The desmoglein (Dsg) enzyme-linked immunosorbent assay (ELISA) is a sensitive and specific test for pemphigus vulgaris (PV),^1,2 which, during pregnancy, is exceedingly rare.³ To our knowledge, the clinical patterns of PV activity monitored using Dsg ELISA during pregnancy and after delivery have not been reported. Transplacental anti-Dsg antibody transfer has not previously been confirmed using Dsg ELISA.

A 24-year-old pregnant Japanese woman who was in the 18th week of gestation developed a mucosal dominant form of PV. Direct immunofluorescence tests revealed intercellular IgG and C3 deposits in the epidermis. Indirect immunofluorescence demonstrated that the autoantibody titer was 1:40. The Dsg1- and Dsg3-ELISA index of her serum was scored at 0.4 (cutoff, 14.0) and 60.3 (cutoff, 7.0), respectively (Dsg ELISA Kit; Medical & Biological Laboratories, Nagoya, Japan). The ELISA indexes of Dsg1 and Dsg3 were scored approximately every other week using the appropriate serum dilutions recommended by Cheng et al.⁴ Oral prednisolone therapy (20 mg after breakfast and 10 mg after lunch [30 mg/d]) was effective. The Dsg3-ELISA index decreased to 38.5 in the 34th week of gestation after almost all the PV lesions had become epithelialized. The prednisolone therapy was tapered to 20 mg/d by the time of expected delivery (Figure 1). In the 37th week of gestation, she was delivered of a healthy male neonate, 2700 g, who was free from cutaneous and mucosal lesions. The PV of the mother was clinically completely inactive at the time of delivery. At the time of delivery, the Dsg3-ELISA index was 41.4 for the maternal serum and 24.9 for the cord serum, which corresponds to the serum of the neonate. Four weeks after the birth, the Dsg3-ELISA index of the serum of the baby decreased to 0.2. The baby remained free of skin and mucosal lesions for the following year. The Dsg1-ELISA index of the neonate remained below the cutoff level (Table 1).