Clinico-pathological correlations and outcomes of de novo glomerular diseases in patients after haematopoietic stem cell transplantation

Background Various glomerular pathologies have been reported in patients who have undergone haematopoietic stem cell transplantation (HSCT), but the data on clinico-pathological correlations and clinical outcome remain limited. Methods We analysed the clinical and histopathological data of patients who had biopsy-proven de novo glomerular diseases after HSCT since 1999. Results A total of 2204 patients underwent HSCT during the period 1999-2021, and 31 patients (1.4%) developed de novo glomerular diseases after a mean duration of 2.8 +/- 2.7 years after HSCT. Fifteen of these patients (48.4%) had graft-versus-host-disease prior to or concomitant with renal abnormalities. Proteinuria and eGFR at the time of kidney biopsy were 4.1 +/- 5.3 g/day and 50.8 +/- 25.4 mL/min/1.73 m(2), respectively. Kidney histopathologic diagnoses included thrombotic microangiopathy (TMA) (38.7%), membranous nephropathy (MN) (25.8%), mesangial proliferative glomerulonephritis (12.9%), minimal change disease (9.7%), focal segmental glomerulosclerosis (9.7%) and membranoproliferative glomerulonephritis (3.2%). Immunosuppressive treatment was given to patients who presented with nephrotic-range proteinuria and/or acute kidney injury, while renin-angiotensin-aldosterone blockade was given to all patients with proteinuria >= 1 g/day, with complete and partial response rates of 54.8% and 19.4%, respectively. One patient with TMA progressed to end-stage kidney disease after 24 weeks, and two patients, one with TMA and one with MN, (6.4%) progressed to chronic kidney disease (CKD) Stage >= 3. Kidney and patient survival rates were 96.6% and 83.5%, respectively, at 5 years. Conclusion De novo glomerular diseases with diverse histopathologic manifestations affect 1.4% of patients after HSCT, and approximately 10% develop progressive CKD.