“In psoriasis, there are microscopic little collections of pus cells,” says Steven Feldman, MD, PhD, a dermatologist who specializes in psoriasis at Atrium Health Wake Forest Baptist in Winston-Salem, North Carolina. “But in generalized pustular psoriasis, which is a very abrupt and severe flare, people get the psoriasis all over their body, and those little microscopic pus cells get so large that they are visible with the naked eye.”
In severe cases, GPP can become life-threatening if left untreated.
- Acute GPP
- Annular pustular psoriasis
- Localized or chronic acral GPP
- Pustular psoriasis of pregnancy
- Infantile and juvenile pustular psoriasis
- Mixed GPP
Acute GPP
Acute GPP is also called GPP of von Zumbusch, named after the dermatologist who first described it in 1910. It starts rapidly within seven days of a flare. It is the most severe and most common form of the disease, affecting about 90 percent of people with GPP.
Annular Pustular Psoriasis
Annular pustular psoriasis is a milder category of GPP. It is limited and recurrent, typically flaring between 7 to 90 days after the onset of GPP.
Localized or Chronic Acral GPP
Chronic acral GPP flares over three months. Lesions appear on the feet, hands, arms, legs, and other acral extremities. Over time, it can spread elsewhere on the body.
Pustular Psoriasis of Pregnancy
Pustular psoriasis during pregnancy is called impetigo herpetiformis. It typically starts in the final trimester and is caused by and made worse by the pregnancy. It can lead to placental insufficiency, stillbirth, fetal abnormalities, and early death.
Infantile and Juvenile Pustular Psoriasis
GPP in children typically starts between the ages of 3 and 16. It is estimated to comprise 0.3 to 7 percent of child psoriasis cases. Although it can be life-threatening, GPP in children resolves on its own more often than in adult cases and is more likely to enter remission, as well.
Mixed GPP
It is also possible to have mixed GPP, in which you present symptoms of more than one subtype.