Diagnosis: Pemphigoid gestationis

  • Autoimmune blistering disease
  • Incidence: 1 in 10,000-50,000 pregnancies
  • Starts in 2nd or 3rd trimester (mean onset = 21 weeks)
  • Presents as pruritic papules and vesicles/bullae
  • Involves the umbilicus in fifty percent of cases

Histopathology often helps with the diagnosis. Findings include a subepidermal blister with eosinophils.Z

Immunofluorescence provides a definitive diagnosis with findings of a linear band of C3 +/- IgG at the basement membrane zone.Z

Treatment

1- Topical steroids can be helpful in mild disease.

2- With widespread disease, patients will often benefit from oral steroids, which are safe to use in pregnancy (category B drug).

Complications

  1. Preterm delivery
  2. Small-for-gestational age infants
  3. Blisters (10% risk) in the neonate secondary to maternal transfer of antibodies.

Prognosis

1- There is often a flare at the time of delivery (75% of cases). 2- Pemphigoid gestationis can start postpartum (20% of cases). 3- Recurrence with menses or OCP use has been reported but is rare.

Case One

Safa

  • Safa is a 34-year-old woman who presents with a one-month history of a skin eruption.
  • She is 31 weeks; 3rd trimester pregnant with her first child.
  • She says that she first noticed the eruption after she swam in a lake.
  • The rash started on her abdomen and rapidly spread to her arms and legs.
  • The eruption is very pruritic and sometimes forms blisters.
  • She tried applying calamine lotion, which provided temporary relief. The lesions, however, continue to progress.
  • She is otherwise healthy and is on prenatal multivitamins.

Skin Exam