DSG3 and acquired polycythemia vera: During a mean 7.8 ± 5.8 (2‒21) years follow-up period after the transition from PV to PF, only one female patient had experienced a re-transition to PV characterized by a relapse of disease involving mucosal surfaces with positive anti-Dsg3 antibody levels following a 5-year period of remission period without treatment.