Clinical Features, Treatment Effectiveness and Long-Term Outcomes in Children with Moderate-to-Severe Generalized Pustular Psoriasis: A Retrospective Cohort Study.

Background: Generalized pustular psoriasis (GPP) is a rare inflammatory skin disorder, frequently accompanied by systemic inflammatory manifestations. Pediatric GPP presents unique clinical features and requires tailored treatment approaches. However, real-world data on pediatric moderate-to-severe GPP remain limited. Objective: To describe the clinical profiles of pediatric moderate-to-severe GPP, evaluate the effectiveness of various treatments, and their impact on disease recurrence. Methods: This retrospective observational study enrolled pediatric moderate-to-severe GPP inpatients in our department from March 2017 to February 2024. Clinical characteristics, treatment regimens, and recurrence were collected and analyzed using electronic medical records and follow-up data. Results: 61 pediatric patients were included, with a male-to-female ratio of 1.54: 1, an average age of 10.6±3.2 years. Concomitant symptoms were present in 93.4% of patients, including pruritus, fever, and skin pain. Common comorbidities included hypoproteinemia, anemia, and hyperlipidemia. Over 80% of patients exhibited elevated inflammatory markers, including IL-6, TNF-α. GPP with psoriasis vulgaris (PV) and without PV had similar clinical presentations. Regarding treatment outcomes, compared with traditional drugs, biologics significantly reduced both hospitalization time (6.0 days vs 8.0 days, P=0.002) and pustule clearance time (3.0 days vs 7.0 days, P=0.013), with a lower incidence of adverse events. Post-discharge follow-up data on annual flare indicated the biologics group was associated with fewer annual flares (0 vs 0.3 per person-year, P=0.052) and lower recurrence rate (21.1% vs 60.0%, P=0.034), compared with the traditional drugs group. Furthermore, serum proteomic analysis revealed significantly elevated IL-17 level and activation of the IL-17 signaling pathway in pediatric GPP compared with healthy controls, elucidating the mechanism underlying the high effectiveness of biologic-targeted therapies. Conclusion: For moderate-to-severe pediatric GPP, biologics exhibit faster effectiveness and better safety than traditional systemic drugs. Specifically, biologics can significantly reduce hospitalization time and pustule clearance time, and decrease disease recurrence.