Glomerulonephritis After Renal Transplatation in South Asia - Single Center Experience Over 5 Decades

Background

With significant advances in the understanding of transplant immunology and a reduction in rejection rates, significant improvements in kidney allograft survival have been seen. The problem of recurrent and denovo glomerular diseases after transplantation affecting graft outcomes remains and is poorly characterized. This study aimed to analyze the incidence, characteristics, and outcomes of glomerulonephritis (GN) after kidney transplant in the Indian subcontinent.

Materials and Methods

Data on patients who underwent kidney transplants in our hospital from 1971 to 2018 was analyzed. Patients who had biopsy proven glomerulonephritis after transplant were included in the study. Demographic factors, characteristics of glomerulonephritis after transplant, and patient and graft outcomes were studied.

Results

Post-transplant glomerulonephritis was seen in 177 out of 3630 (4.8%) patients. IgA nephropathy (IgAN) was the most common type, followed by focal segmental glomerulosclerosis (FSGS) and thrombotic microangiopathy (TMA). Patients with IgAN and FSGS were younger, and native kidney disease was unknown in the majority (70% in IgAN and 40% in FSGS). Glomerulonephritis was the most common cause of graft loss. A serum creatinine level of ≥2 mg/dL at 1 year post-transplant was significantly associated with the risk of death and graft loss. In addition, the occurrence of glomerulonephritis within a year of transplant and cytomegalovirus (CMV) infection were found to be significant risk factors for death and graft loss, respectively.

Conclusion

Post transplant glomerulonephritis can significantly impact patient and graft outcomes. Understanding its etiology and pathogenesis is crucial to enabling its prevention and management and improving the outcomes of kidney transplantation.

Clinical course and outcome of adult patients with primary focal segmental glomerulosclerosis with kidney function loss on presentation

BACKGROUND

Kidney function loss or renal insufficiency indicated by elevated creatinine levels and/or an estimated glomerular filtration rate (eGFR) < 60 mL/minute/1.73 m² at presentation in patients with primary focal segmental glomerulosclerosis (FSGS) is commonly seen as a poor prognostic marker for kidney survival. However, a pre>vious study from our center suggested this may be due to hemodynamic factors.

AIM

To observe the clinical and biochemical parameters, treatment response, kidney survival, and overall outcomes of adult patients with primary FSGS presenting with kidney function insufficiency.

METHODS

This retrospective observational study was conducted at the Department of Nephrology, Sindh Institute of Urology and Transplantation, Karachi, Pakistan, from January 1995 to December 2017. During this period, 401 biopsy-proven primary FSGS patients were identified, of which 98 (24.4%) presented with kidney function loss or renal insufficiency defined as eGFR < 60 mL/minute/1.73 m² at presentation and were studied in detail.

RESULTS

Among the 98 patients with renal function loss on presentation, the mean age was 30.9 years ± 13.6 years with a male-to-female ratio of 2.5:1. The mean serum creatinine level was 2.2 mg/dL ± 1.3 mg/dL and mean eGFR 37.1 mL/minute/1.73 m2 ± 12.8 mL/minute/1.73 m2. The mean 24-hour urinary protein excretion was 5.9 g/day ± 4.0 g/day, and the mean serum albumin was 2.1 g/dL ± 1.0 g/dL (median: 1.5 g/dL). The mean systolic blood pressure (BP) was 132.7 mmHg ± 19.8 mmHg, and the mean diastolic BP was 87.4 mmHg ± 12.7 mmHg. Steroid treatment was given to 81 (82.6%) of 98 patients for an average duration of 19.9 weeks ± 14.4 weeks, with a mean total steroid dose of 4.4 g ± 1.5 g. Treatment response showed that 20 (24.6%) patients achieved complete remission, 9 (11.1%) achieved partial remission, and 52 (64.1%) did not respond. The baseline eGFR was significantly lower in the non-responsive group (P = 0.006). The distribution of FSGS variants was also significantly different among steroid-responsive and non-responsive groups (P = 0.012).

CONCLUSION

Renal function loss in FSGS patients at presentation does not necessarily indicate irreversible kidney function loss and a significant number of patients respond to appropriate treatment of the underlying disease.

A new index for the outcome of focal segmental glomerulosclerosis

Focal segmental glomerulosclerosis (FSGS) is a common pathological form of nephrotic syndrome. This study analyzed the value of pathological lesions and clinical prognosis of different segmental glomerulosclerosis ratios in FSGS. Two hundred and six FSGS patients were collected from Dec 2013 to Apr 2016. The patients were divided into two groups according to the proportion of glomerular segmental sclerosis: F1 (SSR ≤ 15%, n = 133) and F2 (SSR > 15%, n = 73). The clinical and pathological data were recorded and analyzed, and statistical differences were observed between the serum uric acid level and the percentage of chronic renal failure. The pathological results showed significant differences in interstitial fibrosis and tubular atrophy (IFTA), degree of mesangial hyperplasia, vascular lesions, synaptopodin intensity, and foot process effacement between the two groups. Multivariate logistic regression analysis showed significant differences in creatinine (OR: 1.008) and F2 group (OR: 1.19). In all patients, the prognoses of urine protein and serum creatinine levels were statistically different. Multivariate Cox regression analysis revealed that F2 (hazard ratio: 2.306, 95% CI 1.022-5.207) was associated with a risk of ESRD (end stage renal disease). The proportion of segmental glomerulosclerosis provides a guiding value in the pathological diagnosis and clinical prognosis of FSGS.

Epidemiology and Outcomes of Glomerular Diseases in Low- and Middle-Income Countries

Glomerular diseases account for a significant proportion of chronic kidney disease in low-income and middle-income countries (LMICs). The epidemiology of glomerulonephritis is characterized inadequately in LMICs, largely owing to unavailable nephropathology services or uncertainty of the safety of the kidney biopsy procedure. In contrast to high-income countries where IgA nephropathy is the dominant primary glomerular disease, focal segmental glomerulosclerosis is common in large populations across Latin America, Africa, Middle East, and South East Asia, while IgA nephropathy is common in Chinese populations. Despite having a high prevalence of known genetic and viral risk factors that trigger focal segmental glomerulosclerosis, membranoproliferative glomerulonephritis also is common in adults and children in some African countries. Treatment of glomerular diseases in adults and children in LMICs largely is dependent on corticosteroids in combination with other immunosuppressive therapy, which often is cyclophosphamide because of its ready availability and low cost of treatment, despite significant adverse effects. Partial and/or complete remission status reported from studies of glomerular disease subtypes vary across LMIC regions, with high rates of kidney failure, mortality, and disease, and treatment complications often reported. Improving the availability of nephropathology services and ensuring availability of specific therapies are key measures to improving glomerular disease outcomes in LMICs.

Efficacy and Safety of Immunosuppressive Therapy in Primary Focal Segmental Glomerulosclerosis: A Systematic Review and Meta-analysis

Rationale & Objective

Focal segmental glomerulosclerosis (FSGS) is a rare condition that can lead to kidney function decline and chronic kidney failure. Immunosuppressants are used to treat primary FSGS. However, their efficacy and safety in FSGS are not clearly established. We assessed current knowledge on clinical effectiveness and safety of immunosuppressants for primary FSGS.

Study Design

Systematic review of randomized controlled trials, interventional nonrandomized controlled trials, observational studies, retrospective studies, and registries.

Setting & Participants

Patients with primary and genetic FSGS.

Selection Criteria for Studies

Medline, EMBASE, and the Cochrane Central Register of Controlled Trials were searched for English-language, primary-FSGS studies from inception to 2019. Clinical outcomes were changes from baseline in proteinuria, kidney function, and kidney survival.

Data Extraction

2 investigators independently screened studies and extracted data.

Analytical Approach

Study results were summarized using random-effects models either as ratios of means between follow-up and baseline measurements or as HRs.

Results

We included 98 articles. Substantial heterogeneity was observed in patient baseline characteristics and study designs. Most studies assessed treatment with corticosteroids alone or combined with other drugs, mainly immunosuppressants. Patients treated with immunosuppressants showed reduced proteinuria (14 studies; ratio of means, 0.36; 95% CI, 0.20-0.47), decreased creatinine clearance (mean difference, −25.03; 95% CI, −59.33 to −9.27) and (significantly) lower estimated glomerular filtration rates (mean difference, −7.61 mL/min/1.73 m²; 95% CI, −14.98 to 0.25 mL/min/1.73 m²). Immunosuppressant therapy had an uncertain effect on reducing the chronic kidney failure risk. Hypertension and infections were the most commonly reported adverse events.

Limitations

Heterogeneity in study designs, patient populations, and treatment regimens; no access to individual patient–level data.

Conclusions

This systematic review supports proteinuria reduction with immunosuppressant therapy in primary FSGS over varying follow-up periods. The effects of immunosuppressants on kidney survival remain uncertain. This review underscores the need for better-designed and adequately controlled studies to assess immunosuppressant therapy in patients with primary FSGS.

Efficacy and Safety of ACE Inhibitor and Angiotensin Receptor Blocker Therapies in Primary Focal Segmental Glomerulosclerosis Treatment: A Systematic Review and Meta-analysis

Rationale and Objective

Angiotensin-converting enzyme inhibitor or angiotensin receptor blocker therapy (renin-angiotensin-aldosterone system [RAAS] inhibitor) to control proteinuria in primary and genetic focal segmental glomerulosclerosis (FSGS) follows guidelines based on other proteinuria-related kidney diseases. There is no consensus on the efficacy and safety of RAAS inhibitor therapies in primary and genetic FSGS. This systematic review assessed the effects of RAAS inhibitor therapy on kidney outcomes in these patients.

Study Design

Systematic review of randomized controlled trials, interventional nonrandomized studies, observational studies, and retrospective studies.

Setting & Study Populations

Patients with primary and genetic FSGS.

Selection Criteria for Studies

PubMed, Cochrane Library, and Embase.

Data Extraction

2 investigators independently screened studies and extracted data.

Analytical Approach

Results were summarized as the ratio of means (ROM) between baseline and follow-up measurements or as the hazard ratio using random-effects models.

Results

30 publications were selected; 5 were controlled trials (4 randomized controlled trials). 8 assessed RAAS inhibitor monotherapy, while the rest studied RAAS inhibitors in combination with other drugs, mainly immunosuppressants. On average, a 32% proteinuria reduction (ROM, 0.68; 95% CI, 0.47-0.98) and no change in creatinine clearance (ROM, 0.95; 95% CI, 0.77-1.16) from baseline to the last reported follow-up was observed in patients treated with RAAS inhibitor monotherapy. When a RAAS inhibitor was combined with other drugs, a 72% proteinuria reduction was observed from baseline to the last reported follow-up (ROM, 0.24; 95% CI, 0.08-0.75). The published data did not allow for the assessment of the effects of RAAS inhibitor monotherapy on estimated glomerular filtration rate and end-stage kidney disease risks.

Limitations

Large study heterogeneity in design, patient populations, and treatment regimens. No access to individual patient-level data.

Conclusions

This review supports the tendency to observe a proteinuria reduction with RAAS inhibitors in patients with primary FSGS. RAAS inhibitor monotherapy was associated with maintained kidney function, as shown by no change in creatinine clearance. Strong evidence to quantify the effects of RAAS inhibitor monotherapy on end-stage kidney disease and glomerular filtration rate was lacking. Larger, well-designed clinical trials are needed to better understand the effects of RAAS inhibitors on primary FSGS.

Focal segmental glomerulosclerosis histologic variants and renal outcomes based on nephrotic syndrome, immunosuppression, and proteinuria remission

BACKGROUND

The associations of focal segmental glomerulosclerosis (FSGS) histologic variants with renal outcomes have rarely been investigated comprehensively by clinically relevant subgroups in this modern age.

METHODS

Data on 304 (173 nephrotic and 131 non-nephrotic) patients with biopsy-confirmed FSGS from 2010 to 2013 were analyzed using the Japanese nationwide renal biopsy registry. The primary outcome was a composite of a 30% decline in estimated glomerular filtration rate or progression to end stage kidney disease 5 years from the biopsy. We compared outcomes of FSGS variants according to the Columbia classification using survival analyses. Subgroup analyses were performed based on nephrotic syndrome (NS), immunosuppression, and proteinuria remission (PR, proteinuria <0.3 g/day) during follow-up. Additionally, associations of NS, immunosuppression, and PR with outcomes were examined for each variant.

RESULTS

The distribution of variants was 48% (n = 145) FSGS not otherwise specified (NOS), 19% (n = 57) tip, 15% (n = 47) perihilar, 13% (n = 40) cellular, and 5% (n = 15) collapsing. The outcome event occurred in 87 patients (29%). No significant differences in the outcome were found among the variants. Subgroup analyses yielded similar results. However, there was a trend toward improved outcome in patients with PR irrespective of variants (hazard ratio adjusted for histologic variant and potential confounders [adjusted HR]: 0.19 [95% confidence interval (CI), 0.10-0.34]). NS was marginally associated with better outcome compared with non-NS (adjusted HR: 0.50 [95% CI, 0.25-1.01].

CONCLUSIONS

FSGS variants alone might not have significant impacts on the renal outcome after 5 years, while PR could be predictive of improved renal prognosis for any variant. Specific strategies and interventions to achieve PR for each variant should be implemented for better renal outcomes.

Autoimmunity in Focal Segmental Glomerulosclerosis: A Long-Standing Yet Elusive Association

Focal segmental glomerulosclerosis (FSGS) is a histological term that describes a pathologic renal entity affecting both adults and children, with a wide array of possible underlying etiologies. Podocyte damage with scarring, the hallmark of this condition, leads to altered permeability of the glomerular barrier, which may result in massive proteinuria and relentless renal function deterioration. A definite cause of focal segmental glomerulosclerosis can be confirmed in a minority of cases, while most forms have been traditionally labeled as primary or idiopathic. Despite this definition, increasing evidence indicates that primary forms are a heterogenous group rather than a single disease entity: several circulating factors that may affect glomerular permeability have been proposed as potential culprits, and both humoral and cellular immunity have been implicated in the pathogenesis of the disease. Consistently, immunosuppressive drugs are considered as the cornerstone of treatment for primary focal segmental glomerulosclerosis, but response to these agents and long-term outcomes are highly variable. In this review we provide a summary of historical and recent advances on the pathogenesis of primary focal segmental glomerulosclerosis, focusing on implications for its differential diagnosis and treatment.

Immunoadsorption in nephrotic syndrome: Where are we now and where are we going from here?

Idiopathic nephrotic syndrome (INS) is characterized by three different entities, namely minimal change disease (MCD), focal segmental glomerulosclerosis (FSGS) and membranous nephropathy (MN). While there is an increasing understanding of primary MN with the discovery of antibodies directed against phospholipase A2 receptor (PLA2R Ab) and thrombospondin type 1 domain-containing 7A, circulatory factors causative of inducing MCD and FSGS remain in part elusive. Extracorporeal treatment forms (mostly plasma exchange) have been reserved for patients with either a disease course refractory to commonly prescribed immunosuppressive drugs or to patients with recurrence after kidney transplantation. There is a paucity of data supporting the use of immunoadsorption (IAS) in the management of MCD and MN and evidence to perform LDL-apheresis in the former is limited to reports from Japan. Treatment with IAS in primary FSGS has shown mixed responses, possibly biased by including treatment-resistant cases in the absence of genetic testing. In those with recurrence of the disease following kidney transplantation, IAS has shown high remission rates with an acceptable safety profile. There is a need to compare IAS to plasma exchange (PLEX) in this indication and due to a higher amount of plasma processed during one session, IAS may have advantages over PLEX. Removal of PLA2R Ab by IAS is currently being tested in a phase II clinical trial. More clinical trials in a prospective and randomized fashion need to be designed to prove the concept that IAS may be a treatment option for INS. While PLEX is still the leading extracorporeal treatment form in these indications, this review aims to highlight the efficacy and safety of IAS in the management of INS.

Glucocorticoids in the treatment of patients with primary focal segmental glomerulosclerosis and moderate proteinuria

BACKGROUND

To compare the efficacy of glucocorticoids in primary focal segmental glomerulosclerosis (pFSGS) patients with moderate proteinuria. Registered at http://www.chictr.org.cn/ , study No. ChiCTR-OPN-17012789.

METHODS

pFSGS patients with urine protein between 1.0 and 3.5 g/24 h were recruited from 2006 to 2016. No decline in urine protein > 50% was observed after 2 months of run-in angiotensin-converting enzyme inhibitors/angiotensin-receptor blockers (ACEI/ARB) treatment. Patients were assigned to study group (glucocorticoids with ACEI/ARB) or control group (ACEI/ARB without glucocorticoids). Variables including 24-h urinary protein, serum albumin and serum creatinine during the trial were recorded. Remission was defined as proteinuria < 0.3 g/24 h or declined > 50%, and our composite end point as > 30% decrease of eGFR or eGFR < 30 ml/min.

RESULTS

A total of 102 patients were enrolled (study group N = 52, control group N = 50), and the median follow-up time was 36 (12-117) months without significant difference between groups. During the 12-month follow-up, the remission rate was significantly higher in study group [73.1 vs 50.0% (P = 0.01)], and the initial median response time was 3 months in the study group while 6 in the control group. The end point was reached by 22.2% cases in study group, and 42.0% in control. The medium survival times were study group 72 months and control 57 (P = 0.03). Minor adverse reactions were observed in 10 patients (study group N = 8, control group N = 2).

CONCLUSIONS

Additional glucocorticoids therapy is more efficacious compared to ACEI/ARB alone in the treatment of patients with pFSGS and moderate proteinuria.