Impact of the COVID-19 Pandemic on Kidney Diseases Requiring Renal Biopsy: A Single Center Observational Study

Essential role of kidney biopsy in diagnosing glomerular diseases amidst evolving biomarkers

The discussion on renal biopsies and biomarkers highlights the essential aspects of nephrology. Although novel diagnostic biomarkers are emerging, renal biopsy remains critical for accurate diagnosis and treatment owing to the lack of sufficiently validated biomarkers with high sensitivity and specificity. Puspitasari et al highlighted the significant changes in renal biopsy indications and histological outcomes before and after the coronavirus disease 2019 (COVID-19) pandemic, reflecting the complex interactions between clinical workflows, public health issues, and patient demographics. Although biomarkers are increasingly utilized in nephrology, their importance remains balanced with traditional practices. Advancements in precision medicine are exemplified by tests like plasma anti-phospholipase A2 receptor levels. However, the COVID-19 pandemic revealed significant vulnerabilities in nephrology services, emphasizing the necessity for adaptable and robust healthcare strategies to manage chronic conditions during global crises. In conclusion, while biomarkers are poised to assume a more prominent role in nephrology, the significance of renal biopsies and thorough histopathological analysis remains paramount in understanding complex disease processes and guiding personalized patient management. The ongoing integration of traditional diagnostic approaches with innovative biomarker strategies promises to improve patient care and long-term health outcomes.

The prevalence of immunoglobulin A nephropathy in the European Union and the impact of the COVID-19 pandemic: an estimation approach utilizing the kidney biopsy frequency

Background

Immunoglobulin A nephropathy (IgAN) is the most common type of primary glomerulonephritis, requiring a kidney biopsy for diagnosis. This study aimed to estimate the prevalence of primary IgAN within the European Union (EU) and investigate the potential impact of the coronavirus disease 2019 (COVID-19) pandemic on kidney biopsy rates and IgAN diagnosis frequency.

Methods

We conducted four comprehensive literature searches to identify data on the IgAN prevalence and incidence, native kidney biopsy rates and COVID-19 impact on these metrics. We calculated country-specific prevalence estimates based on a combination of published and modeled data, incorporating biopsy frequency and the Healthcare Access and Quality Index (HAQI). The EU IgAN prevalence was derived from country-specific prevalence estimates weighted by population size.

Results

The estimated prevalence of IgAN in the EU was 4.31 per 10 000 population, with large geographic variation among countries, ranging from 0.16 to 14.4 per 10 000 population. A strong correlation was observed between the IgAN incidence and biopsy rate (R2 = 0.96). Countries with a higher HAQI mostly exhibited higher biopsy rates and IgAN incidences. The COVID-19 pandemic resulted in a notable decrease in kidney biopsy rates for most European countries with available information in 2020 compared with both pre- and post-pandemic periods. However, the long-term implications of this reduction on biopsy rates and subsequent IgAN incidence remain to be determined.

Conclusion

Our findings confirm the rarity of IgAN, albeit the most common type of glomerulonephritis. They underscore a robust correlation between biopsy rates and IgAN incidence, influenced by healthcare access and quality. The COVID-19 pandemic's temporary suppression of biopsy rates in 2020 suggests potential delays in IgAN diagnosis, warranting further investigation into the long-term effects.

Kidney failure-related excess mortality during the first three years of the COVID-19 pandemic in the United States: a nation-wide, population-based analysis

BACKGROUND

The onset of the COVID-19 pandemic has had a detrimental impact on the healthcare system. Patients with kidney failure and related kidney disease are notably vulnerable to the COVID-19 pandemic. However, it remains unclear how mortality trends associated with kidney failure have evolved over the past three years. In this study, we investigated temporal trends in excess kidney failure-related mortality during the first three years of the pandemic in the United States.

METHODS

We aim to estimate time-varying excess kidney failure-related mortality, which is defined as the difference between observed mortality and expected mortality predicted by a Poisson log-linear regression model, in the United States (March 2020-March 2023).

RESULTS

Our findings revealed two distinct peaks in excess kidney failure-related mortality during the first year (March 2020-February 2021) and the second year (February 2021-March 2022), whereas a notable decline in excess mortality was observed in the third year (March 2022-March 2023). Additionally, disparities in mortality were evident among various demographic groups, including age, sex, racial/ethnic subgroups, and geographic regions. Across all age subgroups, an increase in kidney failure-related mortalities was observed, with individuals aged 85 years and above experiencing the most substantial relative increase, reaching 9595.8 per million persons (95% CI: 9438.8, 9752.9). Moreover, excess kidney failure-related mortalities were recorded at 510.3 per million persons (95% CI: 502.6, 517.9) and 721.8 per million persons (95% CI: 713.4, 730.1) for women and men, respectively. Notably, non-Hispanic Blacks exhibited the highest excess mortality within the racial/ethnic group, registering at 772.6 per million persons (95% CI: 756.3, 788.9).

CONCLUSIONS

Our study observed high levels of excess kidney failure-related mortality during the first two years of the pandemic, followed by a notable decline in the third year. This highlights the effectiveness of current policies and prevention measures implemented to mitigate the impact of the pandemic.

The SElf-Care After REnal Transplantation Study: A Retrospective Evaluation of a Home-Monitoring Program Implemented as Standard Care

After transplantation self-management is essential for graft survival and optimal quality of life. To address the need for home-based support in self-management, we implemented the "SelfCare after Renal Transplantation" (SeCReT) box, containing home-monitoring equipment combined with a smartphone application that was linked to the electronic patient records. This study investigated the uptake and continuation, protocol adherence, and subjective evaluation of this home-monitoring program. All "de novo" kidney recipients who received the SeCReT-box in the study period (Aug 2021-Dec 2022) were eligible for inclusion. Protocol adherence was defined as ≥75%. Subjective evaluation was assessed with a 5-item questionnaire. Of the 297 recipients transplanted, 178 participants (60%) were included in the analysis. Protocol adherence was 83%, 73%, 66%, and 57% respectively at 5, 10, 20, and 40 weeks of the protocol. With regard to continuation, 135 participants were still in the program at the end of the study period (75% retention rate). Regarding subjective evaluations, 82% evaluated the program positively, and 52% reported lower care needs due to home-monitoring. Results are positive among those who entered and continued the program. Qualitative research is needed on barriers to entering the program and facilitators of use in order to promote optimal implementation.

Kidney Biopsy Findings in Patients with SARS-CoV-2 Infection or After COVID-19 Vaccination

BACKGROUND

Emerging case series described a temporal association between severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination and de novo or relapsing kidney diseases. We aimed to further understand vaccination- and coronavirus disease 2019 (COVID-19)-associated kidney diseases.

METHODS

We present findings from native kidney biopsies of patients recently vaccinated against SARS-CoV-2 ( n =27) and those with COVID-19 ( n =15), reviewed at a single German center. Diagnoses were compared among all native kidney biopsies ( n =10,206) obtained between the prepandemic (2019), pandemic (2020), and vaccination periods (2021) to determine whether there was an increase in kidney diseases in the observed periods.

RESULTS

Biopsy indication was increased serum creatinine and/or new-onset proteinuria. Glomerulopathies (20/27, 74%) were more common than tubulointerstitial diseases in postvaccination patients, with necrotizing GN (8/27, 30%) and primary podocytopathies and other GN types (6/27, 22% each) the most common forms. Acute tubular injury was the most common kidney disease in patients with COVID-19, followed by thrombotic microangiopathy (TMA) and necrotizing GN. The postvaccination and COVID-19 infection groups had similar kidney function recovery rates (69% and 73%, respectively). Furthermore, the frequencies of necrotizing GN, pauci-immune GN, TMA, or primary podocytopathies at our center did not increase between 2019 and 2021.

CONCLUSIONS

We observed differences in entity frequencies between the SARS-CoV-2 vaccination or COVID-19 groups, with glomerulopathies being more common in patients after vaccination and tubulointerstitial diseases in patients with COVID-19. Cases of TMA were observed only in the COVID-19 group. We detected no increase in the frequency of necrotizing GN, TMA, or podocytopathies between 2019 and 2021.

CLINICAL TRIAL REGISTRY NAME AND REGISTRATION NUMBER

Kidney Histopathology After COVID-19 and SARS-CoV-2 Vaccination, NCT05043168.

PODCAST

This article contains a podcast at https://dts.podtrac.com/redirect.mp3/www.asn-online.org/media/podcast/CJASN/2023_05_08_CJN0000000000000106.mp3.

Impact of the COVID-19 pandemic on the kidney community: lessons learned and future directions

The coronavirus disease 2019 (COVID-19) pandemic has disproportionately affected patients with kidney disease, causing significant challenges in disease management, kidney research and trainee education. For patients, increased infection risk and disease severity, often complicated by acute kidney injury, have contributed to high mortality. Clinicians were faced with high clinical demands, resource shortages and novel ethical dilemmas in providing patient care. In this review, we address the impact of COVID-19 on the entire spectrum of kidney care, including acute kidney injury, chronic kidney disease, dialysis and transplantation, trainee education, disparities in health care, changes in health care policies, moral distress and the patient perspective. Based on current evidence, we provide a framework for the management and support of patients with kidney disease, infection mitigation strategies, resource allocation and support systems for the nephrology workforce.

Impact of COVID 19 pandemic on patients requiring renal biopsy

INTRODUCTION

The disruption of healthcare services in coronavirus disease (COVID)19 pandemic was widespread particularly due to lockdown curbs. This study was undertaken to see the effect of this pandemic on subjects requiring renal biopsy.

MATERIALS AND METHOD

Renal biopsies performed during the COVID 19 pandemic between April 2020 and December 2020 (Group 1) were compared with those in pre-COVID period between June 2019 and February 2020 (Group 2). Indication of biopsies, syndromic diagnosis and all baseline laboratory characteristics were retrieved from the hospital records.

RESULTS

130 and 191 patients were biopsied in groups 1 and 2, respectively. Patients in group 1 were younger compared with group 2 (32.55 ± 15.60 and 36.37 ± 16.96 years, respectively, p value 0.038). The mean serum creatinine value in group 1 was significantly higher than in group 2 (3.21 ± 2.08 and 2.68 ± 2.02 mg/dl respectively, p value: 0.023). Group 1 comprises a significantly higher percentage of rapidly progressive renal failure patients (RPRF) (39.3 vs 28, p value 0.046). A higher percentage of nephrotics was biopsied in group 2 vs group 1 (46.9 vs 30.4 respectively, p value 0.008). The treatment protocol remained similar in both the groups. Evaluation of the transplant biopsies revealed a nonsignificant higher number of rejections in group 1 (11 out of 18) as compared to group 2 (5 out of 16), p value 0.100. Combined rejection saw a lesser use of rATG in group 1.

CONCLUSION

COVID pandemic induced restrictive measures could have led to selective high risk patients with RPRF as presumptive diagnosis and higher creatinine values getting biopsied. Higher rejections were noticed in transplant recipients pointing towards the need of establishing a more efficient support system for managing such patients.

Increased Rates of Supplement-Associated Oxalate Nephropathy During COVID-19 Pandemic

Introduction

Causes of secondary oxalate nephropathy include enteric dysfunction and excessive intake of oxalate or oxalate precursors. During the COVID-19 pandemic, there has been a dramatic rise in sales of supplements and vitamin C, during which time we observed an apparent increase in the proportion of ingestion-associated oxalate nephropathy.

Methods

We retrospectively reviewed secondary oxalate nephropathy and compared pre-pandemic (2018–2019) and pandemic (2020–early 2022) time periods.

Results

We identified 35 patients with kidney biopsy proven (30 native, 5 allograft) oxalate nephropathy at a single academic institution. Supplement-associated oxalate nephropathy comprised a significantly higher proportion of cases during COVID-19 pandemic compared with the preceding 2 years (44% vs. 0%, P = 0.002), and was associated with use of vitamin C, dietary changes, and supplements. Oxalate nephropathy in the kidney allograft, in contrast, remained associated with enteric hyperoxaluria, antibiotic use, and dehydration. Many patients had diabetes mellitus (57%), hypertension (40%) and/or pre-existing chronic kidney disease (CKD, 49%). Of 9 patients in which the potentially causative ingestion was identified and removed, 8 experienced improvement in kidney function.

Conclusion

There was a shift toward supplements rather than enteric hyperoxaluria as a leading cause of secondary oxalate nephropathy during the COVID-19 pandemic. Kidney outcomes are better than those observed for enteric hyperoxaluria, if the offending agent is identified and removed.

Urinary Tract Virome as an Urgent Target for Metagenomics

Virome—a part of a microbiome—is a term used to describe all viruses found in the specific organism or system. Recently, as new technologies emerged, it has been confirmed that kidneys and the lower urinary tract are colonized not only by the previously described viruses, but also completely novel species. Viruses can be both pathogenic and protective, as they often carry important virulence factors, while at the same time represent anti-inflammatory functions. This paper aims to show and compare the viral species detected in various, specific clinical conditions. Because of the unique characteristics of viruses, new sequencing techniques and databases had to be developed to conduct research on the urinary virome. The dynamic development of research on the human microbiome suggests that the detailed studies on the urinary system virome will provide answers to many questions about the risk factors for civilization, cancer, and autoimmune diseases.