Pathology/Lab Coding Alert

Unit of service is payment key.

One new code gives labs a way to report drug screens by multiple drug class methods that aren't chromatographic -- a gap that labs couldn't account for in the past.

That's only true if you're not billing Medicare. Last month you learned how to bill drug screens to Medicare payers in "G0431, G0434 Encompass Medicare Drug Screens" (Vol. 12, No. 3 of Pathology/Lab Coding Alert). This month we'll show you how to maneuver just three CPT codes to get paid for your lab's drug screening tests for payers other than Medicare.

'Method' Leads Your Choice

You'll find two existing codes and one new code for drug screenings in CPT 2011, as follows:

• 80100 -- Drug screen, qualitative; multiple drug classes chromatographic method, each procedure
• 80101 -- ... single drug class method (e.g., immunoassay, enzyme assay), each drug class
• 80104 (new) --... multiple drug classes other than chromatographic method, each procedure.

You should choose between these codes based on the lab method, such as chromatography or immunoassay, as well as whether the test uses single or multiple procedures to identify multiple drug classes.

General distinction: Use 80100 for complex chromatographic instruments and 80101 for complex chemistry analyzers that involve distinct analysis per drug class. Reserve new code 80104 for multiplexed methods that identify multiple drug classes, such as drug test kits.

These are typically less complex, involving tests that waived status labs (under the Clinical Laboratory Improvement Amendments " CLIA) might perform.

Payer surprise: "We've checked with our biggest commercial payers, and they're not accepting 80104," says Bobbi Andera, BSMT, AMT, business/regulatory manager for Sanford Laboratories in Sioux Falls, S.D. "Instead, we're instructed to use either 80100 or 80101," she says.

Watch Units of Service

The unit of service is different for codes 80100-80104. You'll need to understand the units to ensure that you don't under or over charge for your lab's services.

80100 per procedure: If your lab uses a chromatography instrument that identifies one or more drugs or drug classes as the specimen passes through the chromatography column, you may be able to report multiple units of 80100, in some circumstances. CPT's definition of "each procedure" for chromatography procedures refers to a single mobile and stationary phase, regardless of the number of analytes (drugs or drug classes) that you test. If your test involves multiple mobile/stationary phases, you can report multiple units of 80100.

Beware test kit trap: Some drug screen test kits have descriptions such as "immunochromatographic method," but that doesn't mean you should report 80100. "A true chromatographic procedure that you should report as 80100 uses a large expensivechromatography instrument that will identify one or more drugs as the specimen passes through the chromatography device," explains William Dettwyler, MT AMT, president of Codus Medicus, a laboratory coding consulting firm in Salem, Ore.

80101 per drug class: If your lab screens for drugs using instrumentation that involves "single drug class method," such as a laboratory analyzer using immunoassay technique, you can report 80101 once per drug class. "Make sure you don't use this code for drug test kits that evaluate multiple drug classes in a single procedure," cautions Robin Miller Zweifel, MT (ASCP), a laboratory coding and billing compliance consultant in Niota, Tenn.

80104 per procedure: CPT 2011 adds a text note for this new code stating, "For qualitative analysis by multiplexed screening kit for multiple drugs or drug classes, use 80104." That means if your lab uses one of the test kits or point-of-care analyzers that screen for multiple drugs or drug classes in a single procedure, you should only report one unit of 80104 -- you should not code once per drug class.

It appears that Medicare won't accept 80100-80104 for drug screening. Instead, you should report one of the following two codes for drug screens, based on the test complexity:

• G0431 (revised) -- Drug screen, qualitative; multiple drug classes by high complexity test method (e.g., immunoassay, enzyme assay), per patient encounter
• G0434 (new) -- Drug screen, other than chromatographic; any number of drug classes, by CLIA waived test or moderate complexity test, per patient encounter.

Because the units of service are different, you might expect different pay from Medicare and other payers for the same drug test.

For instance: If your lab uses a high complexity lab analyzer using immunoassay methodology to screen for 10 drug classes, Medicare would pay $102.33 for G0431 (Drug screen, qualitative; multiple drug classes by high complexity test method [e.g., immunoassay, enzyme assay], per patient encounter). Assuming a single drugclass rate of $20.47 (CMS's assumption), you might expect a non-Medicare payer to reimburse $204.70 for the same analysis.

That's not all: "There is not a direct one to one mapping between 80101 and G0431," Zweifel says. "You'll need to carefully read your instrumentation and test kit instructions to determine the appropriate HCPCS Level II or CPT codes."