Two cases of ANCA-associated vasculitis in post-transplant kidney: relapse and de novo

Puzzling Interference in the Siemens Tacrolimus Assay in a Renal Transplant Patient: A Case Report

BACKGROUND

Therapeutic drug monitoring is a key tool for optimizing tacrolimus therapy in transplant recipients. The modified ACMIA assay from Siemens Healthcare Diagnostics is an immunoassay commonly used for tacrolimus monitoring, but it is not known whether this assay is resistant to interference from endogenous substances in real-world use.

OBJECTIVE

To describe a case of unexpected interference in tacrolimus monitoring using the modified ACMIA method in a kidney transplant recipient, and to highlight the importance of careful interpretation of laboratory results and effective communication with clinicians in optimizing patient care.

CASE DESCRIPTION

This case report describes a significant interference in the monitoring of tacrolimus in a kidney transplant recipient using the new ACMIA method. In this case, when aberrant results for tacrolimus were found using the new ACMIA method, they were re-analyzed using the CMIA method from Abbott. The presence of positive ANCA-MPO autoantibodies was found to be the most likely cause of the interference after an extensive workup.

CONCLUSIONS

This is the first report of major interference with the modified ACMIA tacrolimus method and emphasizes the importance of proper interpretation of laboratory results and effective communication with clinicians in optimizing patient care.

Anti-Neutrophil Cytoplasmic Antibody-Associated Vasculitis in Kidney Transplantation

Due to complex comorbidity, high infectious complication rates, an elevated risk of relapsing for primary renal disease, as well as inferior recipient and allograft survivals, individuals with anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAVs) are often considered as poor transplant candidates. Although several aspects of recurrent and de novo AAVs remain unclear, recent evidence suggests that kidney transplantation (KT) represents the best option, which is also the case for this particular subgroup of patients. Special counselling and individualized approaches are strongly recommended at the time of enlistment and during the entire post-transplant follow-up. Current strategies include avoiding transplantation within one year of complete clinical remission and thoroughly assessing the recipient for early signs of renal or systemic vasculitis. The main clinical manifestations of allograft AAV are impaired kidney function, proteinuria, and hematuria with ANCA positivity in most cases. Mixed results have been obtained using high-dose steroids, mycophenolate mofetil, or cyclophosphamide. The aim of the present review was to summarize the available literature on AAVs in KT, particularly focusing on de novo pauci-immune glomerulonephritis.

Rare Case Report of De-novo Pauci-immune Necrotizing Crescentic Glomerulonephritis in 1st-week Post-kidney Transplantation

Early post-transplant de-novo pauci-immune necrotizing crescentic glomerulonephritis occurring within the first week post transplantation has not been reported according to the literature search done by us. Here, we are reporting a 56 years male patient who underwent living spousal donor kidney transplantation for presumed diabetic nephropathy, and developed pauci-immune necrotizing crescentic glomerulonephritis (NCGN) on sixth day post-transplant. Post-renal transplant recurrence of disease in ANCA-associated vasculitis patients occurs within days to months. However, development of de-novo pauci-immune crescentic glomerulonephritis is a rare occurrence. We report this patient who developed probable pauci-immune de-novo NCGN which responded to treatment with plasmapheresis, steroids and cyclophosphamide.

Antibody-mediated rejection with the presence of glomerular crescents in a pediatric kidney transplant recipient: A case report

Glomerular crescents in kidney transplantation are indicative of severe glomerular injury and constitute a hallmark of RPGN. Their concurrence with ABMR has been rarely described only in adult patients. We report a case of 10-year-old boy with compound heterozygous Fin-major Finnish-type congenital nephrotic syndrome, who had received a deceased-donor kidney transplant 5 years before onset of acute kidney injury and nephrotic range proteinuria without hematuria. Kidney allograft biopsy illustrated 6 glomeruli with global sclerosis and 6 with remarkable circumferential or segmental cellular crescents. Negative glomerular immunofluorescence for immune-complex deposits and the absence of serum ANCA eliminated the presence of immune-mediated and ANCA-positive pauci-immune crescentic glomerulonephritis. Diagnosis of ABMR was based on the high levels of HLA class II DSA and the histological evidence of glomerulitis, peritubular capillaritis, and acute tubular injury with positive linear peritubular capillary C4d staining. The patient despite plasmapheresis and enhanced immunosuppressive treatment progressed to end-stage renal disease. We conclude that glomerular crescents may represent a finding of AMBR and possibly a marker of poor allograft prognosis in pediatric patients.

De novo pauci-immune glomerulonephritis in renal allografts

Pauci-immune glomerulonephritis in the native kidney presents with renal insufficiency, proteinuria, and hematuria, and is usually due to anti-neutrophil cytoplasmic antibodies. Rarely, kidney transplants can show this pattern as de novo disease. We performed a retrospective analysis in 10 cases of de novo pauci-immune glomerulonephritis. The mean time from transplant to diagnostic biopsy was 32 months (range, 4-96). All biopsies showed focal necrotizing or crescentic glomerulonephritis (mean 16% glomeruli, range 2-36%). Immunofluorescence and electron microscopy showed a pauci-immune pattern. No patients had evidence of systemic vasculitis. Anti-neutrophil cytoplasmic antibody results were available for 7 patients and were negative in all but one. Most patients had functioning grafts at one year after diagnosis. Two patients had repeat biopsies that showed continued active glomerulonephritis. We report the first clinicopathologic series of de novo pauci-immune glomerulonephritis which appears to be a unique pathologic entity that may occur early or late post-transplant and in our cohort is not associated with systemic vasculitis and usually not associated with anti-neutrophil cytoplasmic antibodies. The degree of crescent formation and renal impairment are milder than those of pauci-immune crescentic glomerulonephritis in the native kidney.

Recurrent and de novo Glomerulonephritis After Kidney Transplantation

The prevalence, pathogenesis, predictors, and natural course of patients with recurrent glomerulonephritis (GN) occurring after kidney transplantation remains incompletely understood, including whether there are differences in the outcomes and advances in the treatment options of specific GN subtypes, including those with de novo GN. Consequently, the treatment options and approaches to recurrent disease are largely extrapolated from the general population, with responses to these treatments in those with recurrent or de novo GN post-transplantation poorly described. Given a greater understanding of the pathogenesis of GN and the development of novel treatment options, it is conceivable that these advances will result in an improved structure in the future management of patients with recurrent or de novo GN. This review focuses on the incidence, genetics, characteristics, clinical course, and risk of allograft failure of patients with recurrent or de novo GN after kidney transplantation, ascertaining potential disparities between “high risk” disease subtypes of IgA nephropathy, idiopathic membranous glomerulonephritis, focal segmental glomerulosclerosis, and membranoproliferative glomerulonephritis. We will examine in detail the management of patients with high risk GN, including the pre-transplant assessment, post-transplant monitoring, and the available treatment options for disease recurrence. Given the relative paucity of data of patients with recurrent and de novo GN after kidney transplantation, a global effort in collecting comprehensive in-depth data of patients with recurrent and de novo GN as well as novel trial design to test the efficacy of specific treatment strategy in large scale multicenter randomized controlled trials are essential to address the knowledge deficiency in this disease.

Case report: de novo ANCA-associated vasculitis after kidney transplantation treated with rituximab and plasma exchange

Background

Anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis causes end-stage renal failure in up to a third of cases even with treatment. The disease recurs occasionally after kidney transplantation, but new onset of ANCA-associated vasculitis after transplantation is highly unusual. The use of rituximab or plasmapheresis for de novo disease after transplantation has not previously been reported.

Case presentation

Routine post-transplant follow-up for a 66-year old asymptomatic woman revealed a rise in creatinine from 1.8 to 2.6 mg/dl and increased proteinuria. She had received a cadaveric kidney transplant 20 months previously for end-stage autosomal dominant polycystic kidney disease. Renal allograft biopsy unexpectedly demonstrated pauci-immune glomerulonephritis with extracapillary proliferation and interstitial inflammation. Concurrent serum tested strongly positive for ANCA specific to proteinase 3 (PR3), but stored pre- and post-transplantation serum samples tested negative. These findings established a diagnosis of de novo ANCA-associated vasculitis in the renal allograft.

We started treatment with high-dose corticosteroid and rituximab. Despite this, serum creatinine continued to rise and glomerulonephritis remained active in a repeat biopsy. Escalation of the treatment with seven sessions of plasmapheresis led to a temporary improvement in creatinine. No further features of vasculitis emerged and PR3-ANCA titres declined. However, multiple infections complicated the recovery period and were associated with progressive loss of renal transplant function. Four months after the index presentation, transplant function became insufficient and dialysis was restarted.

Conclusions

De novo ANCA-associated vasculitis after renal transplantation is exceptionally rare. It poses a significant risk to graft survival even in the context of intensified immunosuppression. Management relies on clinical evidence from populations with native renal function, yet post-transplant patients may be at increased risk of treatment-related adverse events. Precautions against these risks are crucial in the delivery of care.

Recurrence of ANCA-associated vasculitis in a patient with kidney trasplant

Renal disease secondary to vasculitis associated with anti-neutrophil cytoplasmic antibodies (ANCA) can lead to chronic renal disease requiring renal replacement therapy. In these patients, kidney transplantation offers excellent long-term rates of allograft and patient survival; consequently, they can be trasplanted when the clinical disease activity has remitted. However, the risk of disease relapses in the renal allograft remains, although at lower rates due to modern immunosuppressive regimens. We describe the case of a male patient with extracapillary glomerulonephritis type III C-ANCA (+) who developed a recurrence in the renal allograft 8 years after transplantation. Intensive immunosupression with plasmapheresis controlled the disease.

De novo myeloperoxidase-antineutrophil cytoplasmic antibody (MPO-ANCA)-associated glomerulonephritis 31 years after living-donor kidney transplantation

A 61-year-old woman was admitted to our hospital because of an unexpected rise in serum creatinine (sCr) level with proteinuria and microhematuria. She had undergone living-donor kidney transplantation 31 years before for end-stage renal disease caused by chronic glomerulonephritis (GN). On admission, her sCr was 1.27 mg/dL which was increased from 0.6 mg/dL, urinary protein/creatinine ratio was 1.39 g/gCr, and urinary red blood cell count was more than 100 per high power field. The allograft biopsy revealed crescentic glomerulonephritis with moderate to severe tubulointerstitial inflammation. Immunofluorescence staining yielded only a minimal staining for immunoglobulin A, and negative C4d in peritubular capillary. Since increased myeloperoxidase-antineutrophil cytoplasmic antibody (MPO-ANCA) titer of 45.5 U/mL was detected, we made the diagnosis of post-transplant MPO-ANCA-associated GN. She was treated with three doses of bolus methylprednisolone (500 mg) followed by oral prednisolone therapy. Her sCr was stable at 1.20 mg/dL thereafter. ANCA-associated GN should be considered in older kidney transplant patients with new-onset urinary abnormalities because typical systemic symptoms and vasculitis in other organs might be masked by maintenance immunosuppression.

De novo glomerular diseases after renal transplantation

Glomerular diseases developing in the kidney allograft are more often recurrences of the original disease affecting the native kidneys. However, in an undefined number of cases de novo, glomerular diseases unrelated to the original disease in the native kidneys can develop in the transplanted kidney. The clinical presentation and histologic features of de novo diseases are often similar to those features observed in patients with primary or secondary GN in the native kidneys. However, in transplanted kidneys, the glomerular, vascular, and tubulointerstitial changes are often intertwined with structural abnormalities already present at the time of transplant or caused by antibody- or cell-mediated allograft rejection, immunosuppressive drugs, or superimposed infection (most often of a viral nature). The pathophysiology of de novo glomerular diseases is quite variable. In rare cases of de novo minimal change disease, circulating factors increasing the glomerular permeability likely participate. Maladaptive hemodynamic changes and tissue fibrosis caused by calcineurin inhibitors or other factors may be involved in the pathogenesis of de novo FSGS. The exposure of cryptic podocyte antigens may favor the development of de novo membranous nephropathy. Many cases of de novo membranoproliferative GN are related to hepatitis C virus infection. Patients with Alport syndrome lacking antigenic epitopes in their glomerular basement membrane may develop antibodies against these glomerular basement membrane antigens expressed in the transplanted kidney. Infection may cause acute GN to have a heterogeneous clinical presentation and outcome. De novo pauci-immune GN in renal transplant is rare. Preexisting or acquired intolerance to glucose may, in the long term, cause diabetic nephropathy. The prognosis of de novo diseases depends on the type of GN, the severity of lesions caused by the alloimmune response, or the efficacy of immunosuppressive therapy. In most cases, the management of de novo glomerular diseases is empirical or elusive.

Recurrence of anti-neutrophil cytoplasmic antibody vasculitis in the kidney allograft

We report a case of recurrent anti-cytoplasmic neutrophil antibody (ANCA)-associated vasculitis post kidney transplantation. A 60-year-old woman underwent uncomplicated deceased-donor kidney transplantation for end-stage renal disease (ESRD) secondary to myeloperoxidase-specific ANCA-associated vasculitis, after six years of haemodialysis, and clinical remission. Immunosuppression was with tacrolimus/mycophenolate and prednisolone after basiliximab induction therapy. Five weeks post-transplantation, an allograft biopsy, done for a rising creatinine and glomerular haematuria, revealed pauci-immune crescentic glomerulonephritis. This was treated with pulse methylprednisolone, increase in maintenance prednisolone, 7 sessions of plasma exchange, and replacement of mycophenolate with cyclophosphamide. Tacrolimus was continued throughout. After 3 months of therapy a repeat allograft biopsy showed quiescent vasculitis. The cyclophosphamide was then ceased, and mycophenolate reinstituted. The patient has maintained clinical and histological stability. Reported rates of ANCA-associated vasculitis recurrence post-kidney transplantation have varied but are low compared with other types of glomerulonephritis and seemed to have further declined in the era of modern immunosuppression. Given the low recurrence rate and excellent outcomes in suitable patients, kidney transplantation remains the optimal form of renal replacement therapy for ESRD due to ANCA-associated vasculitis. Whilst re-introduction of cyclophosphamide has been the mainstay of therapy, additional reported successful therapeutic strategies have included pulse methylprednisolone, plasma exchange and rituximab. Further study on the most effective and safest treatment options would be of use given the current paucity of data in this area.