Drugs of abuse analysis: Proposed changes for 2010

Within the listing of 2010 HCPCS posted by CMS on November 2nd laboratorians will see two new G-codes that redefine coding of qualitative drug analysis billed to Medicare.

Qualitative test procedures provide a result of negative or positive and are not used to quantitatively measure the level in circulation. The initial qualitative analysis has historically been represented by two CPT codes that define various methodologies. In past years the code descriptions have received minor revisions to reflect their application to common methodologies of chromatography, enzyme assay and immunoassay.

Chromatography is a methodology by which drugs contained in a mixture are separated through a series of phases or procedures in order to simultaneously detect multiple drug classes. Rapid detection methods such as immunoassay and enzyme assay utilize an antigen-antibody reaction that can concurrently separate and identify the presence of individual drug classes. Test kits that provide reliable end-point or cut-off results in a matter of minutes (usually in less than 10 minutes) and the ability to visually read results or use cartridges that utilize table top “readers” has brought dependable screening procedures to the point of care in physician office settings and Emergency Departments as well as in the clinical laboratory. 

The methodologies discussed above are represented by the following CPT codes:

80100 - Drug screen, qualitative; multiple drug classes chromatographic method, each procedure

80101 - Drug screen, qualitative; single drug class method (e.g., immunoassay, enzyme assay), each drug class

In recent years, manufacturers have brought to market additional methods for qualitative analysis which do not fit into the current code descriptions of the AMA. The new HCPCS G0430 provides a coding option for the newer multi-drug kits and leaves CPT 80100 as a viable code in 2010 by excluding the chromatographic methodologies from the HCPCS assignment. The HCPCS G0431 appears to completely replace use of CPT 80101 for billing to the Medicare program. Care must be taken to ensure correct selection of CPT or HCPCS by matching the procedure methodology to the accurate code. Billing system updates for 2010 will need to account for reporting of the alternate HCPCS or the CPT based on payer requirements.

The new HCPCS codes are as follows:

G0430 -  DRUG SCREEN, QUALITATIVE; MULTIPLE DRUG CLASSES OTHER THAN CHROMATOGRAPHIC METHOD, EACH PROCEDURE

G0431 -  DRUG SCREEN, QUALITATIVE; SINGLE DRUG CLASS METHOD (E.G., IMMUNOASSAY, ENZYME ASSAY), EACH DRUG CLASS

The CPT codes 80102 for confirmation by qualitative analysis, and 80103 for preparation of tissue sample submitted for drug analysis, remain valid; however, the CPT code 80103, which is typically associated with postmortem or autopsy analysis is not separately paid by Medicare under the OPPS. Also, note that the AMA’s introductory guidance for drug testing states that confirmation will be accomplished by a second or different type of analytical methodology. Several methods of chromatography are available for qualitative confirmation of positive results including gas chromatograph(GC), thin layer chromatograph(TLC), high-pressure liquid chromatography (HPLC) and gas chromatograph mass spectrometry(GC/MS).  The use of GC/MS is the most widely accepted methodology for confirmation and is usually the methodology mandated by federal agencies.

In today’s society many drugs that are prescribed and dispensed for therapeutic treatment of acute and chronic disorders may later be determined to be a drug of abuse when the patient does not comply with prescribing instruction or when the drug is intentionally or accidentally ingested by someone other than the intended patient. The qualitative methods available on the market today offer a combination of illicit drugs and prescription drugs that are commonly linked to abuse, toxicity or overdose. Once a specific drug class is identified it may be necessary to perform additional testing to measure the drug level in circulation.

The CPT code series 80150 – 80202 provides a listing of frequently prescribed therapeutic drugs. The “not elsewhere specified” code – 80299 – should be considered for drugs that are classified as “therapeutic” but are not listed in this CPT series. The quantitative analysis for illicit drugs or drugs of abuse will most commonly be billed with CPT codes found in the listing of chemistry codes 82000-84999. Within this section of CPT the code will either describe the individual drug class (or its metabolite) or the methodology for analysis. 

Written by Robin Miller Zweifel, BS, MT (ASCP)