A 56-year-old African American man with past medical history of diabetes mellitus presented with increased shortness of breath and fever for 1 week. On admission, he tested positive for COVID-19. Pulse oxygen was 89% on room air. Physical examination was notable for rales at his lung basis, diffuse anasarca, mild abdominal distension, and 3+ pitting edema in his ankles. Chest X-rays showed diffuse pulmonary edema with a small amount of pleural effusion bilaterally. Ultrasound of the abdomen revealed small amount of ascites and moderate abdominal wall edema. He was admitted to the ICU step down unit for close monitoring and further treatment. Laboratory studies are listed below:
- Serum creatinine 2.5 mg/dL (baseline 1.0 mg/dL)
- Blood urea nitrogen (BUN) 63 mg/dL
- Serum sodium 136 mmol/L, potassium 4.5 mg/dL, chloride 106 mmol/L, CO2 18 mmol/L, calcium 8.4 mg/dL
- Serum albumin 2.3 mg/dL
- White blood cell count 16 x 109 cells/L
- Urine protein-to-creatinine ratio (PCR) 6.5 g/g (baseline urine PCR 0.3 g/g)
- 24-hour urine collection revealed 8.9 g protein
- Urine microscopy showed a few muddy brown casts and rare non-dysmorphic red blood cells.
A kidney biopsy was performed as soon as the patient’s respiratory status stabilized. It showed collapsing glomerulopathy with hypertrophy and hyperplasia of visceral epithelial cells. Protein droplets were observed in the glomeruli and renal tubules along with focal acute tubular injury. Electron microscopy showed extensive foot process effacement.