New-onset Nephrotic Syndrome after Janssen COVID-19 Vaccination: a Case Report and Literature Review

Abstract

Various coronavirus disease 2019 (COVID-19) vaccines are being developed, which show practical preventive effects. Here, we report a 51-year-old healthy man with nephrotic syndrome secondary to minimal change disease (MCD) after Ad26.COV.2 (Janssen) vaccination. He had no comorbid disease and received Ad26.COV.2 on April 13, 2021. Seven days after vaccination, he developed edema and foamy urine. Edema rapidly aggravated with decreased urine volume. He was admitted to the hospital 28 days after vaccination, and his body weight increased by 21 kg after vaccination. His serum creatinine level was 1.54 mg/dL, and 24-h urinary protein excretion was 8.6 g/day. Kidney biopsy revealed no abnormality in the glomeruli and interstitium of the cortex and medulla under the light microscope. Electron microscopy revealed diffuse effacement of the podocyte foot processes, thus, he was diagnosed with MCD. High-dose steroid therapy was applied, and his kidney function improved three days after steroid therapy. Three weeks after steroid use, his serum creatinine decreased to 0.95 mg/dL, and spot urine protein-to-creatine decreased to 0.2 g/g. This case highlights the risk of new-onset nephrotic syndrome secondary to MCD after vectored COVID-19 vaccination. Although the pathogenesis is uncertain, clinicians need to be careful about adverse renal effects of COVID-19 vaccines.

Keywords: COVID-19; Minimal Change Disease; Nephrotic Syndrome; Vectored Vaccine.

Fig. 1. Clinical course after vaccination.

Fig. 2. Histopathological findings of kidney biopsy. (A) No tubular injury and tubular atrophy/interstitial fibrosis (periodic acid-Schiff; original magnification ×40). (B) Normal appearance glomeruli (periodic acid-Schiff; original magnification ×200). (C) Normal glomerular basement membrane without deposits (periodic acid-methenamine silver; original magnification ×400). (D) Protein reabsorption droplet accumulation in proximal tubules, which indicates heavy protein leakage across the glomerular filter and increased reabsorption of protein (periodic acid-Schiff; original magnification ×400). (E) Diffuse effacement of the podocyte foot processes and microvilli formation (electron microscopy; original magnification ×5,000).