Pustular Psoriasis: From Pathophysiology to Treatment

Pustular psoriasis (PP) is a clinicopathological entity encompassing different variants, i.e., acute generalized PP (GPP), PP of pregnancy (impetigo herpetiformis), annular (and circinate) PP, infantile/juvenile PP, palmoplantar PP/palmoplantar pustulosis, and acrodermatitis continua of Hallopeau (ACH), which have in common an eruption of superficial sterile pustules on an erythematous base. Unlike psoriasis vulgaris, in which a key role is played by the adaptive immune system and interleukin (IL)-17/IL-23 axis, PP seems to be characterized by an intense inflammatory response resulting from innate immunity hyperactivation, with prominent involvement of the IL-36 axis. Some nosological aspects of PP are still controversial and debated. Moreover, owing to the rarity and heterogeneity of PP forms, data on prognosis and therapeutic management are limited. Recent progresses in the identification of genetic mutations and immunological mechanisms have promoted a better understanding of PP pathogenesis and might have important consequences on diagnostic refinement and treatment. In this narrative review, current findings in the pathogenesis, classification, clinical features, and therapeutic management of PP are briefly discussed.

Impetigo herpetiformis: an unknown dermatosis of pregnancy

<p>Impetigo herpetiformis or pustular psoriasis of pregnancy is a rare dermatosis of pregnancy that typically starts in the second half of pregnancy and resolves postpartum. It can be life threatening for both mother and fetus and often causes therapeutic problem. We report a case of 37-year-old pregnant woman with history of generalized pustular lesions in the two previous pregnancies, presenting an impetigo herpetiformis during her third pregnancy, resolved one day after the delivery.</p>

A case of impetigo herpetiformis in which termination of pregnancy was required

Impetigo herpetiformis is a rare variant of generalized pustular psoriasis that occurs during pregnancy or is triggered by pregnancy, often in association with hypocalcemia. This condition is associated with increased maternal and fetal morbidity and mortality. We report a 29-year-old pregnant woman who presented to hospital at the gestational age of 20 weeks with widespread erythema covered with pustules that coalesced to form lakes of pus. She did not respond to corticosteroids, immunosuppressants, or phototherapy. Finally, intra-amniotic injection of ethacridine lactate was administered to terminate the pregnancy, and the patient showed complete recovery in 3 months. Insight from this case report may facilitate optimal management of this relatively rare entity.