CD40LG and COVID-19: The multivariable logistic regression analysis (Table 4) identified the number of doses of COVID-19 vaccine, number of episodes of COVID-19, eGFR and SARS-CoV-2 IgM measured during quarantine; and WBC count SARS-CoV-2 IgG, and SARS-CoV-2 IgM at the time of diagnosis, as independent risk factors for re-positivity.