COVID-19 disease, caused by SARS-CoV-2 infection, has resulted in more than 15.5 million infections and 634,000 deaths worldwide. A recent study of hospitals in New York City, at the initial epicenter of the COVID-19 pandemic in the United States, reported that, during March 2020, 21% of patients hospitalized with confirmed COVID-19 died 1 . These findings are aligned with outcomes observed in the Mount Sinai Health System 2,3 . There are currently no curative or preventive therapies for COVID-19, highlighting the need to enhance current understanding of SARS-CoV-2 pathogenesis for the rational development of therapeutics.Recent studies have suggested that, in addition to direct viral damage, uncontrolled inflammation contributes to disease severity in 5 ). Consistent with this hypothesis, high levels of inflammatory markers, including C-reactive protein (CRP), ferritin and D-dimer, high neutrophil-to-lymphocyte ratio [6][7][8][9] and increased levels of inflammatory cytokines and chemokines 6,8-11 have been observed in patients with severe diseases. Pathogenic inflammation, also referred to as cytokine storm, shares similarities with what was previously seen in patients infected with other severe coronaviruses, including SARS-CoV and Middle East respiratory syndrome coronavirus 12 , and bears similarities to cytokine release syndrome (CRS) observed in patients with cancer treated with chimeric antigen receptor-modified (CAR) T cells 13 . Tocilizumab, an IL-6 receptor inhibitor, is a US Food and Drug Administration (FDA)-approved treatment for CRS in patients receiving CAR T cells 14 . Several single-center studies have used IL-6 inhibitors to treat patients with COVID-19 with some clinical benefits 15 and reported failures 14 . Beyond IL-6, several cytokines have been shown to be elevated in CRS and to contribute to tissue damage. TNF-α is important in nearly all acute inflammatory reactions, acting as an amplifier of inflammation. TNF-α blockade has been used to treat more than ten different autoimmune inflammatory diseases, suggesting that this might be a potential therapeutic approach to reduce organ damage in patients with ). IL-1 is also a highly active pro-inflammatory cytokine, and monotherapy blocking

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Background Early reports indicate that AKI is common among patients with coronavirus disease 2019 (COVID-19) and associated with worse outcomes. However, AKI among hospitalized patients with COVID-19 in the United States is not well described. Methods This retrospective, observational study involved a review of data from electronic health records of patients aged $18 years with laboratory-confirmed COVID-19 admitted to the Mount Sinai Health System from February 27 to May 30, 2020. We describe the frequency of AKI and dialysis requirement, AKI recovery, and adjusted odds ratios (aORs) with mortality. Results Of 3993 hospitalized patients with COVID-19, AKI occurred in 1835 (46%) patients; 347 (19%) of the patients with AKI required dialysis. The proportions with stages 1, 2, or 3 AKI were 39%, 19%, and 42%, respectively. A total of 976 (24%) patients were admitted to intensive care, and 745 (76%) experienced AKI. Of the 435 patients with AKI and urine studies, 84% had proteinuria, 81% had hematuria, and 60% had leukocyturia. Independent predictors of severe AKI were CKD, men, and higher serum potassium at admission. In-hospital mortality was 50% among patients with AKI versus 8% among those without AKI (aOR, 9.2; 95% confidence interval, 7.5 to 11.3). Of survivors with AKI who were discharged, 35% had not recovered to baseline kidney function by the time of discharge. An additional 28 of 77 (36%) patients who had not recovered kidney function at discharge did so on posthospital follow-up. Conclusions AKI is common among patients hospitalized with COVID-19 and is associated with high mortality. Of all patients with AKI, only 30% survived with recovery of kidney function by the time of discharge.

Initially, children were thought to be spared from disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). However, a month into the epidemic, a novel multisystem inflammatory syndrome in children (MIS-C) emerged. Herein, we report on the immune profiles of nine MIS-C cases. All MIS-C patients had evidence of prior SARS-CoV-2 exposure, mounting an antibody response with intact neutralization capability. Cytokine profiling identified elevated signatures of inflammation (IL-18 and IL-6), lymphocytic and myeloid chemotaxis and activation (CCL3, CCL4, and CDCP1) and mucosal immune dysregulation (IL-17A, CCL20, CCL28). Immunophenotyping of peripheral blood revealed reductions of non-classical monocytes, and subsets of NK- and T- lymphocytes, suggesting extravasation to affected tissues. Finally, we profiled the auto-antigen reactivity of MIS-C plasma, which revealed both known disease-associated autoantibodies (anti-La) and novel candidates that recognize endothelial, gastrointestinal and immune-cell antigens. All patients were treated with anti-IL6R antibody and/or IVIG, which led to rapid disease resolution.