Impetigo herpetiformis is a rare pustular disorder that affects pregnant women. It is also otherwise termed as “pustular psoriasis of pregnancy”, owing to the fact that the pustules are sterile and are not associated with a viral etiology. The classic lesions are erythematous patches or plaques with margins studded with subcorneal
pustules spreading centrifugally. A cardinal feature of this disorder is the rapid resolution of lesions after delivery.
This is a case report of a 33-year-old female, gravida 3, para 2 (2-0-0-2) at 36 weeks age of gestation who presented with one week history of multiple well defined irregularly shaped erythematous annular patches and plaques with marginal pustules on the trunk and extremities. The lesions began on the trunk spreading centrifugally, sparing the face, palms, soles and mucus membrane. Biopsy showed scale crust in the stratum corneum, the epidermis showed acanthosis, spongiosis and neutrophilic microabscesses with focal vacuolar alteration and small sub-epidermal nests on the basal cell layer. The dermis revealed dilated blood vessels and mild superficial perivascular lymphocytic infiltrates. Patient was given Prednisone and Cetirizine with noted resolution of lesions.
Recurrences of impetigo herpetiformis in subsequent pregnancies are common with earlier onset in gestation and are characteristically more severe. The complications are placental insufficiency, stillbirth or neonatal death. Early detection is of utmost importance. Management must be multidisciplinary involving a dermatologist, obstetrician, and pediatrician.