Relapsing COVID-19 infection as a manifestation of Good syndrome: a case report and literature review

•Good syndrome (GS) is a rare acquired immunodeficiency.•Relapsing bacterial and viral infections are common in GS.•Relapsing COVID-19 infection has not been previously reported in GS.•We report a case of GS manifesting as relapsing COVID-19 infection. Good syndrome (GS) is a rare acquired immunodeficiency disease characterized by the presence of thymoma with combined B and T cell immunodeficiency in adults. Recurrent bacterial infections, particularly sinopulmonary infections caused by encapsulated bacteria, remain the most common infective presentation of GS; however, relapsing viral infections have also been reported, likely due to impaired T cell-mediated immunity. Relapsing COVID-19 infection, however, has not been previously reported as a manifestation of GS. We present two cases of relapsing COVID-19 infection in patients with GS; in one case, relapsing COVID-19 was the first manifestation of newly diagnosed GS.