[Transition from pemphigus vulgaris to pemphigus foliaceus: a case report]

Is transition between subtypes of pemphigus possible? A series of pemphigus vulgaris patients showing the transition to pemphigus foliaceus

BACKGROUND

Pemphigus vulgaris (PV) and pemphigus foliaceus (PF) are subtypes of pemphigus with distinct clinical and laboratory features. The transition between these two subtypes has rarely been reported previously.

METHODS

The data of PV patients who exhibited clinical and immunoserological transition to PF during the follow-up period were retrospectively evaluated regarding their demographical, clinical, and laboratory characteristics.

RESULTS

Among 453 patients diagnosed with PV, 13 (2.9%) patients exhibited clinical and immunoserological transition from PV to PF. The mean age of PV patients at the time of diagnosis was 39.8 ± 14.7 (19‒62) years and 7 (53.8%) of them were female. These patients showed clinical and immunoserological transition from PV to PF after a period ranging from 4 months to 13 years (mean 36.2 ± 41 months). In addition to typical clinical features of PF, all patients had positive anti-desmoglein-1 and negative anti-desmoglein-3 antibody levels after the clinical transition had occurred without any mucosal involvement. During a mean 7.8 ± 5.8 (2‒21) years of 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-desmoglein-3 antibody levels following a 5-year period of remission period without treatment.

STUDY LIMITATIONS

Single-center study with a retrospective study design.

CONCLUSION

Our series is the largest group of patients reported to show the transition from PV to PF to date with a long follow-up period. The reason behind the disappearance of anti-desmoglein-3 antibodies and the pathogenesis of this phenomenon is not yet elucidated.

Humoral Epitope Spreading in Autoimmune Bullous Diseases

Autoimmune blistering diseases are characterized by autoantibodies against structural adhesion proteins of the skin and mucous membranes. Extensive characterization of their autoantibody targets has improved understanding of pathogenesis and laid the basis for the study of antigens/epitopes diversification, a process termed epitope spreading (ES). In this review, we have reported and discussed ES phenomena in autoimmune bullous diseases and underlined their functional role in disease pathogenesis. A functional ES has been proposed: (1) in bullous pemphigoid patients and correlates with the initial phase of the disease, (2) in pemphigus vulgaris patients with mucosal involvement during the clinical transition to a mucocutaneous form, (3) in endemic pemphigus foliaceus, underlining its role in disease pathogenesis, and (4) in numerous cases of disease transition associated with an intermolecular diversification of immune response. All these findings could give useful information to better understand autoimmune disease pathogenesis and to design antigen/epitope specific therapeutic approaches.