Neonatal pemphigus foliaceus.

BACKGROUND: Pemphigus refers to a group of autoimmune blistering diseases of the skin. Of the two major types of pemphigus, pemphigus vulgaris and pemphigus foliaceus, only pemphigus vulgaris has been known to affect newborn infants via passive transfer of maternal IgG antibodies across the placenta. Although pemphigus foliaceus antibodies have also been shown to cross the placenta, never before has a newborn been clinically affected. We report the first of neonatal pemphigus foliaceus confirmed by both clinical presentation and immunofluorescence studies.

OBSERVATIONS: The distinguishing factors in this case were high antibody titers by indirect immunofluorescence present in both the mother and her fetus (1:640 and 1:80, respectively).

CONCLUSIONS: A threshold of fetal antibody titer ( > 1:40) may need to be surpassed before neonatal disease can occur in pemphigus foliaceus. The likelihood of reaching this threshold has been shown to be increased with higher maternal antibody titers. Thus, strict control of maternal pemphigus foliaceus should lower the incidence of placental antibody transfer and improve neonatal outcome.