Pathology/Lab Coding Alert

Find out why Medicare denies your second slide consult.

The once-secret limit to the number of units Medicare will cover for a given lab procedure is out of the shadows -- mostly.

Despite the agency's insistence that it would not make public the medically-unlikely edits (MUEs), CMS changed course and published the list on Oct. 1.

Caveat: The list of MUEs on the CMS Web site is not entirely complete. The published list "will consist of most of the codes with MUE values of 1-3, - [but not] MUE values that are 4 or higher because of CMS concerns about fraud and abuse,"

according to Kimberly Brandt, CMS Director, Program Integrity Group, in an open MUE publication announcement letter.

Brandt continues, "A minimal number of MUEs with lower values that are believed by CMS to be particularly vulnerable to fraud and abuse may not be published."

Take-home lesson: If a code isn't on the MUE list, that doesn't mean it is not subject to an MUE limit.

Although CMS proposed limits to certain surgical pathology codes in the past, such as 88305 (Level IV - Surgical pathology, gross and microscopic examination) and 88307 (Level V - Surgical pathology, gross and microscopic examination),neither of the codes are on the published MUE list.

Beware WPS experience: Earlier this year, however, Wisconsin Physicians Service (WPS) began denying 88305 and 88307 claims with more than one unit, according to Stan Werner, MT (ASCP), administrative director of Peterson Laboratory Services, PA, in Manhattan, Kan. "Although the intermediary stated that the denials were due to an MUE limit of one for the codes, we were told to bill each as a separate line item with modifier 76 (Repeat procedure by same physician) if we could show medical necessity for the multiple units," Werner says.

All's well that ends well: "WPS eventually discontinued the edit, and we-re not receiving the denials at this time," Werner says.

We hope -: The WPS experience has left questions about whether 88305 and 88307 might be part of the "unpublished" MUEs -- and that has pathologists concerned.

Here's why: Multiple units of 88305 are often medically necessary, such as when pathologists examine multiple distinct skin or prostate biopsies and correctly report several units of 88305 on the same day.

The MUE program aims to help CMS "dramatically reduce costly payment errors," said CMS Acting Administrator Kerry Weems in an Oct. 1 statement. However, the news release acknowledges that "CMS has not yet determined if there have been any savings in the MUE program since it was implemented" in January of 2007.

The MUE list differs from standard Correct Coding Initiative (CCI) edits in that it does not include code pairs. Instead, it lists specific CPT or HCPCS codes, followed by the number of units that CMS will pay. For example, the MUEs allow you to report only one unit of 81007 (Urinalysis; bacteriuria screen, except by culture or dipstick). You can, however, report two units of 81005 (Urinalysis; qualitative or semiquantitative, except immunoassays).

What to expect: The MUE list restricts over 800 lab codes to one, two, or three units of service. Types of testing subject to the unit-edits include drug tests, urinalysis, chemistry assays, immunology, hematology, Pap smears, and consultations, among others.

The following is a sampling of lab codes that allow you to bill one, two, or three units to Medicare:

Indicator of 1: You can report just one unit of the following codes before the MUEs kick in:

- 88321 -- Consultation and report on referred slides prepared elsewhere

- 88323 -- Consultation and report on referred material requiring preparation of slides

- 88325 -- Consultation, comprehensive, with review of records and specimens, with report on referred material.

These are particularly problematic MUEs. Based on CPT guidelines and historical Medicare payment policy, pathologists have always billed these codes "per case." In fact, an example from a Medicare carrier describes a referral for consultation involving a skin biopsy from 1997 and a skin biopsy from 2001 and concludes: "these are two surgical pathology cases - and can be signed out as two units of 88321."

Indicator of 2: You can report two units of most hematology and coagulation procedures before the MUEs kick in, such as the following three codes:

- 85210 -- Clotting; factor II, prothrombin, specific

- 85300 -- Clotting inhibitors or anticoagulants; antithrombin III, activity

- 85378 -- Fibrin degradation products, D-dimer; qualitative or semiquantitative.

Indicator of 3: You can report three units of the following chemistry codes before the MUEs kick in:

- 82308 -- Calcitonin

- 82355 -- Calculus; qualitative analysis

- 82374 -- Carbon dioxide (bicarbonate).

Caution: CMS is concerned that providers will incorrectly interpret MUE values as utilization guidelines, according to Brandt. "MUE values do NOT represent units of service that may be reported without concern about medical review. Providers should continue to only report services that are medically reasonable and necessary," she says.

Look for quarterly updates: CMS will update the MUE values on its Web site on a quarterly basis. Future postings of MUE values will also include some codes with MUE values of 4 or more.

To read the complete list of MUEs or to find out more about the MUE program, go online to the CMS Web site at http://www.cms.hhs.gov/NationalCorrectCodInitEd/08_MUE.asp#TopOfPage.

What should you do if you can show medical necessity for multiple units of a single procedure that exceeds an MUE edit?

As of Jan. 1, 2008, Medicare provides a HCPCS Level II modifier, presumably for use in instances when the medically necessary units-of-service for a particular procedure code exceeds MUEs: GD (Units of service exceed medically unlikely edit [MUE] value and represent reasonable and necessary services).

Questions remain: CMS has not published any instructions about using this modifier. In fact, Medicare's current "Frequently Asked Questions" about medically unlikely edits still suggests listing multiple procedures on separate lines and using an appropriate modifier such as 91 (Repeat clinical diagnostic laboratory test) or 59 (Distinct procedural service).

Caution: The National Correct Coding Initiative Policy Manual states that occurrences when you need to override an MUE edit should be "uncommon," and you may be coding incorrectly if you override the edits frequently.You may want to contact your carrier for further direction before you begin using modifier GD.