Renal Histopathological Changes in Coronavirus Disease 2019 Patients: A Systematic Review and Meta-analysis of Individual Patient Data.

The major targets of coronavirus disease 2019 (COVID-19) are the respiratory and immune systems. However, a significant proportion of hospitalized patients had kidney dysfunction. The histopathological surveys have principally focused on respiratory, hematopoietic, and immune systems, whereas histopathologic data of kidney injury are lacking. Our study aimed to summarize the renal histopathological findings in COVID-19 from the published case report and case series. We conducted a systematic searching of databases such as MEDLINE, EMBASE, and Cochrane Library for published reports of COVID-19 patients with renal histopathological changes from autopsy studies and from "for cause" indication biopsies. Included in our study are case reports and case series with extractable quantitative data on patient demographics such as age, sex, ethnicity, as well as data on renal function tests, their comorbidities, and biopsy to study the histopathological changes. Data were analyzed with Microsoft Excel. To evaluate the methodological quality, we chose the framework for appraisal, synthesis, and application of evidence suggested by Murad et al. Systematic searches of literature found 31 studies that fulfilled the eligibility criteria. These studies included a total of 139 cases, where individual case details including clinical and histopathological findings were available. The median age of the cases was 62 years with a male:female ratio of 2.5:1. Associated comorbidities were noted in 78.4% of cases. The majority of the cases had renal dysfunction with proteinuria which was documented in more than two-thirds of the cases. The histopathological findings observed the frequent tubular involvement manifested by acute tubular injury. Regarding glomerular pathology, collapsing glomerulopathy emerged as a distinct lesion in these patients and was noted among 46.8% of cases with glomerular lesions. A small subset of cases (4.3%) had thrombotic microangiopathy. Collapsing glomerulopathy emerged as a hallmark of glomerular changes among COVID-19 patients. Tubular damage is common and is linked to multiple factors including ischemia, sepsis among others. In the form of thrombotic microangiopathy seen in a subset of patients, vascular damage hints toward the hyper-coagulable state associated with the infection. The demonstration of viral particles in renal tissue remains debatable and requires further study.

Atypical hemolytic uremic syndrome induced by SARS-CoV2 infection in infants with EXOSC3 mutation.

BACKGROUND: Atypical hemolytic uremic syndrome (aHUS) is a rare disease characterized by systemic thrombotic microangiopathy mainly in the kidneys and mostly due to genetic disorders leading to uncontrolled activation of the complement system. Severe complications of SARS-CoV2 infection are linked to microvascular injury and complement activation is suspected to play a role in the pathogenesis of endothelial cell damage in severe COVID-19. METHODS: We present the first two cases of aHUS triggered by SARS-CoV-2 infection in two unrelated infants with the same mutation in the RNA exosome gene EXOSC3. This mutation is known to cause pontocerebellar hypoplasia type 1b, an autosomal-recessive neurodegenerative disease. So far, no kidney involvement in affected persons was reported. RESULTS: As eculizumab treatment was unsuccessful and complement-mediated disorders were ruled out, we suppose that the atypical HUS in our two patients is not due to complement-mediated thrombotic microangiopathy but rather due to a dysfunction of the RNA exosome. CONCLUSIONS: The RNA exosome is crucial for the precise processing and degradation of nuclear and cytoplasmatic RNA. We suspect that the SARS-CoV-2 infection led to changes in RNA that could not be offset by the defective RNA exosome in our two patients. The accumulation/wrong processing of the viral RNA must have led to the endothelial cell damage resulting in aHUS. This would be a new - "RNA-induced" - mechanism of aHUS.

Thrombotic Microangiopathy, Antibody-Mediated Rejection, and Posterior Reversible Leukoencephalopathy Syndrome in a Liver Transplant Recipient: Interplay Between COVID-19 and Its Treatment Modalities.

The present COVID-19 pandemic is a cause for concern among solid-organ transplant recipients, who are generally at high risk for infection and for whom infection with COVID-19 carries additional risks for complications and mortality that are higher than the COVID-19-associated risks for the general population. We report the case of a liver transplant recipient who presented with COVID-19 and multiple complications. A 39-year-old woman with a liver transplant was diagnosed with COVID-19 within the first week after transplant surgery. Mycophenolate was withheld, and interferon ß was administered for management of COVID-19. She developed thrombotic thrombocytopenic purpura, acute antibody-mediated rejection, and posterior reversible leukoencephalopathy syndrome during hospitalization. All of these complications may be related to COVID-19 or its management modalities. We considered 3 possible causes for thrombotic thrombocytopenic purpura in this patient: the COVID-19 infection itself, immunosuppression treatment with cyclosporine, and treatment with interferon ß. Immunosuppression reduction and interferon treatment may result in antibody-mediated rejection. COVID-19, thrombotic thrombocytopenic purpura, and cyclosporine may play a combined role in the development of posterior reversible leukoencephalopathy syndrome. In conclusion, thrombotic thrombocytopenic purpura, antibody-mediated rejection, and posterior reversible leukoencephalopathy syndrome may represent a continuum of 3 thrombotic microangiopathy conditions fostered by interplay between the COVID-19 infection and the treatment modalities for COVID-19 management in this patient.

Evidence of thrombotic microangiopathy in children with SARS-CoV-2 across the spectrum of clinical presentations.

Most children with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection have mild or minimal disease, with a small proportion developing severe disease or multisystem inflammatory syndrome in children (MIS-C). Complement-mediated thrombotic microangiopathy (TMA) has been associated with SARS-CoV-2 infection in adults but has not been studied in the pediatric population. We hypothesized that complement activation plays an important role in SARS-CoV-2 infection in children and sought to understand if TMA was present in these patients. We enrolled 50 hospitalized pediatric patients with acute SARS-CoV-2 infection (n = 21, minimal coronavirus disease 2019 [COVID-19]; n = 11, severe COVID-19) or MIS-C (n = 18). As a biomarker of complement activation and TMA, soluble C5b9 (sC5b9, normal 247 ng/mL) was measured in plasma, and elevations were found in patients with minimal disease (median, 392 ng/mL; interquartile range [IQR], 244-622 ng/mL), severe disease (median, 646 ng/mL; IQR, 203-728 ng/mL), and MIS-C (median, 630 ng/mL; IQR, 359-932 ng/mL) compared with 26 healthy control subjects (median, 57 ng/mL; IQR, 9-163 ng/mL; P < .001). Higher sC5b9 levels were associated with higher serum creatinine (P = .01) but not age. Of the 19 patients for whom complete clinical criteria were available, 17 (89%) met criteria for TMA. A high proportion of tested children with SARS-CoV-2 infection had evidence of complement activation and met clinical and diagnostic criteria for TMA. Future studies are needed to determine if hospitalized children with SARS-CoV-2 should be screened for TMA, if TMA-directed management is helpful, and if there are any short- or long-term clinical consequences of complement activation and endothelial damage in children with COVID-19 or MIS-C.

COVID-19-Associated Systemic Thromboembolism: A Case Report and Review of the Literature.

INTRODUCTION: Coronavirus disease 2019 (COVID-19) is a pandemic that has affected >188 countries, involved >24 million people, and caused >840,000 deaths. COVID-19, in its severe form, presents as acute respiratory distress syndrome (ARDS), shock, and multiorgan failure. Thrombotic microangiopathy of the lungs and kidneys has been observed in these patients. Elevated D-dimer levels have been observed in people with serious COVID-19 illness, and this could be helpful in guiding treatment with anticoagulation in these patients. OBJECTIVE: To analyze the role of anticoagulation as a treatment modality for COVID-19. METHODS: We present the unique case of a COVID-19 patient who developed sepsis, ARDS, acute kidney injury, and deep-vein thrombosis (DVT), who was deteriorating clinically. She was treated with anticoagulation. RESULTS: There was rapid recovery after treatment with systemic anticoagulation. CONCLUSIONS: Systemic anticoagulation could prove to be essential in the treatment of CO-VID-19. Further studies are required to assess its role in improving long-term morbidity and mortality in these patients.

Ischemic-hemorrhagic stroke in patients with Covid-19. / Afectación cerebrovascular isquémico-hemorrágica en pacientes con covid-19.

Coronavirus associated severe acute respiratory syndrome (SARS-CoV-2) causes a worldwide syndrome called Covid-19 that has caused 5,940,441 infections and 362,813 deaths until May 2020. In moderate and severe stages of the infection a generalized swelling, cytokine storm and an increment of the heart damage biomarkers occur. In addition, a relation between Covid-19 and neurological symptoms have been suggested. The results of autopsies suggest thrombotic microangiopathy in multiple organs. We present 2 cases of patients infected with severe Covid-19 that were hospitalized in the Reanimation Unit that presented cerebrovascular symptoms and died afterwards. A high dose prophylaxis with antithrombotic medication is recommended in patients affected by moderate to severe Covid-19.

Mild Clinical Course of COVID-19 in 3 Patients Receiving Therapeutic Monoclonal Antibodies Targeting C5 Complement for Hematologic Disorders.

BACKGROUND Patients receiving immunosuppressive therapies might be more susceptible to COVID-19. Conversely, an exaggerated inflammatory response to the SARS-CoV-2 infection might be blunted by certain forms of immunosuppression, which could be protective. Indeed, there are data from animal models demonstrating that complement may be a part of the pathophysiology of coronavirus infections. There is also evidence from an autopsy series demonstrating complement deposition in the lungs of patients with COVID-19. This raises the question of whether patients on anti-complement therapy could be protected from COVID-19. CASE REPORT Case 1 is a 39-year-old woman with an approximately 20-year history of paroxysmal nocturnal hemoglobinuria (PNH), who had recently been switched from treatment with eculizumab to ravulizumab prior to SARS-CoV-2 infection. Case 2 is a 54-year-old woman with a cadaveric renal transplant for lupus nephritis, complicated by thrombotic microangiopathy, who was maintained on eculizumab, which she started several months before she developed the SARS-CoV-2 infection. Case 3 is a 60-year-old woman with a 14-year history of PNH, who had been treated with eculizumab since 2012, and was diagnosed with COVID-19 at the time of her scheduled infusion. All 3 patients had a relatively mild course of COVID-19. CONCLUSIONS We see no evidence of increased susceptibility to SARS-CoV-2 in these patients on anti-complement therapy, which might actually have accounted for the mild course of infection. The effect of anti-complement therapy on COVID-19 disease needs to be determined in clinical trials.

Endothelial injury and thrombotic microangiopathy in COVID-19: Treatment with the lectin-pathway inhibitor narsoplimab.

In COVID-19, acute respiratory distress syndrome (ARDS) and thrombotic events are frequent, life-threatening complications. Autopsies commonly show arterial thrombosis and severe endothelial damage. Endothelial damage, which can play an early and central pathogenic role in ARDS and thrombosis, activates the lectin pathway of complement. Mannan-binding lectin-associated serine protease-2 (MASP-2), the lectin pathway's effector enzyme, binds the nucleocapsid protein of severe acute respiratory syndrome-associated coronavirus-2 (SARS-CoV-2), resulting in complement activation and lung injury. Narsoplimab, a fully human immunoglobulin gamma 4 (IgG4) monoclonal antibody against MASP-2, inhibits lectin pathway activation and has anticoagulant effects. In this study, the first time a lectin-pathway inhibitor was used to treat COVID-19, six COVID-19 patients with ARDS requiring continuous positive airway pressure (CPAP) or intubation received narsoplimab under compassionate use. At baseline and during treatment, circulating endothelial cell (CEC) counts and serum levels of interleukin-6 (IL-6), interleukin-8 (IL-8), C-reactive protein (CRP) and lactate dehydrogenase (LDH) were assessed. Narsoplimab treatment was associated with rapid and sustained reduction of CEC and concurrent reduction of serum IL-6, IL-8, CRP and LDH. Narsoplimab was well tolerated; no adverse drug reactions were reported. Two control groups were used for retrospective comparison, both showing significantly higher mortality than the narsoplimab-treated group. All narsoplimab-treated patients recovered and survived. Narsoplimab may be an effective treatment for COVID-19 by reducing COVID-19-related endothelial cell damage and the resultant inflammation and thrombotic risk.

COVID-19 Pandemic and Pregnancy in Kidney Disease.

Coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is a rapidly spreading pandemic. Owing to changes in the immune system and respiratory physiology, pregnant women are vulnerable to severe viral pneumonia. We review the clinical course, pregnancy outcomes, and management of women with COVID-19 in pregnancy with a focus on those with kidney involvement. Current evidence does not show an increased risk of acquiring SARS-CoV-2 during pregnancy and the maternal course appears to be similar to nonpregnant patients. However, severe maternal disease can lead to complex management challenges and has shown to be associated with higher incidence of preterm and caesarean births. The risk of congenital infection with SARS-CoV-2 is not known. All neonates must be considered as high-risk contacts and should be screened at birth and isolated. Pregnant women should follow all measures to prevent SARS-CoV-2 exposure and this fear should not compromise antenatal care. Use of telemedicine, videoconferencing, and noninvasive fetal and maternal home monitoring devices should be encouraged. High-risk pregnant patients with comorbidities and COVID-19 require hospitalization and close monitoring. Pregnant women with COVID-19 and kidney disease are a high-risk group and should be managed by a multidisciplinary team approach including a nephrologist and neonatologist.