De Novo ANCA (-) Pauci-Immune Crescentic Glomerulonephritis After Injection of COVID-19 mRNA Vaccine

ABSTRACT

Introduction: To prevent the spread of the COVID-19 pandemic, vaccinations have been authorized for emergency use and implemented worldwide. As with the others, COVID-19 vaccines are known to cause mild and transient side effects such as fever, myalgia, and fatigue, but severe and consistent adverse events have rarely been reported. We present a case of de novo glomerulonephritis after injection of COVID-19 mRNA vaccine, BNT162b2 (BioNTech, Pfizer, NY, USA). Case Description A 48-year-old man with no past medical history was referred for suddenly and persistently worsening renal insufficiency for only a month and a half after the second dose injection of the vaccine. He presented with arthralgia and skin rash a week after the vaccination. Abdominal pain and diarrhea started two weeks later, and he was admitted to the hospital for enteritis treatment. Upon colonoscopy, multiple ulceration and petechiae suggestive of vasculitis were observed in the terminal ileum. While taking prednisolone for a few weeks the gastrointestinal symptoms improved, but the renal function continues to deteriorate. A kidney biopsy was performed for the rapid decline in renal function accompanying nephrotic-range proteinuria (urine protein to creatinine ratio 3389mg/gCr), and anti-neutrophil cytoplasmic autoantibody (ANCA)-negative pauci-immune crescentic glomerulonephritis was diagnosed. He started treatment with high-dose steroid pulse therapy and oral cyclophosphamide, and then gradually took steroid tapering, showing improvement in proteinuria and renal function over several weeks. Discussion(s) To date, several cases of glomerulonephritis suspected to be related to the COVID-19 vaccine have been reported. This is the first case report of ANCAnegative pauci-immune crescentic glomerulonephritis with extrarenal involvement after COVID-19 mRNA vaccine injection. It is difficult to find definite evidence to suspect or prove the causal relationship, except when there is a temporal association after vaccination or when the disease manifestations are unusual compared to well-known pathologic findings. Further in-depth studies are needed for de novo glomerulonephritis that occurs after vaccination and COVID-19 infection.