The transition of pemphigus vulgaris into pemphigus foliaceus: a reflection of changing desmoglein 1 and 3 autoantibody levels in pemphigus vulgaris.

The transition of pemphigus vulgaris (PV) into pemphigus foliaceus (PF) is rare and the immunological changes underlying this event are not well understood. We report a 44-year-old woman who presented with oral and cutaneous erosions typical of PV. Over a 9-year period, the clinical features evolved into those of PF. To examine whether quantitative changes in desmoglein (Dsg) antibodies were associated with this transition, Dsg1 and Dsg3 antibody levels were measured by enzyme-linked immunosorbent assay in 82 sequential serum samples collected over this period. At presentation, when the phenotype was PV with oral and cutaneous erosions, antibodies to both Dsg1 and Dsg3 were detected. The disappearance of oral involvement was associated with a decline in Dsg3 antibodies, which are now undetectable, while the development of more severe skin involvement was associated with rising Dsg1 antibody levels. These data strongly suggest that the change in clinical features is a reflection of qualitative and quantitative changes in antibody profile. It is not known whether the transition to PF is permanent or whether disease relapses in the future may be associated with the re-emergence of Dsg3 antibodies, oral ulceration and a PV phenotype.