May RM, Cassol C, Hannoudi A, et al. - Researchers performed evaluation of kidney biopsies to study kidney pathology in COVID-19 patients and identified a high frequency of APOL1 high-risk genotypes in kidney diseases disproportionately affecting these patients.

• Patients with coronavirus disease-19 (COVID-19) commonly experience kidney failure.

• Acute kidney injury was the leading indication for native biopsy (45.4%), followed by proteinuria with or without concurrent acute kidney injury (42.6%).

• Collapsing glomerulopathy (25.8%) was the most common diagnosis in native biopsies, which linked with high-risk APOL1 genotypes in 91.7% of cases.

• Relative to the 5-year biopsy database, patients with COVID-19 also showed increased frequency of myoglobin cast nephropathy and proliferative glomerulonephritis with monoclonal IgG deposits, while chronic conditions (including diabetes mellitus, IgA nephropathy, and arterionephrosclerosis) appeared at a reduced frequency as the primary diagnosis.

• Acute kidney injury (86.4%) was the leading indication in transplants, for which rejection was the predominant diagnosis (61.4%).

• Direct viral infection within the kidney was not evident.