Article
Author: Yukishima, Toshitaka  ; Yamashita, Keita  ; Ogawa, Noriyoshi  ; Taki, Takeru  ; Azuma, Chika  ; Maekawa, Masato  ; Furukawa, Shogo  ; Nagura, Osanori  ; Furuhashi, Kazuki  ; Shimoyama, Kumiko  ; Fukami, Soma  ; Katahashi, Kazuto  ; Yamazaki, Kenji 
A 67-year-old woman with anti-neutrophil cytoplasmic autoantibody (ANCA)-associated vasculitis was not vaccinated against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and was on multiple immunosuppressive drugs. She was hospitalized because of interstitial shadowing in the lungs and diagnosed with persistent coronavirus disease 2019 (COVID-19). Despite treatment with a recombinant monoclonal antibody and antivirals, her symptoms persisted and she lacked a specific antibody response. She tested negative for SARS-CoV-2 antigen after the second antiviral treatment, and a subsequent chest radiograph showed improvement. However, the antibody levels did not change. This case highlights the importance of careful monitoring of the SARS-CoV-2 antigen and antibody levels during COVID-19 treatment in patients with immunosuppression.