Pathology/Lab Coding Alert

Tip: Reserve 88384-88386 for ‘gene chips’ Simply counting probes won’t necessarily help you pick the right codes when your lab analyzes multiple nucleic acid markers.

You’ll need to know if the lab is using standard molecular diagnostics techniques or if it’s using a new array technology to characterize disease.

CPT Codes 2006 introduces three new codes for molecular probe arrays. If your lab uses one of the array platforms, you’ll need to learn how to use the following new codes:

• 88384--Array-based evaluation of multiple molecular probes; 11 through 50 probes
• 88385--… 51 through 250 probes
• 88386--… 251 through 500 probes. What Is an Array, Anyway? Arrays, commonly called “gene chips,” are devices that can hold many genetic probes in specific positions on a solid surface. “Array technology involves nucleic acid probes or DNA sequences imbedded in a platform such as a slide, chip or microbeads,” says Diana Voorhees, MA, CLS, MT(ASCP)SH, CLCP, principal with DV and Associates Inc. in Salt Lake City. “Microarrays” might pack thousands of probes on a tiny chip, but an array can also be tens of probes fixed on a slide.

By classifying large numbers of genes that may have altered expression patterns, arrays can aid in predicting biological behavior of certain cancers, for instance, and indicating susceptibility to treatment regimes. Method, Not Number, Determines Code Family Labs have used molecular diagnostic tests for years to analyze specific genetic or protein markers that aid in characterizing disease. A new CPT text note preceding 83890 specifies that “Codes 83890-83914 are intended for use with molecular diagnostic techniques for analysis of nucleic acids.”

Although arrays provide similar analysis, they allow for a much larger number of probes, and they are generally commercial products that a lab purchases and uses to analyze a given specimen. Another new CPT text note preceding 83890 states, “For array technology using more than 10 probes, see 88384-88386.”

If the lab uses standard molecular diagnostics techniques, you should report each step of the procedure using molecular diagnostics codes 83890-83914. For instance, you would list each probe using 83896 (Molecular diagnostics; nucleic acid probe, each). If the lab analyzes 44 specific nucleic acid probes, you should report 83896 x 44, plus 83912 (Molecular diagnostics; interpretation and report) for the interpretation.

Don’t miss: If the 44 probes are part of an array device that the lab purchases and uses, you should report 88384 for the test. You should document your code selection by stating that the lab used an array-based evaluation. Although arrays often involve large numbers of probes, the [...]