COVID-19 and Glomerular Diseases.

COVID-19 is a systemic disease, and the kidney is one of the target organs of infection. Kidney injury is common and can occur in up to 40% of patients. Several glomerular diseases have been reported in association with COVID-19. Some are likely related to COVID-19 whereas many are likely coincidental. Glomerular diseases that are frequently reported in COVID-19 and have a plausible mechanistic explanation are likely to be related to COVID-19. In contrast, glomerular diseases that are seldom reported and have no known plausible mechanism, are likely to be unrelated. Collapsing glomerulopathy (CG) is by far the most prevalent. Its association with COVID-19, resembling HIV and CG, led to the newly proposed term "COVID-19 associated nephropathy" or "COVAN." High-risk APOL1 genotypes are the major risk factor in COVAN patients. Podocytopathy, membranous nephropathy (MN), pauci-immune crescentic glomerulonephritis (GN), and thrombotic microangiopathy (TMA) are also reported. In kidney allografts, CG remains the most common glomerular pathology. Patients typically present with acute kidney injury (AKI) or abnormal urinary findings at the time of or shortly after COVID-19 diagnosis. Treatment of glomerular disease in patients with COVID-19 is challenging. Providers should cautiously consider balancing risks and benefit of immunosuppression, particularly in patients with active diseases. Short-term outcomes vary but generally remain poor with high morbidity and mortality. Future study of long-term outcomes is needed to improve our understanding of glomerular disease associated with COVID-19.

A Case of COVID-Associated Nephropathy (COVAN).

Collapsing glomerulopathy is a variant of focal segmental glomerulosclerosis (FSGS) causing rapid renal failure. There has been an emergence of these cases among African American patients with COVID-19, especially those with the apolipoprotein L1 (APOL1) allele. We present a case of an African American patient with COVID-19 who tested positive for the APOL1 allele in the setting of acute renal deterioration. This provides a partial explanation for the increased burden of kidney failure in this population. As cases of COVID-19 persist, COVID-associated nephropathy (COVAN) should be suspected in patients with acute kidney injury and treatment tailored accordingly.

Coronavirus disease 2019-associated nephropathy in an African American patient: a case report and review of the literature.

BACKGROUND: Acute kidney injury is now recognized as a common complication of coronavirus disease 2019, affecting up to 46% of patients, with acute tubular injury as the most common etiology. Recently, we have seen an increase in cases of collapsing glomerulonephritis in patients with coronavirus disease 2019, also known as coronavirus disease 2019-associated nephropathy. It has been noted to be seen with a higher incidence in African American patients who are carriers of the APOL1 variant allele. CASE PRESENTATION: A 47-year-old African American male with a past medical history of asthma presented to the emergency department with complaints of intermittent chest pain, shortness of breath, and worsening confusion. On admission, he was found to be hemodynamically stable, but labs were significant for elevated creatinine and blood urea nitrogen, signifying acute kidney injury. He was admitted and taken for emergent dialysis. During his hospitalization, he was found to be positive for coronavirus disease 2019. Renal biopsy was done, which showed collapsing glomerulopathy, and the patient continues to require outpatient dialysis after discharge. CONCLUSION: Collapsing glomerulonephritis has emerged as a complication in patients with coronavirus disease 2019. This condition should be particularly suspected in African American patients who present with acute kidney injury, nephrotic-range proteinuria, and who are positive for coronavirus disease 2019. Current treatment options are limited to supportive treatment and renal replacement therapy. More clinical cases and trials are needed to better understand and improve therapeutic outcomes in these patients.

Kidney injury associated with COVID-19 infection and vaccine: A narrative review.

The respiratory tract is the main infection site for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), resulting in many admissions to intensive care centers in several countries. However, in addition to lung involvement, kidney injury caused by the novel coronavirus has proven to be a significant factor related to high morbidity and mortality, alarming experts worldwide. The number of deaths has drastically reduced with the advent of large-scale immunization, highlighting the importance of vaccination as the best way to combat the pandemic. Despite the undeniable efficacy of the vaccine, the renal side effects associated with its use deserve to be highlighted, especially the emergence or reactivation of glomerulopathies mentioned in some case reports. This study aimed to identify the main renal morphological findings correlated with COVID-19 infection and its vaccination, seeking to understand the pathophysiological mechanisms, main clinical features, and outcomes.

COVID-19 and HIV-associated Nephropathies: Double Whammy

The number of COVID-19-associated nephropathies (COVAN) rapidly increased before the fourth wave of the COVID-19 pandemic. Similarities and common lesions with the HIV-associated nephropathy (HIVAN) remarkably affect mostly African Americans positive for the APOL1 risk variants;therefore, these cases must be prioritized in new targeted clinical trials. Copyright © 2022, Bentham Science Publishers. All rights reserved.

A Rare Case of Granulomatous Interstitial Nephritis in a Patient With COVID-19.

Acute kidney injury (AKI) in patients with coronavirus disease 2019 (COVID-19) is common, especially among severely ill patients. While acute tubular necrosis (ATN) is one of the most common findings in published kidney biopsy series for patients with COVID-19 infections, a number of glomerular pathologies have been described as well. Among glomerular pathologies in COVID-19, COVID-19-Associated Collapsing Glomerulopathy (COVAN) remains the most common pattern of injury. Patients with 2 high-risk APOL1 alleles appear to be at increased risk for COVAN, similar to other forms of collapsing glomerulopathy such as HIV-Associated Nephropathy. Acute interstitial nephritis (AIN) is a less common finding in patients with COVID-19 and reported cases have been mild. Reports of a subtype of AIN, granulomatous interstitial nephritis (GIN), among COVID-19 patients are extremely rare and have not been reported in association with COVAN. Here, we report a case of COVAN associated with severe GIN.

COVAN Leading to ESKD Despite Minimal COVID Symptoms.

We report a case of dialysis dependence in a patient with COVID-19-associated nephropathy (COVAN) who had minimal respiratory manifestations. A 25-year-old man with a history of multiple sclerosis in remission presented with mild dyspnea due to COVID-19 pneumonia and was found to have rapidly worsening kidney function. He only required nasal cannula and was able to be weaned off within a few days. Despite having only mild respiratory disease, his kidney function worsened and urgent hemodialysis was started for hyperkalemia and uremic encephalopathy. Kidney biopsy demonstrated collapsing glomerulopathy due to COVID-19 with moderate interstitial fibrosis and tubular atrophy. His kidney function did not recover, and he unfortunately now has been dependent on hemodialysis for over 3 months. Multiple case reports have described COVAN causing dialysis dependence, but to our knowledge this is the first reported case of COVAN causing dialysis dependence in a patient with such mild respiratory disease. Currently the indications for intensive COVID-19 therapies are based on oxygen requirements. This case demonstrates that the oxygen requirement may not fully reflect the severity of COVID-19 and raises the question of whether these therapies should be considered in patients with COVAN.

Collapsing Focal Segmental Glomerulosclerosis in Viral Infections.

Collapsing glomerulopathy represents a special variant of the proteinuric kidney disease focal segmental glomerulosclerosis (FSGS). Histologically, the collapsing form of FSGS (cFSGS) is characterized by segmental or global condensation and obliteration of glomerular capillaries, the appearance of hyperplastic and hypertrophic podocytes and severe tubulointerstitial damage. Clinically, cFSGS patients present with acute kidney injury, nephrotic-range proteinuria and are at a high risk of rapid progression to irreversible kidney failure. cFSGS can be attributed to numerous etiologies, namely, viral infections like HIV, cytomegalovirus, Epstein-Barr-Virus, and parvovirus B19 and also drugs and severe ischemia. Risk variants of the APOL1 gene, predominantly found in people of African descent, increase the risk of developing cFSGS. Patients infected with the new Corona-Virus SARS-CoV-2 display an increased rate of acute kidney injury (AKI) in severe cases of COVID-19. Besides hemodynamic instability, cytokine mediated injury and direct viral entry and infection of renal epithelial cells contributing to AKI, there are emerging reports of cFSGS associated with SARS-CoV-2 infection in patients of mainly African ethnicity. The pathogenesis of cFSGS is proposed to be linked with direct viral infection of podocytes, as described for HIV-associated glomerulopathy. Nevertheless, there is growing evidence that the systemic inflammatory cascade, activated in acute viral infections like COVID-19, is a major contributor to the impairment of basic cellular functions in podocytes. This mini review will summarize the current knowledge on cFSGS associated with viral infections with a special focus on the influence of systemic immune responses and potential mechanisms propagating the development of cFSGS.

Pathology of COVID-19-associated acute kidney injury.

Acute kidney injury (AKI) is common among hospitalized patients with coronavirus disease 2019 (COVID-19), with the occurrence of AKI ranging from 0.5% to 80%. An improved knowledge of the pathology of AKI in COVID-19 is crucial to mitigate and manage AKI and to improve the survival of patients who develop AKI during COVID-19. In this review, we summarize the published cases and case series of various kidney pathologies seen with COVID-19. Both live kidney biopsies and autopsy series suggest acute tubular injury as the most commonly encountered pathology. Collapsing glomerulopathy and thrombotic microangiopathy are other encountered pathologies noted in both live and autopsy tissues. Other rare findings such as anti-neutrophil cytoplasmic antibody vasculitis, anti-glomerular basement membrane disease and podocytopathies have been reported. Although direct viral infection of the kidney is possible, it is certainly not a common or even widespread finding reported at the time of this writing (November 2020).

COVID-19 Pandemic: Is Africa Different?

COVID-19 has now spread to all the continents of the world with the possible exception of Antarctica. However, Africa appears different when compared with all the other continents. The absence of exponential growth and the low mortality rates contrary to that experienced in other continents, and contrary to the projections for Africa by various agencies, including the World Health Organization (WHO) has been a puzzle to many. Although Africa is the second most populous continent with an estimated 17.2% of the world's population, the continent accounts for only 5% of the total cases and 3% of the mortality. Mortality for the whole of Africa remains at a reported 19,726 as at August 01, 2020. The onset of the pandemic was later, the rate of rise has been slower and the severity of illness and case fatality rates have been lower in comparison to other continents. In addition, contrary to what had been documented in other continents, the occurrence of the renal complications in these patients also appeared to be much lower. This report documents the striking differences between the continents and within the continent of Africa itself and then attempts to explain the reasons for these differences. It is hoped that information presented in this review will help policymakers in the fight to contain the pandemic, particularly within Africa with its resource-constrained health care systems.