[Current insights about recurrence of glomerular diseases after renal transplantation]

[Recurrence of post-kidney transplant glomerulonephritis: clinicopathological characteristics]

INTRODUCTION

Glomerulonephritis (GN) is one of the main causes of end-stage renal disease worldwide and therefore a frequent cause of kidney transplantation, with the possibility of recurrence of GN (Recurrent Glomerulonephritis [GNR]) in the transplanted kidney. The purpose of this study was to identify the clinic and pathological characteristics of GNR in a population of transplant patients.

MATERIALS AND METHODS

A descriptive, retrospective study was carried out in 109 patients in whom GNR was documented in the transplanted kidney demonstrated by biopsy during the period between 1998-2021.

RESULTS

Of 109 patients, the most frequent GNR was GNIgA, in 38.5% (42), followed by FSGS with 31.2% (34); These same entities were the ones that presented the greatest graft dysfunction, with 50% (21) and 26.2% (11) respectively. The ranges of proteinuria indicated by the biopsy were 31.2% (34) with a range of 500 to 3500mg/24h and 34.9% (38) with proteinuria >3500mg/24h. In relation to the time elapsed between the transplant and the diagnosis of GNR, 33% (36) of the cases were >5 years, followed by 1 to 5 years in 26.6% (29). Recurrence in patients with GNIgA occurred mostly after 5 years post-transplant with 45.2% (19) and for FSGS it was between 1 and 6 months.

CONCLUSION

We found a general frequency of GNR presentation similar to those reported by other centers where biopsies are performed for clinical indication, finding that the GN that recurred most frequently are GNIgA and FSGS.

Kidney Transplantation for Focal Segmental Glomerulosclerosis: Can We Prevent Its Recurrence? Personal Experience and Literature Review

Background: Primary focal segmental glomerulosclerosis (FSGS) is associated with a high risk of recurrence after kidney transplantation with a major risk of graft loss despite preventive or curative treatments. Aim: to assess graft survival in FSGS kidney-transplant recipients and to compare those that had a relapse with those that had no relapse. Patients/Methods: we included 17 FSGS kidney-transplant recipients between January 2000 and January 2020, separated retrospectively into two groups (recurrences: n = 8 patients; no recurrences: n = 9 patients). FSGS recurrence was defined as having proteinuria of ≥3 g/g or urinary creatinine of ≥3 g/day. All patients received an induction therapy; maintenance immunosuppressive therapy at post-transplantation relied on tacrolimus/mycophenolate mofetil/steroids. In order to prevent or treat FSGS recurrence, patients received apheresis sessions plus rituximab. Results: FSGS recurrence rate was 47%. All patients that relapsed with a first graft also relapsed with subsequent grafts. Median time to recurrence was 3 (min: 1; max: 4745) days, despite rituximab/apheresis prophylaxis. Mean age was significantly lower in the relapsers (group 1) than in the non-relapsers (group 2); i.e., 47 ± 11 vs. 58 ± 9 years (p = 0.04). Time to progression to stage 5 chronic kidney disease (CKD) and young age at FSGS diagnosis were lower in group 1 compared to group 2; i.e., 5 (min: 1; max: 26) vs. 2 (min: 1; max: 26) years, and 16 (min: 4; max: 55) vs. 34 (min: 6; max 48) years, respectively. There was no difference between the two groups in terms of progression to CKD stage 5 on the native kidneys, averaging 7 years in both groups (p = 0.99). In group 1, seven patients received rituximab/apheresis prophylaxis, although this did not prevent the recurrence of FSGS. Conclusion: pretransplant prophylaxis with plasmapheresis/rituximab did not appear to reduce the risk of recurrence of primary FSGS on the graft, but could allow remission in the event of recurrence.