Coronavirus disease 2019 (COVID-19) is an infectious disease that is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) [1]. COVID-19 is now recognized as a multisystem disease with a broad spectrum of manifestations [[2], [3], [4]]. The pathophysiology of COVID-19 remained unclear; however, much evidence supports the hypothesis that SARS-CoV2 could stimulate autoimmunity in predisposed patients. Histopathological signs of autoimmune reactions have been demonstrated in many organ systems of deceased patients from COVID-19. CD8 T lymphocyte-infiltrated lungs, adrenals, liver, intestine, and other organs confirm an autoimmune process [5]. SARS-CoV-2 can break immunological tolerance by molecular mimicry, standard activation, and epitope spreading and therefore, induce autoimmune diseases (AIDs) [6]. Moreover, the incidence of many AIDs has increased since the beginning of the COVID-19 pandemic [[7], [8], [9]].

Saccharomyces cerevisiae (S. cerevisiae) is a yeast that is used for bread baking and is one of the predominant yeast in our mycobiota [10]. Anti-S. cerevisiae antibodies (ASCA) are directed against the phosphopeptidomannan, a part of the cell wall of S. cerevisiae. ASCA is considered one of the serological markers of Crohn’s disease [[11], [12]]. Combined with perinuclear anti-neutrophil cytoplasmic antibodies, ASCA has been reported as a valuable marker to discriminate between Crohn’s disease and ulcerative colitis [13]. Additionally, ASCA has been detected in many AIDs [[14], [15], [16], [17], [18], [19]]. However, to our knowledge, only one study has determined ASCA in COVID-19 [20]. Therefore, the present study aimed to determine the frequency of ASCA in this viral disease, which could induce AIDs.