Pemphigus erythematosus, initially described as a combination of
pemphigus with lupus erythematosus, and
pemphigus foliaceus are now frequently considered localized and generalized variants of superficial
pemphigus. Yet diagnostic criteria for
pemphigus erythematosus remain controversial. Distinct from
pemphigus foliaceus,
pemphigus erythematosus displays immune depositions at the dermal-epidermal junction, which suggests additional immunopathological mechanisms. We present three patients with clinical and histopathologic signs of superficial
pemphigus, who all exhibited an immunomorphology characteristic of
pemphigus erythematosus.
Complement depositions in a granular-linear fashion were consistently found at the dermal-epidermal junction besides in vivo bound and circulating antikeratinocyte cell-surface
autoantibodies. Histopathology showed subcorneal
acantholysis, and all sera contained antidesmoglein 1 but not antidesmoglein 3
autoantibodies detected by
enzyme-linked
immunosorbent assays (ELISA). Additional
autoantibodies against a 230-kDa
protein and against a 190-kDa
protein comigrating with
bullous pemphigoid antigen 1 (BP230) and periplakin, respectively, were present in all the patients' sera. As two sera specifically reacted with BP230 by ELISA, the presence of BP230-specific
autoantibodies could be associated with dermal-epidermal immune staining in these patients. In
pemphigus erythematosus, dermal-epidermal immune staining is generally attributed to the deposition of
immune complexes, while the presence of BP230-specific
autoantibodies has not been reported in this disease previously. Perhaps, the unique
autoantibody profile of the patients in the study permits discrimination between patients with superficial
pemphigus that display additional dermal-epidermal immune staining from those with conventional
pemphigus foliaceus on a molecular basis. Further studies will be required to substantiate the frequency of this occurrence and to unravel its pathogenic significance.