Pathology/Lab Coding Alert

Question: We had a liver biopsy Medicare case dated April 4, 2009, and the pathologist received a request on July 23 for an iron stain plus a PAS with and without diastase on the biopsy tissue. How should we code the special stains, and what should we use as the date of service if we're billing globally versus billing only the technical or professional component?

Arkansas Subscriber

Answer: Because the special stains your pathologist performed on the liver biopsy tissue are for "other" than microorganisms, the correct coding is three units of +88313 (Special stains [List separately in addition to code for primary service]; Group II, all other [e.g., iron, trichrome], except immunocytochemistry and immunoperoxidase stains, each).

In most cases, the DOS for the special stain technical component or global billing should be July 23. You can choose April 4 or July 23 as the DOS if you're only billing for the professional component.

Here's why: For Medicare patients, you need to follow CMS date of service (DOS) guidelines if you're billing for the technical component (TC) of pathology services. That means you'll need to follow the rule for TC or global billing, because the global service includes the TC.

The DOS guidelines state that for "archived specimens" -- those stored more than 30 days -- the DOS is the date you obtain the specimen from storage. In your example, the correct DOS would be July 23.

Problem: Because +88313 is an add-on code, Medicare typically denies the additional service without a primary procedure on the same day. Because the DOS guidelines require you to use the date of specimen collection for specimens that are not stored or archived, you'll have to report the initial biopsy DOS as April 4 (88307, Level V -- Surgical pathology, gross and microscopic examination, liver, biopsy -- needle/wedge).

What to do: In these cases, you can file a paper claim and provide a written explanation of the DOS discrepancy. If you don't provide an explanation up front, you might expect a claim denial that will require an appeal.

Do this for 26: Although pathology practices often opt to assign DOS consistently for global or professional component billing, you're not required to follow the CMS DOS policy when billing with modifier 26 (Professional component). If you're billing only for the special stain interpretation, you could use the April 4 DOS, although you'll need to determine if that falls outside of your payer time limit for filing a claim.