GPP commonly appeared on the trunk and extremities, but was “also reported on the scalp, face, genitals, nail unit, and mucous membranes in a minority of patients,” the researchers said. Overall, 62.1% of patients had skin pain, 26.2% had joint pain, 16.8% reported tachycardia, and 9.5% reported fever. Hypertension, depression, diabetes, chronic kidney disease, and hypothyroidism were common comorbidities of GPP, the researchers noted.
Clinicians reported treating GPP with topical steroids (86.3%) and topical treatments alone (32.3%). Oral systemic treatments such as acitretin (24.2%), cyclosporine (22.1%), and methotrexate (13.7%) were also used, as well as systemic steroids (20%). Other treatments used were narrowband UVB phototherapy (5.3%) and biologic agents like adalimumab (4.2%) and infliximab (4.2%).
For 53 patients with follow-up data of at least 6 months, 19 (35.8%) had been hospitalized because of their symptoms, and 8 patients were hospitalized for further GPP-specific concerns. Patients with GPP had a median 3.2 dermatology visits per year and a maximum of 18 visits. A model that was adjusted for age and sex showed women were at a decreased risk for being admitted to the hospital or emergency department in the follow-up period (odds ratio, 0.19; 95% confidence interval, 0.04-0.83).
PPP and GPP in practice
Sylvia Hsu, MD, professor and chair of the department of dermatology at Temple University, Philadelphia, who was not involved with the research, noted that most dermatologists will see few, if any, cases of PPP and GPP in a year. At her center, she estimated that she sees about one PPP case per week, and one or two cases of GPP a year. In general, she said that her clinical experience matched what was found by the authors of both case series.
Dr. Sylvia Hsu
For patients with PPP, “I would say the average dermatologist would probably start out with a superpotent topical steroid like clobetasol or halobetasol ointment,” Dr. Hsu said.
If they are not of childbearing age, she added, she would also prescribe acitretin, which she avoids giving to patients of childbearing age because of its teratogenicity. “Acitretin has the reputation that it doesn’t work well or fast for psoriasis. It doesn’t work well or fast for plaque-type psoriasis, but it works well and fast for pustular psoriasis,” she said.
In place of acitretin, Dr. Hsu recommended cyclosporine for a patient of childbearing age as a short-term solution to resolve symptoms before transitioning them to another therapy. “A woman of childbearing age, you put on cyclosporine, you’ve got to transition to something else,” she said. “And so many times you wean them off, the pustular psoriasis comes back because the topical steroid doesn’t work that well.”
One possible option is the interluekin-23 inhibitor guselkumab (approved by the Food and Drug Administration for treating moderate to severe plaque psoriasis and psoriatic arthritis) but cost and effectiveness can be a factor. Although studies have shown efficacy, biologics as treatments for PPP are “hit or miss,” Dr. Hsu said.
Regarding use of systemic therapies, Dr. Hsu cautioned against using them to treat plaque-type psoriasis. “We always learn, don’t use a systemic steroid like prednisone to treat psoriasis because it helps, but it comes back with a vengeance,” she said. “Sometimes when you treat plaque-type psoriasis with prednisone, it could come back with a vengeance, and it can come back as generalized pustular psoriasis.”
For patients with GPP, “you need a quick fix” because of the painful symptoms associated with the disease, Dr. Hsu said. In this case, she recommended cyclosporine and said she would avoid prescribing topical medications. “You’re going to have to give an oral drug because usually when we’re seeing somebody with GPP, they’re either a hospital consult or they just walked in the door,” she said. After prescribing cyclosporine, you would transition to another treatment like a biologic “as quickly as you can” with the knowledge that the biologic “may or may not work.”