Effect of Post-transplant Double Filtration Plasmapheresis on Recurrent Focal and Segmental Glomerulosclerosis in Renal Transplant Recipients

Rituximab Use in the Management of Childhood Nephrotic Syndrome

Childhood nephrotic syndrome is a challenging and often persistent renal disorder, and its incidence varies between different ethnicities and regions. Corticosteroids have been the main treatment for decades and are effective in most children with idiopathic NS, although 10-15% of these children become steroid resistant. Furthermore, some initially steroid sensitive children follow a steroid dependent or frequently relapsing course and are therefore at increased risk for developing steroid toxicity. In such children, alternative immunosuppressive medications are used to induce and/or maintain remission of NS. One such drug, rituximab, is a monoclonal antibody directed against the B lymphocyte CD20 marker which induces depletion of B cells, and has shown promising results in the management of NS in children. In this review, we summarize recent studies on the efficacy and safety of rituximab in the different types of childhood nephrotic syndrome, the known and potential mechanisms of action of rituximab, its possible complications and side effects, and the available and potential biomarkers of rituximab activity.

Effects of different lipoprotein apheresis methods on serum protein levels

BACKGROUND

A total plasma exchange was the first extracorporeal method to treat patients with severe hypercholesterolemia. But in the long run it has several disadvantages. The newer lipoprotein apheresis (LA) methods claim to be more selective with respect to the removal of atherogenic lipoproteins and thus are supposed to avoid an additional protein loss.

METHODS

We wanted to compare the effect of these methods on serum protein concentrations (total serum protein, albumin, proteins measured with electrophoresis, immunoglobulins, fibrinogen, transferrin, and ferritin) which were checked before and after a single LA session in 75 patients. All patients underwent active LA treatment using 6 different LA methods (HELP, TheraSorb(®) LDL, DALI, Lipidfiltration, Liposorber D, MONET). Post-apheresis concentrations were corrected for changes in hematocrit.

RESULTS

The slightest impact on total serum protein was observed with the whole-blood methods. Liposorber D showed the least reduction of albumin levels. All LA methods had a small effect on alpha1-globulins and beta-globulins, but alpha2-and gamma-globulins were reduced to a different extent. A major effect was seen on the immunoglobulins when filtration methods were applied. In the patients treated with MONET, both pre- and post-apheresis Immunoglobulin M concentrations were below the normal range. HELP and the filtration methods significantly reduced the fibrinogen concentrations. The filtration methods also decreased ferritin levels but the post-apheresis ferritin levels were still in the normal range.

CONCLUSION

All LA methods had an influence on protein concentrations. At present, these findings will not yield an individualized treatment approach for any selective LA method due to the lack of prospective comparative studies. At minimum, special attention should be paid to protein concentrations in patients suffering from protein deficit.

Plasma Exchange for the Recurrence of Primary Focal Segmental Glomerulosclerosis in Adult Renal Transplant Recipients: A Meta-Analysis

Background. Posttransplant recurrence of primary focal segmental glomerulosclerosis (rFSGS) in the form of massive proteinuria is not uncommon and has detrimental consequences on renal allograft survival. A putative circulating permeability factor has been implicated in the pathogenesis leading to widespread use of plasma exchange (PLEX). We reviewed published studies to assess the role of PLEX on treatment of rFSGS in adults. Methods. Eligible manuscripts compared PLEX or variants with conventional care for inducing proteinuria remission (PR) in rFSGS and were identified through MEDLINE and reference lists. Data were abstracted in parallel by two reviewers. Results. We detected 6 nonrandomized studies with 117 cases enrolled. In a random effects model, the pooled risk ratio for the composite endpoint of partial or complete PR was 0,38 in favour of PLEX (95% CI: 0,23–0,61). No statistical heterogeneity was observed among included studies (I² = 0%, p = 0,42). On average, 9–26 PLEX sessions were performed to achieve PR. Renal allograft loss due to recurrence was lower (range: 0%–67%) in patients treated with PLEX. Conclusion. Notwithstanding the inherent limitations of small, observational trials, PLEX appears to be effective for PR in rFSGS. Additional research is needed to further elucidate its optimal use and impact on long-term allograft survival.

Recurrent focal segmental glomerulosclerosis after kidney transplantation

Focal segmental glomerulosclerosis (FSGS) is an important cause of glomerular disease in children and adolescents and nearly 50 % of affected patients will progress to end-stage kidney disease over a 5 to 10-year period. Unfortunately, there is no established treatment for disease in the native kidney. Moreover, up to 55 % of patients develop recurrent disease after receiving a kidney transplant, with a substantially higher risk in patients who have already experienced recurrent disease in a prior transplant. A number of clinical and laboratory factors have been identified as risk factors for this complication. In addition, new investigations into podocyte biology and circulating permeability factors have shed light on the cause of recurrent the disease. While a number of novel therapeutic agents have been applied in the management of this problem, there still is no proven treatment. In this review, we summarize recent advances in the epidemiology, pathophysiology, and treatment of recurrent FSGS in pediatric patients who have received a kidney transplant.

Recent progress in the pathophysiology and treatment of FSGS recurrence

Focal segmental glomerulosclerosis (FSGS) is a glomerular disease characterized by proteinuria, frequent progression to end-stage renal disease, and recurrence after kidney transplantation in ∼25% of patients, which negatively impacts long-term allograft survival. Experimental studies suggest that abnormalities in T and, possibly, B cells may represent one initial pathogenic trigger, leading to podocyte injury and progressive loss. New data also support the existence of circulating permeability factors able to damage the podocytes, but no single molecule has been consistently identified as the causal pathogenic element in FSGS recurrence. Unfortunately, major progress from mechanistic studies has not translated into substantial advancements in patient treatment, with plasmapheresis (PP) and high doses of cyclosporine (CsA) remaining the mainstays of therapy. Despite consistent experimental and clinical evidence that treatment of proteinuria slows renal function decline in proteinuric nephropathies, maximal use of antiproteinuric agents such as renin angiotensin system antagonists is not routine in the management of FSGS recurrence. More recently, encouraging results have been reported with anti-CD20 depleting antibody rituximab, but further studies are needed to establish its safety/efficacy profile.

Therapeutic apheresis rescue mission: recurrent focal segmental glomerulosclerosis in renal allografts

Recurrent idiopathic focal segmental glomerulosclerosis (FSGS) after renal transplantation can lead to a rapid failure of the allograft. A circulating, nonimmunoglobulin factor appears to be important in the pathogenesis of this complication in many cases. Between 30% and 50% of transplant recipients with FSGS develop recurrent disease. Three major risk factors for recurrence have been identified: short duration of native kidney disease, history of recurrence with previous kidney transplant, and pediatric aged recipients. Although no properly controlled trials have been conducted, plasmapheresis has emerged as one of the important treatment modalities for this entity. Retrospective studies prior to the routine use of plasmapheresis showed graft loss rates as high as 80%, a rate much higher than that seen in more recent series managed with plasmapheresis. Duration and intensity of treatment of plasmaphersis have not been studied rigorously, but in most case series, plasmapheresis was continued until a clear diminution of proteinuria was seen. The benefit of other adjuvant therapies for this condition remains unclear, but also may play a role in the treatment of this entity.

Double filtration plasmapheresis in antibody-incompatible kidney transplantation

Double filtration plasmapheresis (DFPP) was used in preference to plasma exchange in our program of antibody-incompatible transplantation, to treat higher volumes of plasma. Forty-two patients had 259 sessions of DFPP, 201 pre-transplant and 58 post-transplant. At the first treatment session, the mean plasma volume treated was 3.81 L (range 3-6 L), 55.5 mL/kg (range 36.2-83.6 mL/kg). Serum IgG fell by mean 59.4% (SD 10.2%), and IgM by 69.3% (SD 16.1%). Nine patients did not require increases in plasma volumes treated, and six did not tolerate higher plasma volumes. In the remaining patients, the mean maximum plasma volume treated pre-transplant was 6.67 L (range 4-15 L), 96.1 mL/kg (range 60.2-208.9 mL/kg). The complement dependent cytotoxic crossmatch was positive in 14 cases pre-treatment, and remained positive in six (42.8%) cases. The flow cytometric crossmatch was positive in 29 cases pre-treatment, and in 21 (72.4%) after DFPP. Post-transplant, DFPP was ineffective at reducing donor specific antibody levels during periods of rapid donor specific antibody synthesis. Post-transplant, the one year graft survival rate was 94%, although there was a high rate of early rejection. In summary, DFPP enabled the treatment of plasma volumes that were almost double those that would have been feasible with plasma exchange. Despite this, most patients were transplanted with a positive crossmatch, and DFPP post-transplant was unable to control rising antibody levels.

Recurrence of focal segmental glomerulosclerosis in renal allograft: an in-depth review

Focal segmental glomerulosclerosis is a major cause of chronic kidney disease requiring transplantation in children. Recurrence rate in the renal allograft transplantation is as high as 50%. Recurrence of FSGS is associated with renal dysfunction and early graft loss. To date, there is no established therapy for recurrent FSGS after renal transplant. We have reviewed the current English literature in order to summarize current practices with emphasis on graft outcome. We conclude that despite multiple approaches to the post transplant management of recurrent FSGS, none have been shown to be consistently beneficial. Currently, pheresis combined with high dose anti-calcineurin with or without rituximab seems to be the most promising. Further controlled studies are needed to define the optimal therapeutic regimens to treat recurrent of FSGS.

Kidney transplantation for primary focal segmental glomerulosclerosis: outcomes and response to therapy for recurrence

BACKGROUND

For a subset of adults and children with primary focal segmental glomerulosclerosis (FSGS), proteinuria and renal dysfunction recur after kidney transplantation (KTx). Predicting recurrence and response to plasmapheresis (PP) or other interventions remains problematic.

METHODS

The prevalence, recurrence rate, outcomes, and treatment responses of patients with FSGS were determined among 1573 KTx recipients. Although 5.0% carried some diagnosis of FSGS, only 1.9% (n=30) met strict diagnostic criteria for primary FSGS including biopsy-proven FSGS, lack of secondary factors, negative family history, and progression to end-stage renal disease within 10 years.

RESULTS

Of these, 47% had recurrent FSGS compared with 8% of those not meeting strict criteria (P<0.001). Recurrence was more common in children compared with adults (86% vs. 35%, P=0.01). Graft survival was lower for recipients with primary FSGS compared with all others and inferior graft survival was attributable to recurrent FSGS. Fourteen patients received PP preemptively (pre-KTx) or therapeutically (post-KTx) for recurrent disease. Four pediatric patients additionally received anti-CD20 (rituximab) therapy. Of the different treatment approaches, only PP combined with rituximab was associated with prolonged remission of proteinuria.

CONCLUSIONS

The results indicate that patients at high risk for FSGS recurrence can be identified and may benefit from carefully planned peritransplant interventions.

Focal segmental glomerular sclerosis in renal transplant recipients: predicting early disease recurrence may prolong allograft function

Recurrence of focal segmental glomerular sclerosis (FSGS) in the allograft following renal transplantation can be graft threatening. To assess risk factors associated with FSGS recurrence, we analyzed 22 patients with FSGS who underwent transplantation between 1996 and 2004. Five patients (Group I, 23%) developed FSGS post-transplantation. Of these patients, 60% had undergone bilateral nephrectomy (BN) for progressive disease compared with none of the patients that were free of recurrence (Group II) (p = 0.0006). Other factors linked with recurrent FSGS were time to first dialysis (Group I: 3.1 +/- 1.1 yr vs. Group II: 11.9 +/- 1.9 yr; p = 0.03), pre-transplant proteinuria (Group I: 7.0 +/- 1.8 g/d vs. Group II: 2.5 +/- 0.7 g/d; p = 0.02), young age at transplantation (p = 0.09) and female sex (Group I: 80% vs. Group II: 24%; p = 0.021). Eighty percent of Group I patients received a living related transplant vs. 24% in Group II (p = 0.021). All grafts continue to function at last follow-up with comparable serum creatinines. Overall, post-transplant FSGS recurrence may be associated with BN, severity of pre-transplant FSGS, female gender, and living donation. These patients should be monitored closely for early recurrence and may benefit from early plasmapheresis to restore and facilitate long-term graft function.

A Controlled Study of Double Filtration Plasmapheresis in the Treatment of Active Rheumatoid Arthritis

BACKGROUND

Double-filtration plasmapheresis with a plasma fractionator pore size of 20 nm should selectively remove large molecular weight substances like rheumatoid factor and IgM. This was proposed to be more likely to be helpful for rheumatoid arthritis than standard plasma exchange.

OBJECTIVE

To evaluate the efficacy of double-filtration plasmapheresis (DFPP) in the treatment of patients with active rheumatoid arthritis.

METHODS

Eighty-two patients were randomly assigned, 42 to the DFPP group and 40 to the no-DFPP group. All patients received sulfasalazine (0.75 g 3 times daily) plus methotrexate (10 mg orally once weekly). All patients had been on stable doses for more than 3 months. DFPP was performed once a week for 2 to 3 sessions. A total of 121 plasmapheresis procedures were performed in 42 patients. Control patients did not receive sham DFPP. The efficacy measures recorded 1 day after the final treatment and every month in follow-up for 4 to 22 months included the American College of Rheumatology (ACR) 20%, 50%, and 70% improvement criteria (ACR20, ACR50, and ACR70), the Health Assessment Questionnaire estimate of disability and the disease activity index.

RESULTS

Patients in the DFPP group had ACR20, ACR 50, and ACR70 improvements immediately after the last treatment of 100%, 92.9%, and 81.0%, when compared with the patients in no-DFPP group 17.5%, 0%, and 0% (P < 0.001). Significant change from baseline was observed in Health Assessment Questionnaire scores in the DFPP group, but not in the no-DFPP group (P < 0.001). The changes from baseline in the disease activity scores were significantly greater than in the no-DFPP group (P < 0.001). Improvements were maintained during follow-up of 7 to 22 months.

CONCLUSION

This open trial showed that DFPP therapy significantly altered the signs and symptoms of active rheumatoid arthritis. There were increases in physical function and improvement in quality of life. This is proposed as an approach that merits further investigation.

What are the indications for plasma exchanges in autoimmune diseases?: The registry of the Société Française d’Hémaphérèse

The use of plasma exchange (PE) in the autoimmune diseases is encouraged in France. Since 1990, the national registry of PE allows an analysis of the evolution of the coverage of these pathologies. The variation of the number of patients treated by PE is correlated in respect to the results of the therapeutic studies. After a decrease of PE activity in these indications during the 90s, one observes a new increase of the patients treated because of the validation of new indications. Autoimmune diseases represent the third cause of morbidity in developed countries, with a global prevalence of 5%, and concerns four groups of pathologies of organs or systems (neurology, haematology, nephrology and vasculitis). In 1976, Lockwood demonstrated the place of plasma exchanges (PE) in Goodpasture's syndrome [Lockwood CM, Rees AJ, Pearson TA, Evans DJ, Peters DK, Wilson CB. Immunosuppression and plasma exchange in the treatment of Goopasture's syndrome. Lancet 1976;1(7962):723-6. [1]], with a significant decrease of antibodies during large volume exchanges. In the 80s, several prospective studies began to estimate the efficiency of PE in other autoimmune diseases. The national registry of the Société Française d' Hémaphérèse, has collected the epidemiological and technical data of PE since 1985. This work analyses the evolution of the validated indications, between 1990 and 2005 in France.

Collapsing and non-collapsing focal segmental glomerulosclerosis in kidney transplants

BACKGROUND

The aetiological and clinical associations of collapsing focal segmental glomerulosclerosis (cFSGS) following kidney transplantation (KTx) are poorly described. In this study, post-transplant cFSGS and non-collapsing FSGS (ncFSGS) were compared in recent KTx recipients. Evidence for intragraft viral infection was sought.

METHODS

Twenty-nine cases of post-KTx FSGS were identified and classified as cFSGS (n = 10) or ncFSGS (n = 19). Biopsies were scored using Banff '97 criteria and subjected to in situ hybridization (ISH) for parvovirus B19 (pvB19), simian virus 40 (SV40) and BK virus (BKV).

RESULTS

cFSGS and ncFSGS patients were comparable for age, gender, weight, delayed function, human leucocyte antigen (HLA) matching, acute rejection and median time to diagnosis. Deceased donor source was more common among cFSGS cases (70 vs 32%, P = 0.05). FSGS was recurrent in 2/10 cFSGS cases compared with 8/19 ncFSGS (P = NS). cFSGS was associated with more proteinuria (11.9 vs 7.2 g/day, P = 0.05) and higher serum creatinine (4.2 vs 1.9 mg/dl, P = 0.0001) at diagnosis. Plasmapheresis was used in two out of 10 cFSGS and seven out of 19 ncFSGS cases with treatment response in 0 of two and three of seven, respectively. Graft loss was more rapid with cFSGS compared with ncFSGS (P = 0.02). Histologically, cFSGS was associated with more severe chronic vascular abnormalities. All biopsies were negative for pvB19, SV40 and BKV by ISH.

CONCLUSIONS

cFSGS following KTx presents with higher proteinuria, diminished renal function, more severe vascular disease and higher rate of graft loss compared with the non-collapsing form. There was no evidence for infection by pvB19 or polyomaviruses.