Renal Prognosis of COVID-19 Associated Nephropathy

Kidney damage associated with COVID-19: from the acute to the chronic phase

Severe acute respiratory syndrome coronavirus-2 (SARS-COV-2) infection is well established as a systemic disease including kidney damage. The entry point into the renal cell remains the angiotensin-converting enzyme 2 (ACE-2) receptor and the spectrum of renal lesions is broad, with a clear predominance of structural and functional tubular lesions. The most common form of glomerular injury is collapsing glomerulopathy (CG), which is strongly associated with apolipoprotein L1(APOL-1) risk variants. These acute lesions, which are secondary to the direct or indirect effects of SARS-CoV-2, can progress to chronicity and are specific to long COVID-19 in the absence of any other cause. Residual inflammation associated with SARS-CoV-2 infection, in addition to acute kidney injury (AKI) as a transitional state with or without severe histological lesions, may be responsible for greater kidney function decline in mild-to-moderate COVID-19. This review discusses the evidence for renal histological markers of chronicity in COVID-19 patients and triggers of low-grade inflammation that may explain the decline in kidney function in the post-COVID-19 period.

Coronavirus Disease 2019 in Kidney Transplantation - A 2024 Update

The coronavirus disease 2019 (COVID-19) pandemic, caused by the severe acute respiratory syndrome coronavirus 2 has led to the death of about 7 million people worldwide. When infected, older individuals and those with diabetes, hypertension, cardiovascular disease, and compromised immune system are at higher risk for unfavorable outcomes. These comorbidities are prevalent in kidney transplant candidates and recipients making them inherently vulnerable to severe acute respiratory syndrome coronavirus 2 infection, hence, the significant burden the pandemic has exerted on kidney transplant programs. With the swift discovery and wide-scale availability of vaccines and therapeutics against severe acute respiratory syndrome coronavirus 2, the pandemic is currently behind us allowing transplant programs to relieve their restrictions and resume normal pre-COVID-19 operations. In the aftermath of the pandemic, we discuss the implications for immunosuppression and vaccination, COVID-19-induced kidney injury phenotypes and long COVID-19 symptoms. We also discuss some of the operational aspects the pandemic brought about - mainly the utilization of telemedicine - that are now here to stay.

An Update on Viral Infection-Associated Collapsing Glomerulopathy

The COVID-19 era has been a reminder to clinicians around the world of the important role that viral infections play in promoting glomerular disease. Several viral infections including human immunodeficiency virus (HIV), severe acute respiratory syndrome coronavirus 2, Epstein-Barr virus, cytomegalovirus, and parvovirus B19 can cause podocyte injury and present with a collapsing glomerulopathy (CG) variant of focal segmental glomerulosclerosis or minimal change disease. CG associated with COVID-19 has been termed COVID-19-associated nephropathy due to its striking resemblance to HIV-associated nephropathy. Host susceptibility is a major determinant of viral infection-associated CG, and the presence of two APOL1 risk variants explains most of the racial predilection to viral-associated CG observed in individuals of African ancestry. Interactions between APOL1 risk variants, viral genes, and the systemic inflammatory response to viral infection all contribute to kidney injury. This review will summarize our current knowledge of viral infection-associated CG, focusing primarily on the clinical presentation, histological features, mechanisms, and disease course of HIV-associated nephropathy and COVID-19-associated nephropathy.

Understanding the effects of COVID-19 on patients with diabetic nephropathy: a systematic review

Background

Diabetic nephropathy is one of the consequences of diabetes mellitus that causes a continuous decline in the eGFR. After the COVID-19 pandemic, studies have shown that patients with diabetic nephropathy who had contracted COVID-19 have higher rates of morbidity and disease progression. The aim of this study was to systematically review the literature to determine and understand the effects and complications of SARS-CoV-2 on patients with diabetic nephropathy.

Materials and methods

The authors' research protocol encompassed the study selection process, search strategy, inclusion/exclusion criteria, and a data extraction plan. A systematic review was conducted by a team of five reviewers, with an additional reviewer assigned to address any discrepancies. To ensure comprehensive coverage, the authors employed multiple search engines including PubMed, ResearchGate, ScienceDirect, SDL, Ovid, and Google Scholar.

Results

A total of 14 articles meeting the inclusion criteria revealed that COVID-19 directly affects the kidneys by utilizing ACE2 receptors for cell entry, which is significant because ACE2 receptors are widely expressed in the kidney.

Conclusion

COVID-19 affects kidney health, especially in individuals with diabetic nephropathy. The mechanisms include direct viral infection and immune-mediated injury. Early recognition and management are vital for improving the outcomes.

The changing landscape of HIV-associated kidney disease

The HIV epidemic has devastated millions of people globally, with approximately 40 million deaths since its start. The availability of antiretroviral therapy (ART) has transformed the prognosis of millions of individuals infected with HIV such that a diagnosis of HIV infection no longer automatically confers death. However, morbidity and mortality remain substantial among people living with HIV. HIV can directly infect the kidney to cause HIV-associated nephropathy (HIVAN) - a disease characterized by podocyte and tubular damage and associated with an increased risk of kidney failure. The reports of HIVAN occurring primarily in those of African ancestry led to the discovery of its association with APOL1 risk alleles. The advent of ART has led to a substantial decrease in the prevalence of HIVAN; however, reports have emerged of an increase in the prevalence of other kidney pathology, such as focal segmental glomerulosclerosis and pathological conditions associated with co-morbidities of ageing, such as hypertension and diabetes mellitus. Early initiation of ART also results in a longer cumulative exposure to medications, increasing the likelihood of nephrotoxicity. A substantial body of literature supports the use of kidney transplantation in people living with HIV, demonstrating significant survival benefits compared with that of people undergoing chronic dialysis, and similar long-term allograft and patient survival compared with that of HIV-negative kidney transplant recipients.

COVID-19-Associated Nephropathy: A Devastating Complication

With the rapid emergence and prevalence of SARS-CoV-2 worldwide, cases of COVID-19-associated nephropathy (COVAN) from collapsing focal segmental glomerulosclerosis (cFSGS) have been reported, and the associations between the two are actively being studied. Creating appropriate treatment guidelines for COVAN requires further understanding of the pathophysiology of this type of kidney injury. This case report outlines the case of a 77-year-old patient admitted to the hospital for COVID-19 infection with a subsequent renal biopsy indicating cFSGS, adding to the data exploring the relationship between COVID-19 infections, cFSGS and the associated risk factors. Current guidelines on the treatment of COVAN are similar to those of other causes of cFSGS but continue to have poor outcomes and resistance to treatments. Further research needs to be done on both the clinical assessment and pathophysiology of COVAN to provide timely and life-saving interventions.

FSGS and COVID-19 in Non-African American Patients

Collapsing Focal Segmental Glomerulosclerosis (FSGS) has been reported relatively frequently in African American (AA) patients with coronavirus disease 2019 (COVID-19), and it is associated almost always with Apolipoprotein L gen 1 (APOL1) high-risk variants. We reviewed the published literature from April 2020 to November 2022 searching for non-African American (non-AA) patients with FSGS associated with COVID-19 (eight White patients, six Hispanic patients, three Asian patients, one Indian patient, and one Asian Indian patient). The following histologic patterns were found: collapsing (n=11), not otherwise specified (n=5), tip (n=2), and perihilar (n=1). Fifteen of the 19 patients had AKI. The APOL1 genotype was reported in only six of the 19 non-AA patients. Three of them (two Hispanic patients and one White patient) with collapsing FSGS had high-risk APOL1 variants. The other three patients (two White patients and one Hispanic patient with the collapsing variant, tip variant, and not otherwise specified) had low-risk APOL1 variants. Among 53 African American patients with collapsing FSGS associated with COVID-19, 48 had high-risk APOL1 variants and five had low-risk APOL1 variants. We conclude that in non-AA patients, FSGS is a rare complication of COVID-19. FSGS associated with COVID-19 can occur rarely with low-risk APOL1 variants in non-AA and AA patients. Non-AA patients reported to be associated with high-risk APOL1 variants possibly reflect inaccuracy of self-reported race with AA admixture because of unknown ancestry. Given the importance of APOL1 in the pathogenesis of FSGS associated with viral infection and to avoid racial bias, it seems appropriate that APOL1 testing be considered in patients with FSGS associated with COVID-19, regardless of self-reported race.