A multi-center retrospective cohort study defines the spectrum of kidney pathology in Coronavirus 2019 Disease (COVID-19)

May, Rebecca M.; Cassol, Clarissa; Hannoudi, Andrew; Larsen, Christopher P.; Lerma, Edgar; Haun, Randy S.; Braga, Juarez R.; Hassen, Samar I.; Wilson, Jon; VanBeek, Christine; Vankalakunti, Mahesha; Barnum, Lilli; Walker, Patrick D.; Bourne, T. David; Messias, Nidia C.; Ambruzs, Josephine M.; Boils, Christie L.; Sharma, Shree S.; Cossey, L. Nicholas; Baxi, Pravir V.; Palmer, Matthew; Zuckerman, Jonathan; Walavalkar, Vighnesh; Urisman, Anatoly; Gallan, Alexander; Al-Rabadi, Laith F.; Rodby, Roger; Luyckx, Valerie; Espino, Gustavo; Santhana-Krishnan, Srivilliputtur; Alper, Brent; Lam, Son G.; Hannoudi, Ghadeer N.; Matthew, Dwight; Belz, Mark; Singer, Gary; Kunaparaju, Srikanth; Price, Deborah; Chawla, Saurabh; Rondla, Chetana; Abdalla, Mazen A.; Britton, Marcus L.; Paul, Subir; Ranjit, Uday; Bichu, Prasad; Williamson, Sean R.; Sharma, Yuvraj; Gaspert, Ariana; Grosse, Philipp; Meyer, Ian; Vasudev, Brahm; El Kassem, Mohamad; Velez, Juan Carlos Q.; Caza, Tiffany N.

Kidney failure is common in patients with Coronavirus Disease-19 (COVID-19) resulting in increased morbidity and mortality. In an international collaboration, 284 kidney biopsies were evaluated to improve understanding of kidney disease in COVID-19. Diagnoses were compared to five years of 63,575 native biopsies prior to the pandemic and 13,955 allograft biopsies to identify diseases increased in patients with COVID-19. Genotyping for APOL1 G1 and G2 alleles was performed in 107 African American and Hispanic patients. Immunohistochemistry for SARS-CoV-2 was utilized to assess direct viral infection in 273 cases along with clinical information at the time of biopsy. The leading indication for native biopsy was acute kidney injury (45.4%), followed by proteinuria with or without concurrent acute kidney injury (42.6%). There were more African American patients (44.6%) than patients of other ethnicities. The most common diagnosis in native biopsies was collapsing glomerulopathy (25.8%) which associated with high-risk APOL1 genotypes in 91.7% of cases. Compared to the five-year biopsy database, the frequency of myoglobin cast nephropathy and proliferative glomerulonephritis with monoclonal IgG deposits was also increased in patients with COVID-19 (3.3% and 1.7%, respectively), while there was a reduced frequency of chronic conditions (including diabetes mellitus, IgA nephropathy, and arterionephrosclerosis) as the primary diagnosis. In transplants, the leading indication was acute kidney injury (86.4%), for which rejection was the predominant diagnosis (61.4%). Direct SARS-CoV-2 viral infection was not identified. Thus, our multi-center large case series identified kidney diseases that disproportionately affect patients with COVID-19, demonstrated a high frequency of APOL1 high-risk genotypes within this group, with no evidence of direct viral infection within the kidney.