ABSTRACT
Importance: Generalized pustular psoriasis (GPP) lacks internationally accepted definitions and diagnostic criteria, impeding timely diagnosis and treatment and hindering cross-regional clinical and epidemiological study comparisons. Objective: To develop an international consensus definition and diagnostic criteria for GPP using the modified Delphi method. Evidence Review: The rarity of GPP presents a challenge in acquiring comprehensive published clinical data necessary for developing standardized definition and criteria. Instead of relying on a literature search, 43 statements that comprehensively addressed the fundamental aspects of the definitions and diagnostic criteria for GPP were formulated based on expert reviews of 64 challenging GPP cases. These statements were presented to a panel of 33 global GPP experts for voting, discussion, and refinements in 2 virtual consensus meetings. Consensus during voting was defined as at least 80% agreement; the definition and diagnostic criteria were accepted by all panelists after voting and in-depth discussion. Findings: In the first and second modified Delphi round, 30 (91%) and 25 (76%) experts participated. In the initial Delphi round, consensus was achieved for 53% of the statements, leading to the approval of 23 statements that were utilized to develop the proposed definitions and diagnostic criteria for GPP. During the second Delphi round, the final definition established was, "Generalized Pustular Psoriasis is a systemic inflammatory disease characterized by cutaneous erythema and macroscopically visible sterile pustules." It can occur with or without systemic symptoms, other psoriasis types, and laboratory abnormalities. GPP may manifest as an acute form with widespread pustules or a subacute variant with an annular phenotype. The identified essential criterion was, "Macroscopically visible sterile pustules on erythematous base and not restricted to the acral region or within psoriatic plaques." Conclusions and Relevance: The achievement of international consensus on the definition and diagnostic criteria for GPP underscores the importance of collaboration, innovative methodology, and expert engagement to address rare diseases. Although further validation is needed, these criteria can serve as a reference point for clinicians, researchers, and patients, which may contribute to more accurate diagnosis and improved management of GPP.
Subject(s)
Antibodies, Monoclonal, Humanized/administration & dosage , Psoriasis/drug therapy , Antibodies, Monoclonal, Humanized/adverse effects , Dose-Response Relationship, Drug , Double-Blind Method , Humans , Male , Middle Aged , Placebos/administration & dosage , Placebos/adverse effects , Psoriasis/diagnosis , Severity of Illness Index , Treatment OutcomeABSTRACT
BACKGROUND: Oral methotrexate (MTX) has been a first line systemic agent in the treatment of chronic plaque psoriasis (CPP) for more than 50 years. Parenteral MTX, administered as a subcutaneous (SC) injection has gained favour in recent years. The effectiveness of SC MTX has been proven in rheumatological conditions but there has been no assessment of its role in CPP. METHODS: We retrospectively reviewed case notes of 85 patients prescribed SC MTX for psoriasis in three dermatology centres in the UK (Betsi Cadwaladr University Health Board, Western Infirmary, Glasgow, and Salford Royal NHS Foundation Trust). Audit department approval was sought and granted. RESULTS: A total of 85 patients (44 male; 41 female; age range 14 - 78 years, mean 44 years; 79 Caucasian, 6 Asian) with CPP were identified. The average duration of psoriasis was 19 years [range 3 - 60 years]. Co-morbidities included depression, diabetes mellitus, hypertension, epilepsy, obesity, ischaemic heart disease, and hyperlipidaemia; 29 patients had no associated co-morbidities. Psoriatic arthritis was noted in 18 patients. Previous treatments included phototherapy (both narrow band ultraviolet B [TLO1] and psoralen and ultraviolet A [PUVA])(n=60), oral MTX (n=82), ciclosporin (n=37), acitretin (n=19), fumaric acid esters (n=20), hydroxycarbamide (n=6), mycophenolate mofetil (n=2), and repeated in-patient admissions (n=2). Oral MTX was stopped due to nausea (n=43), ineffectiveness (n=13) or partial response (n=11), headache (n=3), increased liver enzymes (n=2), and lethargy (n=2). The median number of systemic agents used prior to SC MTX was 3 (mean 2.65, range 1 to 6 agents). The weekly dose of SC MTX varied between 7.5mg to 30 mg (mean 18.5mg, median 20mg) and had been used for 2 months to 67 months (mean 14 months; median 9 months). Folic acid supplementation was used in every patient. The patients were reviewed between 6 weeks to 3 months once treatment was fully established. Using a pre-determined "adjective list" (where specific adjectives were used to denote those who responded or did not respond to treatment), patients were classified as "responders" (n=59) or "non-responders" (n=26). CONCLUSION: This study suggests that SC MTX is an effective option in patients with CPP who have failed oral MTX and could be a worthwhile consideration prior to commencement of a biologic agent. Furthermore, the SC route may be a viable first choice of MTX administration. A randomised controlled trial comparing oral and SC MTX is required to validate these findings.
