Quarantining dialysis patients infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a logistical challenge. Appropriately identifying noninfectiousness in patients is essential to safely lift quarantine measures. Serologic tests are used to establish previous infection with SARS-CoV-2, but the extent to which antibody positivity translates to actual immunity is currently unknown.1 Hemodialysis patients are known to have impaired humoral immune responses to vaccination and infection, and it is uncertain whether hemodialysis patients mount an effective antibody response against SARS-CoV-2.