Pathology/Lab Coding Alert

Question: When we use an immunohistochemistry stain to identify Melan-A positive melanocytes to diagnose melanoma, the target cells are difficult to distinguish from melanin. We-ve started to stain the slides with Giemsa as well because it stains the melanin green, which helps us distinguish the brown Melan-A positive melanocytes. Can we report both the immunohistochemistry and Giemsa stains?

Ohio Subscriber

Answer: The charge for the service you describe should be 88342 (Immunohistochemistry [including tissue immunoperoxidase], each antibody) for the Melan-A immunohistochemistry (IHC) stain.

You should not charge an additional +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) for the Giemsa.

Here's why: In this case, you-re using the Giemsa as a counterstain, which is not separately billable. The pathologist does not provide a distinct interpretation for the results of the Giemsa stain. Rather, the Giemsa stain simply helps eliminate "background" cells so that the pathologist can interpret the cells of interest -- IHC stained melanocytes. In other words, the Giemsa doesn't provide separate diagnostic information; it simply allows the Melan-A stain to work better.