A modifier 24 can be utilized to pay for unrelated evaluation and management services during a global period. In the case of a transplant (such as liver or kidney), a special condition is carved out in modifier 24 guidelines that allow for billing of immunosuppressive therapy management during the 90-day postoperative period.
Outpatient office visits or inpatient visits for immunosuppressive therapy management by the same physician that performed the transplant can be unbundled and billed separately per CMS Claims Processing Manual Chapter 12 30.6.3. Documentation should indicate that the visit is for post-transplant immunosuppressive therapy to support the usage of the 24 modifier. While there is no specific guidance on diagnoses that will support coverage, a status code for an encounter following transplant (ex: Z48.22 Encounter for aftercare following kidney transplant) would likely be acceptable.