general -59 modifier, when necessitated by local program integrity and compliance needs.

Relationship of Modifiers XE, XP, XS, and XU to Modifier 59

“These modifiers, collectively referred to as -X{EPSU} modifiers, define specific subsets of the -59 modifier…The -X{EPSU} modifiers are more selective versions of the -59 modifier so it would be incorrect to include both modifiers on the same line.”

“Only if no more descriptive modifier is available, and the use of modifier 59 best explains the circumstances, should modifier 59 be used.”

Reimbursement Guidelines

Effective for dates of service January 1, 2015 and following, Moda Health will accept modifiers XE, XS, XP, and XU and will expect providers to use modifiers XE, XS, XP, and XU in place of modifier 59 when appropriate.

* Modifier 59 should not be used when one of the -X{EPSU} modifiers describes the reason for the distinct procedural service. The -X{EPSU} modifiers are more specific versions of the -59 modifier.

* It is not appropriate to bill both modifier 59 and a -X{EPSU} modifier on the same line.  CPT codes submitted with modifiers XE, XP, XS, XU, or 59 appended will be considered separately reimbursable when all of the following apply:

* The clinical edit is eligible for a modifier bypass (e.g. per edit rationale, CCI modifier indicator = “1”, etc.).

* CMS policy on the -X{EPSU} modifiers is evolving. If CMS indicates a specific edit may only be bypassed with a specific -X{EPSU} modifier but is not eligible for a bypass with the other -X{EPSU} modifier options or with modifier 59, Moda Health will follow those specific requirement as well.

“For example, a particular NCCI PTP code pair may be identified as payable only with the -XE separate encounter modifier but not the -59 or other -X{EPSU} modifiers.”

* The CPT code is not considered a bundled component of a more comprehensive procedure (code definitions, standards of medical & surgical practice, etc.).

* The modifier and the code have been submitted in accordance with AMA CPT book guidelines, CPT Assistant guidelines, CMS/NCCI Policy Manual guidelines, and any applicable specialty society guidelines.

* The medical records documentation supports the appropriate use of modifiers XE, XP, XS, XU, or 59.

*  The procedure code is eligible for separate reimbursement according to the status indicators on the CMS fee schedule for the relevant provider type (physician fee schedule, ASC, OPPS, etc.).