Background: Desmoglein (Dsg) enzyme-linked immunosorbent assay (ELISA) is a highly sensitive and specific method to detect anti-Dsg3 and anti-Dsg1 IgG autoantibodies in pemphigus vulgaris (PV) and pemphigus foliaceus (PF), respectively. Whereas ELISA index values fluctuate in parallel with disease activity, ELISA positivity during clinical remission has been observed.
Objective: To determine the prevalence of positive Dsg ELISA index values during clinical remission. To ascertain how positive Dsg ELISA scores during remission compare with those during active disease.
Methods: Dsg ELISA was performed on serum samples of PV and PF patients taken during remission (lesion-free >or= 3 months on <or= 15 mg or <or= 5 mg/day prednisolone) and active disease. We used a modified ELISA protocol with optimal serum dilutions in sera with very high initial index values, as we previously described.
Results: When remission was defined as no eruption >or= 3 months with <or= 15 mg/day prednisolone, 20 of 43 PV patients (46.5%) and 4 of 12 PF patients (33.3%) showed Dsg3 and Dsg1 ELISA positivity, respectively. With <or= 5 mg/day, 6 of 17 PV (35.3%) and 1 of 6 PF patients (16.7%) showed Dsg3 and Dsg1 ELISA positivity, respectively. The index value of each ELISA-positive remission serum was consistently lower than that of its corresponding active disease serum. We observed consistent correlation between ELISA index values and indirect immunofluorescence titres.
Conclusions: Circulating anti-Dsg IgG autoantibodies are found in a considerable percentage of pemphigus patients in remission, who have high levels of antibody production during active stages.