Strategies to prevent SARS-CoV-2 transmission in hemodialysis centres across Europe - Lessons for the future

Background

Early reports on the pandemic nature of COVID-19 directed the nephrology community to develop infection prevention and control guidance. We aimed to make an inventory of strategies that dialysis centres followed to prevent infection with COVID-19 in the first pandemic wave.

Methods

We analyzed IPC measures taken by hemodialysis centres treating patients presenting with COVID-19 between March 1, 2020 and July 31, 2020 and that completed the European Renal Association COVID-19 Database centre questionnaire. Additionally, we made an inventory of guidelines published in European countries to prevent spread of SARS-CoV-2 in dialysis centres.

Results

Data from 73 dialysis units located in and bordering Europe were analyzed. All participating centres implemented IPC measures to mitigate the impact of SARS-CoV-2 during the first pandemic wave. Measures mentioned most often included triage with questions before entering the dialysis ward, measuring body temperature, hand disinfection, masking for all patients and staff, and personal protective equipment for staff members. These measures were also recommended in most of the 14 guidelines that were identified in the inventory of national guidelines and were also scored as being among the most important measures by the authors of this paper. Heterogeneity existed between centres and national guidelines regarding the minimal distance between dialysis chairs and recommendations regarding isolation and cohorting.

Conclusions

Although variation existed, measures to prevent transmission of SARS-CoV-2 were relatively similar across centres and national guidelines. Further research is needed to assess causal relationships between measures taken and spread of SARS-CoV-2.

Idiopathic Membranous Nephropathy: Outline and Rationale of a Treatment Strategy

Idiopathic membranous nephropathy is a common cause of nephrotic syndrome. The treatment of patients with idiopathic membranous nephropathy is heavily debated. Based on literature data and our own experience, we propose a rational treatment strategy. Patients with renal insufficiency (serum creatinine level > 1.5 mg/dL [> 135 micromol/L]) are at greatest risk for the development of end-stage renal disease and should receive immunosuppressive therapy. In patients with normal renal function (serum creatinine level < 1.5 mg/dL [< 135 micromol/L]), risk for developing end-stage renal disease can be estimated by measuring urinary excretion of beta2-microglobulin or alpha1-microglobulin and immunoglobulin G. For low-risk patients, a wait-and-see policy is advised. High-risk patients likely benefit from immunosuppressive therapy. Currently, combinations of steroids with chlorambucil or cyclophosphamide are the best studied. We prefer cyclophosphamide in view of its fewer side effects. Cyclosporine may be an alternative option in patients with well-preserved renal function, although long-term data are lacking. Other immunosuppressive agents, such as mycophenolate mofetil or rituximab, currently are under study; however, data are insufficient to support their routine use.

Treatment-related changes in urinary excretion of high and low molecular weight proteins in patients with idiopathic membranous nephropathy and renal insufficiency

BACKGROUND

In patients with idiopathic membranous nephropathy, an increased urinary excretion of high (IgG) and low [beta(2)-microglobulin (beta(2)M), alpha(1)-microglobulin (alpha(1)M)] molecular weight proteins predicts prognosis and precedes renal insufficiency. We have studied the changes in the urinary excretion of these proteins in patients with idiopathic membranous nephropathy and renal insufficiency during and after treatment with cyclophosphamide and steroids, and investigated their value in predicting long-term outcome.

METHODS

Standardized measurements of urinary IgG, albumin, beta(2)M and alpha(1)M were performed at 0, 2, 6 and 12 months in 11 patients, at 12 months in 25 patients and in 17 of these last patients after 2-5 years.

RESULTS

We observed a rapid improvement of glomerular permselectivity and tubular protein reabsorption within 2 months after the start of therapy. Despite a partial remission of proteinuria within 12 months in most patients, evidence of tubulo-interstitial injury remained apparent. Neither absolute levels of urinary IgG, beta(2)M or alpha(1)M at baseline or at 12 months nor the percentage reduction between baseline and 12 months clearly predicted the occurrence of a remission or a relapse to nephrotic range proteinuria. In the case of a persistent stable remission, we observed a gradual decrease of urinary beta(2)M towards normal values.

CONCLUSIONS

In patients with idiopathic membranous nephropathy and renal insufficiency, treatment with cyclophosphamide and steroids resulted in an improvement of glomerular permeability and tubular proteinuria. Tubular proteinuria remained present for many years, even in patients with stable remission of proteinuria. Measurements of urinary proteins at 12 months after treatment start lacked predictive accuracy.

Efficacy of a second course of immunosuppressive therapy in patients with membranous nephropathy and persistent or relapsing disease activity

BACKGROUND

A single course of immunosuppressive treatment improves renal survival in patients with idiopathic membranous nephropathy (iMN) and renal insufficiency. However, not all patients respond and relapses occur within 5 years in 30% of patients. It is unknown if a second course of immunosuppressive therapy is effective in such patients.

METHODS

We have prospectively studied and evaluated the clinical course in 15 patients (14 male, one female; age: 52+/-12 years) with iMN who have received a repeated course of immunosuppressive therapy because of deteriorating renal function associated with relapsing or persistent nephrotic syndrome.

RESULTS

The first course of immunosuppression was started 8 months (range: 0-143 months) after renal biopsy and consisted of chlorambucil (n = 8) or cyclophosphamide (n = 7); the second course consisted of cyclophosphamide in all patients. The interval between the first and second course was 40 months (range: 7-112 months). Total follow-up was 110 months (range: 46-289 months). Renal function and proteinuria improved at least temporarily in all patients after the second course. During follow-up, an additional course of therapy was given in four patients. Status at the end of follow-up was complete remission (n = 2), partial remission (n = 8), persistent proteinuria (n = 3), end-stage renal disease (n = 1) and death (n = 1, due to cardiovascular disease while nephrotic). Renal survival was 86% at 5 and 10 years of follow-up. The repeated courses of immunosuppression have resulted in a gain of dialysis-free survival time of > or =93 months (range: 43-192 months).

CONCLUSIONS

Our results indicate that patients with iMN who do not respond well or relapse after a first course of immunosuppressive therapy and have renal insufficiency should be offered a second course of immunosuppression. Such a strategy maintains renal function in the majority of patients.

Cytotoxic therapy for membranous nephropathy and renal insufficiency: improved renal survival but high relapse rate

BACKGROUND

Patients with idiopathic membranous nephropathy (iMN) and renal insufficiency have a high risk for progression to end-stage renal disease (ESRD). In the short term, treatment with oral cyclophosphamide and steroids attenuates the deterioration of renal function in these patients; however, the long-term efficacy is unknown.

METHODS

We have studied prospectively 65 patients with iMN and renal insufficiency (serum creatinine >135 micromol/l) who were treated with oral cyclophosphamide (1.5-2.0 mg/kg/day for 12 months) and steroids (methylprednisolone pulses 3 x 1 g, i.v. at months 1, 3 and 5, and oral prednisone 0.5 mg/kg/48 h for 6 months).

RESULTS

Follow-up was 51 (5-132) months. Renal function temporarily improved or stabilized in all patients. A partial remission (PR) occurred in 56 patients followed by a complete remission (CR) in 17. During follow-up, 11 patients had relapsed (28% relapse rate after 5 years), of whom nine were re-treated because of renal function deterioration. At the end of follow-up, 16 patients were in CR, 31 in PR, eight had a persistent nephrotic syndrome, one had mild proteinuria, four had progressed to ESRD and five had died. Overall renal survival was 86% after 5 years and 74% after 7 years, compared with 32% after 5 and 7 years in a historical control group. Treatment-related complications occurred in two-thirds of patients, mainly consisting of bone marrow depression and infections. One patient has developed bladder cancer, another patient prostate cancer.

CONCLUSIONS

Renal survival is good if patients with iMN and renal insufficiency are treated with oral cyclophosphamide. However, side effects occur frequently and relapse rate is high during longer follow-up.