Concurrent treatment with rituximab and plasma exchange for severe refractory granulomatosis with polyangiitis: A case report

RATIONALE

Rituximab is recommended to induce remission of severe granulomatosis with polyangiitis (GPA). Plasma exchange (PE) may be considered in the setting of rapidly progressive glomerulonephritis (RPGN) with a serum creatinine increase of more than 5.6 mg/dl or diffuse alveolar hemorrhage (DAH). However, there are no sufficient studies on combination therapy with rituximab and PE in GPA.

PATIENT CONCERNS

A 23-year-old woman was admitted with fever, abdominal pain, and diarrhea on suspicion of infectious colitis. Colonoscopy showed hemorrhagic colitis and antibiotic treatment was ineffective. Physical examination revealed episcleritis and skin lesions similar to Janeway lesions or Osler nodes on her palms and soles. Transesophageal echocardiogram (TEE) revealed mitral valve vegetation mimicking infective endocarditis. However, no pathogen was grown in the blood culture. Ten days after admission, blood-tinged sputum and respiratory distress developed. Imaging studies of lung, bronchoscopy, and bronchoalveolar lavage indicated DAH. Moreover, serum creatinine levels rapidly increased from 0.8 mg/dl to 6.1 mg/dl with proteinuria.

DIAGNOSIS

The patient was diagnosed with GPA and non-infectious endocarditis, DAH, and RPGN, based on a biopsy which revealed pauci-immune crescentic glomerulonephritis with granuloma and leukocytoclastic vasculitis and antineutrophil cytoplasmic antibodies against proteinase 3- positivity.

INTERVENTIONS

Initial methylprednisolone pulse therapy (1 g daily for 3 days) proved unsuccessful. After initiating PE, creatinine levels began to slowly decline, but DAH continued to deteriorate. Rituximab combined with PE therapy was considered. We performed PE every 2 to 3 days for 5 total treatments combined with rituximab (375 mg/m, once weekly for 4 weeks).

OUTCOMES

After the combination treatment of rituximab and PE, alveolar hemorrhage stopped. Chest X-ray and laboratory data, including serum creatinine and hemoglobin, notably improved. Mitral valve vegetation was no longer observed in follow-up TEE. GPA remained stable with low dose prednisolone and immunosuppressants over a follow-up period of 5 years.

LESSONS

This case suggests that the use of rituximab and concurrent PE may represent a promising combination for severe and refractory GPA.

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.

The effect of histopathologic and clinical features on allograft survival in renal transplant patients with antibody-mediated rejection

Background: Antibody-mediated rejection is a frequent cause of graft failure; however, prognostic indications of this complication have not been well defined. The aim of this study was to evaluate the association of histopathological and clinical features and to determine the effect of these findings on allograft survival in patients with AMR.

Methods: Fifty-two patients suffered from AMR (30 male; mean age 39 ± 11 years) were included in the study. Data were investigated retrospectively and graft survival was analyzed. All transplant biopsies were evaluated according to Banff 2009 classification.

Results: Of the 52 cases, 45 were transplanted from living-donors. Twenty-one patients were diagnosed in the first 3-months after transplantation. Graft survival was 65% at 12 months and 54% at 36 months. Mean serum creatinine at time of biopsy was 3.8 ± 3.6 mg/dL. Thirty-five of the 52 cases showed diffuse C4d positivity, 12 cases showed focal and 5 remained C4d negative. One of the patients died, 13 experienced graft loss and 38 survived with functioning grafts. Serum creatinine levels at time of biopsy were correlated with graft survival (p = .021: OR = 1.10: 95 % CI = 1.015–1.199). In terms of the impact of pathological findings; tubulitis (p=.007: OR = 2.62: 95 % CI = 1.301–5.276), intimal arteritis (p=.017: OR = 2.85: 95% CI = 1.205–6.744) and interstitial infiltration (p=.004: OR = 3.37: 95% CI = 1.465–7.752) were associated with graft survival.

Conclusions: Serum creatinine at time of biopsy, tubulitis, intimal arteritis and interstitial infiltration were significantly associated with graft survival. Antibody-mediated rejection is associated with reduced long-term graft survival.

An Anti-C1s Monoclonal, TNT003, Inhibits Complement Activation Induced by Antibodies Against HLA

Antibody-mediated rejection (AMR) of solid organ transplants (SOT) is characterized by damage triggered by donor-specific antibodies (DSA) binding donor Class I and II HLA (HLA-I and HLA-II) expressed on endothelial cells. While F(ab')2 portions of DSA cause cellular activation and proliferation, Fc regions activate the classical complement cascade, resulting in complement deposition and leukocyte recruitment, both hallmark features of AMR. We characterized the ability of an anti-C1s monoclonal antibody, TNT003, to inhibit HLA antibody (HLA-Ab)-induced complement activation. Complement deposition induced by HLA-Ab was evaluated using novel cell- and bead-based assays. Human aortic endothelial cells (HAEC) were cultured with HLA-Ab and human complement; production of activated complement proteins was measured by flow cytometry. Additionally, C3d deposition was measured on single antigen beads (SAB) mixed with HLA-Ab and human complement. TNT003 inhibited HLA-Ab mediated complement deposition on HAEC in a concentration-dependent manner; C3a, C4a and C5a anaphylatoxin production was also diminished by TNT003. Finally, TNT003 blocked C3d deposition induced by Class I (HLAI-Ab)- and Class II (HLAII-Ab)-specific antibodies on SAB. These data suggest TNT003 may be useful for modulating the effects of DSA, as TNT003 inhibits complement deposition and split product formation generated by HLA-I/II-Ab in vitro.

Review of bortezomib treatment of antibody-mediated rejection in renal transplantation

SIGNIFICANCE

Development of donor-specific antibodies (DSA) after kidney transplantation is associated with reduced allograft survival. A few strategies have been tested in controlled clinical trials for the treatment of antibody-mediated rejection (AMR), and no therapies are approved by regulatory authorities. Thus development of antihumoral therapies that provide prompt elimination of DSA and improve allograft survival is an important goal.

RECENT ADVANCES

Proteasome inhibitor (PI)-based regimens provide a promising new approach for treating AMR. To date, experiences have been limited to off-label bortezomib use in AMR. Key findings with PI-based therapy are that they provide effective primary and rescue therapy for AMR by prompt reduction in immunodominant DSA and improvements in histologic and renal function. Early and late AMR differ immunologically and in response to PI therapy. Bortezomib-related toxicities in renal transplant recipients are similar to those observed in the multiple myeloma population.

CRITICAL ISSUES

Although preliminary evidence with PI therapy for AMR is encouraging, the evidence is limited. Larger, prospective, randomized controlled trials with long-term follow up are needed. Advancement in endpoints of clinical trial designs and rigorous clinical trials with more standardized adjunct therapies are also required to explore the risks and benefits of AMR treatment modalities.

FUTURE DIRECTIONS

In the next few years, new PIs are likely to be introduced and new approaches would be developed for achieving synergy with PIs. The ultimate goal will be to develop a regimen that delivers reliable, rapid, complete, and durable elimination of DSA with an acceptable safety profile.

Better understanding of transplant glomerulopathy secondary to chronic antibody-mediated rejection

Transplant glomerulopathy (TG) is generally accepted to result from repeated episodes of endothelial activation, injury and repair, leading to pathological abnormalities of double contouring or multi-layering of the glomerular basement membrane. TG is a major sequel of chronic active antibody-mediated rejection (cABMR), from pre-existing or de novo anti-HLA antibodies. Hepatitis C infection, thrombotic microangiopathy or other factors may also contribute to TG development. TG prevalence is 5-20% in most series, reaching 55%, in some high-risk cohorts, and is associated with worse allograft outcomes. Despite its prevalence and clinical significance, few well-studied treatment options have been proposed. Similar to desensitization protocols, plasmapheresis with or without immunoabsorption, high-dose intravenous immunoglobulin, rituximab, bortezomib and eculizumab have been proposed in the treatment of TG due to cABMR individually or in various combinations. Robust clinical trials are urgently needed to address this major cause of allograft loss. This review summarizes the current knowledge of the epidemiology, etiology, pathology, and the preventive and treatment options for TG secondary to cABMR.

Mannose-binding lectin-2 and ficolin-2 gene polymorphisms and clinical risk factors for acute rejection in kidney transplantation

INTRODUCTION

There is growing evidence that the lectin pathway is significantly associated with acute rejection. Rare studies associated both gene polymorphisms of MBL2 and FCN2 with acute rejection after kidney transplantation. The aim of the present study was to investigate the role of the lectin gene profile and clinical risk factors such as PRA level on acute rejection in kidney transplant recipients.

METHODS

We prospectively analyzed 157 kidney transplant recipients with and without acute rejection. A total of 6 well-known functional single-nucleotide polymorphisms in the MBL2 gene and 5 in the FCN2 gene of the recipients were determined by gene sequencing. MBL2 and FCN2 genotypic variants were analyzed for association with the incidence of acute rejection within the first year after kidney transplantation.

RESULTS

After adjusting for variables of P<0.2, we found the differences in the incidence of acute rejection were only according to panel-reactive antibodies (odds ratios (OR) = 6.468, 95% confidence intervals (CI)= 2.017-20.740, P = 0.002) and the HH genotypes of MBL2 promoter -550 (OR = 2.448, 95%CI = 1.026-5.839, P = 0.044).

CONCLUSION

Panel-reactive antibodies and the HH genotypes of MBL2 promoter -550 have significant impacts on the risk of developing acute rejection after kidney transplantation.

Therapeutic plasma exchange for the treatment of pediatric renal diseases in 2013

Therapeutic plasma exchange is an extracorporeal treatment modality that removes systemic circulating pathologic factors or replaces absent plasma components and plays a role in many nephrologic conditions. It presents a number of technical challenges in the pediatric population but has become an increasingly common practice in pediatric nephrology over the past several decades. While prospective evidence is often lacking, our increased understanding of the molecular pathogenesis underlying many pediatric renal diseases provides sound reasoning for the use of plasma exchange in treating these conditions. This review will present the currently accepted indications for plasma exchange in children, the technical aspects of the procedure and its potential complications.

Management of antibody-mediated rejection in transplantation

Despite intensive traditional immunosuppressive therapy, rates of graft loss have approximated 15% to 20% at 1 year following antibody-mediated rejection (AMR) in solid organ transplant recipients. Therefore, the development of antihumoral therapies that provide prompt elimination of donor-specific anti-HLA antibodies and improve allograft survival is an important goal. Traditional treatment modalities for AMR deplete B-cell populations but not the cell at the source of antibody production, the mature plasma cell. Plasma cell-targeted therapies using proteasome inhibition is a novel approach to treating AMR. This review discusses current and emerging treatment modalities used for AMR.

Use of apheresis in solid organ transplantation

Apheresis is an effective desensitization modality for removing antibodies against donor-specific human leukocyte antigens or ABO blood type antigens to facilitate transplantation. Apheresis is also used to treat acute antibody-mediated rejection, in conjunction with immunosuppressive medications, in recurrent focal and segmental glomerulosclerosis and other glomerular diseases, in correction of coagulopathy, in supportive therapy in acute liver failure patients awaiting liver transplant, and in the treatment of drug-induced thrombotic microangiopathy. Transplant recipients who receive apheresis need close monitoring for infections and for potential bleeding complications associated with surgery or biopsy.