Nephrotic syndrome as a complication of chronic graft-versus-host disease after allogeneic haemopoietic stem cell transplantation.

Nephrotic syndrome (NS) is a rare complication following allogeneic haemopoietic stem cell transplantation (allo-HSCT), with limited current understanding of its pathogenesis. Here, we describe four cases of NS following allo-HSCT diagnosed at our institutions to identify key clinical and pathological features. In addition, a PubMed search was performed to identify existing reports that were pooled together with our cases for analysis. NS occurred as a late complication following allo-HSCT, with median onset 19.5 months after transplant (range: 3.9-84 months). The most common histopathology observed was membranous nephropathy; however, cases of minimal change disease have also been reported. There is a high incidence of prior extra-renal graft-versus-host disease (GvHD), with all four of our cases and 82% of published cases having prior GvHD. Glucocorticosteroids are the most common treatment, with variable degrees of response. Responses to immunosuppression with calcineurin inhibitors and rituximab have been described in steroid-refractory cases.