New-onset ANCA-associated vasculitis presenting with neuropathy after COVID-19 infection: A case report and literature review.

Coronavirus Disease 2019 (COVID-19) is a viral infection caused by SARS-CoV-2, which can trigger autoimmune diseases such as antineutrophilic cytoplasmic antibody (ANCA) associated vasculitis (AAV) that affect small and medium-sized blood vessels in multiple organs. This study discusses a case with neuropathy and positive ANCA after COVID-19 infection and reviews the literature on AAV following COVID-19 infection. A 59-year-old man is presented that was referred to Shariati Hospital for evaluation of neurologic problems after a COVID-19 infection. Initially, he had flu-like symptoms. A few days later, he developed right distal upper and lower limb paresthesia. His electromyography (EMG) and nerve conduction velocity (NCV) results were consistent with polyneuropathy. Lumbar puncture (LP) was normal except for positive COVID-19 polymerase chain reaction (PCR). The patient's paresthesia worsened. Laboratory data showed leukocytosis, anemia, thrombocytosis, high erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP). Perinuclear anti-neutrophil cytoplasmic antibody (MPO-ANCA) was positive. According to the results, vasculitis was the main differential diagnosis. The sural nerve biopsy was performed, and the result was consistent with small to medium-sized vessel vasculitis. The patient was diagnosed with COVID-induced AAV. He was prescribed methylprednisolone and cyclophosphamide and was discharged with prednisolone and cotrimoxazole. In this study, a unique case of AAV induced by COVID-19 infection confirmed by nerve biopsy is presented. A review of the literature found 48 cases of new-onset AAV in adults and pediatrics after COVID-19 infection. Further research is needed to completely understand the relationship between COVID-19.