Pathology/Lab Coding Alert

Question: Our lab prepares only routine stains for surgical pathology exams, and we are having problems billing for the special stains that we send out. For example, the pathologist may examine a bone marrow aspirate and prepare a cell block from the clot, which he also examines. If the pathologist wants a myeloperoxidase stain, he sends the cell block to a reference lab for staining. The lab returns the stained slides to our pathologist, who interprets them. The reference lab bills 88342-TC and 88323 for preparing and staining the slides. But we get denials when we report 88323 with 88305 for the cell block. How should we code this case?

Pennsylvania Subscriber Answer: The denials probably stem from a National Correct Coding Initiative edit that prohibits billing together 88305 and 88323. You can sometimes override this edit pair with modifier -59 (Distinct procedural service), but you should not in this case.

If your pathologist interprets the myeloperoxidase stains, which the reference lab only prepares but does not interpret and report, the reference lab should not bill you for 88323 (Consultation and report on referred material requiring preparation of slides). The reference lab should only report the special stain technical component as 88342 (Immunohistochemistry [including tissue immunoperoxidase], each antibody) with modifier -TC (Technical component).

You should report the case as follows for your pathologist's work:

Bone marrow aspiration - 85097 (Bone marrow, smear interpretation)
Cell block - 88305 (Level IV - Surgical pathology, gross and microscopic examination, cell block, any source)
Myeloperoxidase stain interpretation - 88342 with modifier -26 (Professional component).