Minimal change disease onset after allogeneic stem cell transplant in donor and recipient siblings: A case report

Kidney disease is a frequent complication after haematopoietic stem cell transplant (SCT). Glomerulopathies are reported in up to 1%–6% of allogeneic SCT recipients. Commonest cause is membranous nephropathy, followed by minimal change disease (MCD). We describe a unique case report of a patient in receipt of a SCT whose sibling donor developed nephrotic syndrome secondary to MCD followed shortly thereafter by the same in the recipient. A female in her sixties received an HLA-matched sibling donor allogeneic SCT for haematological malignancy. Six months later, her donor developed nephrotic syndrome secondary to minimal change disease. A further 6 months thereafter, the recipient developed nephrotic syndrome, likely secondary to same. The disease in both patients was steroid-resistant and was successfully treated with cyclophosphamide and tacrolimus in the donor, and tacrolimus and rituximab in the recipient. This is an interesting hypothesis-generating case of MCD pathogenesis. The SCT donor kidney biopsy demonstrated weak linear IgG uptake of capillary loops and basement membrane on immunofluorescence, similar to that recently described in a biopsy-proven MCD patient cohort with nephrin autoantibodies co-localising with IgG in the basement membrane. SCT may have transmitted nephrin autoantibodies or other circulating factor, or donor-derived B-cells may have produced an autoantibody against a podocyte target antigen causing MCD in the donor transmitted by SCT and manifested in the recipient upon withdrawal of immunosuppressive GvHD treatment.