GPP Awareness Day: Recognizing Severity Across Care Settings

“I think one of the keys here is to make sure that all of these colleagues of ours in the House of Medicine have your cell phone number, so that when they're really unsure of something…when they call you, you'll be there to pick up the phone call and help this patient,” said Aaron Farberg, MD, in a recent interview.

Farberg, a double-board-certified dermatologist and Mohs surgeon and the chief medical officer at Bare Dermatology in Dallas, Texas, discussed the diagnostic complexity of generalized pustular psoriasis in recognition of Generalized Pustular Psoriasis (GPP) Awareness Day, August 13. Farberg, who also leads the dermatology residency program at Lake Granbury Medical Center, outlined how the condition's presentation varies by clinical setting and often leads clinicians toward alternative diagnoses before dermatology becomes involved. He also addressed the chronic phase of GPP and the value of accessible dermatology consultation.

Classic Presentation and Common Misdiagnoses

In its classic presentation, GPP produces eruptive pustules coalescing into pus on erythematous skin, accompanied by systemic inflammatory signs such as fever, malaise, and rigors, along with laboratory abnormalities including leukocytosis, neutrophilia, and elevated CRP.¹ Farberg said this textbook picture is not always present, and the differential shifts depending on where a patient is evaluated.

"You have lakes of pus from these pustules that coalesce. That's literally the textbook answer and what you'd hope to see in a picture," Farberg said.

In the emergency department, GPP can be mistaken for septic shock or severe cellulitis. In urgent care, it may be diagnosed as a severe drug eruption, severe eczema, or impetigo. Once a patient is hospitalized, clinicians may instead suspect acute generalized exanthematous pustulosis (AGEP), given the range of treatments administered there.²

Recognizing GPP in Its Chronic Phase

Beyond the acute presentation, Farberg described a chronic, smoldering phase of GPP in which active pustules may not be present. He said skin pain, particularly pain elicited by palpation, served as a key diagnostic clue in one of his patients.

"One of the keys for one of the patients that I had diagnosed was particularly skin pain," Farberg said. "They had a history of pustules. They didn't have it right then and there at that moment in the office, but they just described this significant increase in their overall pain that they describe when you press on the skin."

Improving GPP Diagnosis Through Dermatology Access

Farberg said GPP Awareness Day serves to raise awareness of the condition across the broader House of Medicine, not only among dermatologists. He compared diagnostic reasoning to the classic teaching of listening for hoofbeats and thinking of horses rather than zebras.

"When you hear the beat of hoofbeats, you have to think of a horse, think of a common animal that's going to make that noise, but what makes us very good clinicians is you also have to think about the zebras," Farberg said.

Farberg recommended dermatologists make themselves directly accessible to colleagues across specialties, including sharing a personal phone number, so uncertain cases receive timely input.

References

1. Armstrong AW, Elston CA, Elewski BE, Ferris LK, Gottlieb AB, Lebwohl MG; Medical Board of the National Psoriasis Foundation. Generalized pustular psoriasis: A consensus statement from the National Psoriasis Foundation. J Am Acad Dermatol. 2024;90(4):727-730. doi:10.1016/j.jaad.2023.09.080
2. Yeung J, Prajapati VH, Mutter E, Gooderham M. Just the facts: diagnosis and management of generalized pustular psoriasis. CJEM. 2025;27(7):514-517. doi:10.1007/s43678-025-00883-9