Treatment of Congenital Athymia

This policy covers implantation of allogeneic processed thymus tissue (agdc) for treatment of congenital athymia in pediatric patients. Coverage is limited to individuals ≤21 years with confirmed congenital athymia by flow cytometry (e.g., <50 naïve T cells/mm³ or <5% naïve T cells) with SCID excluded and requires meeting all specified criteria — including no prior thymus implantation, adequate infection‑control measures and immunoglobulin replacement, anti‑HLA antibody screening and donor HLA compatibility, exclusion of high‑risk comorbidities, manufacturer‑adjusted dosing and single surgical administration, and use of peri‑procedural immunosuppression when indicated — with benefit plan and state rules (e.g., Illinois statute) potentially further limiting coverage.

"Therapy is covered when proven effective for the relevant diagnosis or procedure based on generally accepted standards of practice."