COVID-19-Related Glomerulopathy: A Report of 2 Cases of Collapsing Focal Segmental Glomerulosclerosis.

Coronavirus disease 19 (COVID-19), an infectious disease caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has been associated with acute kidney injury, presumably due to acute tubular injury. However, this does not explain proteinuria, sometimes severe, and hematuria often observed. We present 2 African American patients with glomerulopathy demonstrated by kidney biopsy in the setting of acute kidney injury and COVID-19 infection. Kidney biopsy specimens showed a collapsing variant of focal segmental glomerulosclerosis in addition to acute tubular injury. Both patients were homozygous for apolipoprotein L1 ( APOL1 ). COVID-19 infection likely caused the interferon surge as a second hit causing podocyte injury leading to collapsing focal segmental glomerulosclerosis. APOL1 testing should be strongly considered in African American patients with nephrotic-range proteinuria. More data from future kidney biopsies will further elucidate the pathology of kidney injury and glomerular involvement from COVID-19 infections.