Are clinical phenotype and autoantibody profile always concordant in pemphigus? A study in a cohort of pemphigus patients

Background: The clinical phenotype of different forms of pemphigus is reportedly defined by the anti-desmoglein (Dsg) autoantibody profile. In routine practice, however, this is not always the case. Objectives: To verify the relationship between the anti-Dsg1 and -3 autoantibody profiles and titers on the one hand and the clinical phenotype and disease activity on the other. Materials and Methods: we followed-up clinically and serologically 20 pemphigus patients, including 3 mucosal pemphigus (mPV), 9 mucocutaneous pemphigus (mcPV), and 8 cutaneous pemphigus (PF). Results: We found that the cutaneous and/or mucosal involvement and the autoantibody profile were only concordant in mPV patients. On the contrary, in other clinical forms this correlation was often absent. Conclusions: 1) The discrepancy between autoantibody profile and the clinical phenotype, at least in PF patients, appears to be due to non-pathogenic anti-Dsg3 antibodies; 2) in a proportion of patients the relationship between the Dsg1 and Dsg3 ELISA titers and the disease severity was absent; 3) in some patients, the anti-Dsg1 and -3 autoantibodies were lacking at diagnosis, suggesting a role of other antigens in the pathogenesis of the disease and, lastly, 4) the pure cutaneous and mucosal forms tend to respond more efficiently to the therapy than the mucocutaneous forms and have a persistent response.