Long-term remission of HSCT-related NS after a second allogenic stem cell transplant.

BACKGROUND: Hematopoietic stem cell transplantation (HSCT)-related nephrotic syndrome (NS) is a rare event and has been described as a clinical form of chronic graft-versus-host disease (GVHD). Although immunological mechanisms are thought to play important roles in NS after HSCT, the exact mechanisms have not been clarified.

CASE-DIAGNOSIS/TREATMENT: We report a 4-year-old boy with acute lymphoblastic leukemia (ALL) who developed NS during the tapering of immunosuppressants 5 months after an allogeneic HSCT (allo-HSCT). A renal biopsy was performed, and light and electron microscopy revealed minimal change disease (MCD). Although the response to treatment with steroids and tacrolimus was favorable, the child experienced two relapses of NS within the first 9 months after the initial response. A second allo-HSCT was performed to treat the relapse of ALL. After the second allo-HSCT, the remission of NS was maintained without recurrence for 5 years, even after the cessation of immunosuppressants.

CONCLUSIONS: Our patient who had ALL and developed NS after his first allo-HSCT, maintained remission from NS after a second allo-HSCT. This suggests that the immune cells from the first donor origin were associated with the pathogenesis of NS.