Supplementary Material for: Clinical Features and Long-Term Outcomes in 109 Pediatric Generalized Pustular Psoriasis

Background: Pediatric-onset generalized pustular psoriasis (PGPP) is a rare inflammatory disorder characterized by recurrent flares and challenging management. This study aims to review the clinical features, flare patterns, and treatment options.
Methods: We analyzed PGPP patients diagnosed at Beijing Children’s Hospital from 2006 to 2023 who had complete medical record. Data on clinical characteristics, flare numbers and flare duration were collected through medical record and telephone survey. The flare frequency was calculated by dividing the flare numbers by the years in each age range. Flare duration was categorized as ≤4 weeks or >4 weeks. In addition, we investigated the factors associated with flare frequency in PGPP patients.
Results: A total of 109 patients with PGPP were included in the study, with a follow-up duration ranging from 1.90 to 22.80 years. The median age of onset was 6.00 years, with a higher prevalence in males (73, 66.97%). Most patients (55, 50.46%) experienced their first flare between the ages of 7 and 12 years. A total of 45 patients (41.28%) had history of psoriasis vulgaris (PV), 16 (14.68%) had history of acrodermatitis continua of Hallopeau (ACH), and 4 (3.67%) had history of psoriatic arthritis (PsA). Respiratory infection was the most common trigger, affecting 35 patients (32.11% of cases). The annual flare frequency was 0.68. The frequency and duration of flares showed a decreasing trend with increasing age. Earlier onset age is associated with a higher annual flare frequency. Before 2020, conventional therapies were most commonly used, with acitretin used in 67 patients (61.47%). Following 2020, secukinumab became the most often used medication (44 patients, 40.37%).
Conclusion: PGPP exhibits a trend toward flare decrease with age, yet recurrence remains common. Earlier onset age may be associated with higher flare frequency. At present, biologic agents are the main treatment. These findings provide new insights into PGPP.