Autoantibodies in moderate and critical cases of COVID‐19

Antinuclear antibodies (ANAs) detected by indirect immunofluorescence (IIF) method in acute COVID-19 infection; future roadmap for laboratory diagnosis

“…In the observation with the context of severe COVID-19, numerous antibody secreting cells are produced as a result of upregulation of extrafollicular B cells, including clonotypes that are autoreactive ( Woodruff et al, 2020 ). Considering these data in cellular structuring, ANA was detected in 18% of COVID-19 patients in our study, but this was lower than the data in the literature (21.3%–64%) ( Pascolini et al, 2021 ; Gazzaruso et al, 2020 ; Lerma et al, 2020 ; Sacchi et al, 2020 ; Chang et al, 2021b ; Chang et al, 2021a ; Trahtemberg et al, 2021 ). The relationship between disease severity or the time of sampling and antibody titers were not significant, but the majority of ANAs were strongly positive at a titer of 3+.…”

“…The relationship between disease severity or the time of sampling and antibody titers were not significant, but the majority of ANAs were strongly positive at a titer of 3+. Although attempts were made to correlate ANA titer with clinical severity in the selected group of patients, both weak and strong positive titers were reported ( Pascolini et al, 2021 ; Chang et al, 2021b ). None of the patients in our study group had a history of a SARD or oncologic disease in which biological agents were used.…”

“…Although various ANA patterns have been detected in the initiation of COVID-19, the presence of patterns directed mainly against nuclear antigens has been reported ( Lerma et al, 2020 ; Chang et al, 2021b ; Chang et al, 2021a ). In agreement with the literature, mainly nucleolar patterns were detected in our study.…”

“…In COVID-19 patients, detectable anti-CCP levels with ANA positivity have been reported in limited series of patients and in wide ranges (2.1%–20%) ( Chang et al, 2021b ; Vlachoyiannopoulos et al, 2020 ; Roongta et al, 2021 ). It has been reported that a patient who developed arthritis after COVID-19 infection and had anti-CCP positivity became seropositive for rheumatoid factor ( Roongta et al, 2021 ).…”

“…Nuclear antigens are usually the target of autoantibodies and anti-nuclear antibodies (ANA) can be detected in many autoimmune diseases such as systemic lupus erythematosus (SLE), but also in many viral infections ( Sener et al, 2014 ). Although there are several studies in the literature, autoantibodies are commonly seen in COVID-19 patients (21.3%–64%), but larger studies are needed to investigate their association with disease prognosis ( Pascolini et al, 2021 ; Gazzaruso et al, 2020 ; Lerma et al, 2020 ; Sacchi et al, 2020 ; Chang et al, 2021b ; Chang et al, 2021a ; Trahtemberg et al, 2021 ). However, because ANA is also positive in the healthy population (with a weak titer and prevalence ranging from 8% to 15%) and in other clinical conditions, positive results must be interpreted with clinical data ( Kaklıkkaya et al, 2020 ; Yurttutan Uyar et al, 2017 ; Damoiseaux et al, 2016 ).…”