Successful treatment of COVID-19-associated collapsing glomerulopathy: 22 months of follow-up

Abstract

The term COVAN (COVID-19-associated nephropathy) has been used to describe collapsing focal segmental glomerulosclerosis (FSGS) in individuals who have been infected with the SARS-CoV-2. This helps differentiate it from the majority of cases of acute kidney injury in COVID-19 patients, which are typically caused by acute tubular injury. The exact pathophysiology is unclear but is proposed to involve pro-inflammatory cytokines such as type 1 interferons, which are thought to increase expression of the APOL1 gene in glomerular epithelial cells. This triggers a cascade of inflammatory events that cause damage to the epithelia and underlying podocytes. The treatment of COVAN is centered on general supportive measures including dietary sodium restriction, optimization of hyperlipidemia and hypertension, RAAS blockade, and diuresis for edema. There is limited data to support the use of glucocorticoids in COVAN; however, the mechanism of podocytopathy is similar to that in HIVAN (HIV-associated nephropathy), with high disease burden in those with APOL1 gene mutation. Based on previous experience, treatment of HIVAN with glucocorticoids is beneficial and safe in selected patients. Here we present a case of COVAN which was successfully treated with glucocorticoids, and at 22-month follow-up patient remained in full remission (proteinuria < 1,000 mg/g) with stable kidney function.