Fernandez, Anthony P

Importance Pyoderma gangrenosum (PG) is a rare neutrophilic dermatosis characterized by sterile ulcerative skin lesions. Multiple comorbidities and clinical features have been associated with PG, but no standardized guidelines exist for classifying PG phenotypes. Objective To develop an expert-established classification framework for PG phenotypes to inform treatment guidelines and future research endeavors. Evidence Review In this modified Delphi consensus study that included 23 board-certified dermatologists and Medical Dermatology Society members with expertise in PG, panelists completed 5 rounds of anonymous, iterative online surveys that were administered from December 2023 through July 2025. Before the beginning of the consensus exercise, a literature review was performed by nonvoting researchers to summarize existing data on PG clinical associations and comorbidities. A PubMed search from inception to September 2023 identified observational studies, narrative reviews, systematic reviews, and meta-analyses describing PG clinical associations and comorbidities that were published in English. Experts indicated their agreement with proposed PG phenotypes and disease modifiers with a consensus threshold of 70% or greater. Anonymous comments and aggregated results were presented in each subsequent round. In the final round, a framework of PG phenotypes and disease modifiers was proposed for agreement. Findings Twenty-three board-certified dermatologists and Medical Dermatology Society members with expertise in PG completed 5 rounds of iterative surveys. Consensus was reached on the final set of PG phenotypes and disease modifiers, with 83% of experts in agreement. PG phenotypes were overall classified into 2 major groups: PG with autoinflammatory syndromes and nonsyndromic PG. Nonsyndromic PG included 4 phenotypes: inflammatory bowel disease–associated PG, PG in association with hematologic cancers and blood dyscrasias, drug-induced PG, and other (including idiopathic) PG. Disease modifiers of PG phenotype presentations included involvement of special sites (head/neck, genitals, or peristomal skin) and extracutaneous manifestations. Conclusions and Relevance This expert-established, descriptive framework provides a standardized classification system for distinct PG phenotypes and its modifiers. This nomenclature may inform upcoming clinical guidelines and allow for consistency in reporting epidemiological research and outcomes among patients with PG.

Abstract Dermatomyositis is driven by overactivation of type I and II interferons and other proinflammatory cytokines that signal via the JAK-STAT pathway. We conducted a 12-week, open-label study of brepocitinib, an oral TYK2/JAK1 inhibitor, in five adults with severe cutaneous dermatomyositis. Treatment was associated with rapid, clinically meaningful improvement in cutaneous disease activity. Single-cell and spatial transcriptomic profiling of lesional skin showed marked suppression of interferon-responsive pathways and inflammatory cell states by week 4. Together with findings from a Phase 3 randomized trial in DM patients with skin and muscle involvement (VALOR, NCT05437263 ), these data support TYK2/JAK1 inhibition as a promising therapeutic strategy for DM.

Abstract Objectives The lack of uniform terminology and abbreviations for anti-synthetase syndrome has led to significant challenges in research and clinical practice. This study aimed to establish an international consensus on a standardized nomenclature and abbreviation among a diverse group of global myositis experts and patient representatives. Methods This qualitative project was approved by the International Myositis Assessment and Clinical Studies Group (IMACS). Based on the outcomes of a literature review and preliminary survey, list of terms for nomenclature and abbreviations was finalized. Subsequently, two rounds of the Delphi survey were conducted among myositis experts and patient participants to ascertain current practices and preferences. Using Nominal Group Technique (NGT), the project steering committee developed a consensus nomenclature and abbreviation. Results A total of 241 and 132 myositis experts from six continents, 35 countries and 9 specialities participated in round 1 and round 2 of the Delphi survey, respectively. The results indicated a preference for the terms anti-synthetase syndrome, antisynthetase syndrome and anti-tRNA synthetase syndrome. The abbreviations ASS, ASyS and ASSD were most used, though ASS received notable disapproval. The steering committee, including twenty-five myositis experts and three patient representatives from diverse backgrounds and geographical locations, reached a consensus on ‘anti-synthetase syndrome’ as the preferred nomenclature and ASyS as the preferred abbreviation, with 100% and 93.1% votes, respectively. Conclusion The terms anti-synthetase syndrome and ASyS should be adopted as the standard nomenclature and abbreviation in both research and clinical practice. This standardization is expected to increase consistency within the literature.

ImportanceDirect immunofluorescence (DIF) testing has been an important ancillary tool for the diagnosis of various inflammatory mucocutaneous conditions for more than 50 years. Current DIF test panels are based on historical clinical descriptions; few studies have rigorously addressed preanalytical, analytical, and/or postanalytical aspects, and even fewer have been replicated or validated. Recent unresolved key issues include whether DIF testing and test panels should be triaged or truncated based on clinical indication or histopathologic findings.ObjectiveTo assess levels of consensus regarding practical aspects of DIF testing among immunodermatology testing specialists in the US.Design, Setting, and ParticipantsUsing modified Delphi methods with a priori characterized criteria, a survey containing 54 statements pertaining to DIF testing was created and distributed to assess consensus. Statements not initially reaching consensus were discussed in 2 live virtual sessions, which were supplemented by relevant literature review and free-text survey comments. These statements were then reassessed in a second survey. Immunodermatology testing specialists in US academic institution–based and independent laboratories were invited based on serving as immunodermatology laboratory medical directors, authoring pertinent literature, or delivering relevant talks at major conferences or by referral. The first survey was conducted from January to February 2024, and the second survey was conducted from March to April 2024.Main Outcomes and MeasuresThe primary measured outcome was degree of consensus for various DIF testing practice, including DIF testing triage by histopathology/dermatopathology findings and DIF testing panel tailored truncations by clinical indication.ResultsA total of 23 respondents to the survey invitation had a mean (SD) of 18.5 (11.1) years and median (range) of 20.0 (1.5-46.0) years in immunodermatology laboratory practice. Consensus was achieved for 46 of 54 statements (85.2%) in the initial survey and for an additional 4 statements in the second survey (50 of 54 [92.6%]). Strong consensus was found against tailored truncation of DIF panel based on the clinical indication in the first survey round. The general acceptability of triaging specimens for DIF testing based on histopathology findings remained without consensus after both surveys.Conclusions and RelevanceOverall, participating US specialists in immunodermatology laboratory testing agreed on many practical aspects of DIF testing, including matters not queried previously. The findings also revealed areas of continued controversy and identified issues for prioritized future study.

SummaryBackground and aimsExtra‐intestinal manifestations (EIMs) are a common complication of inflammatory bowel diseases (IBD), affecting up to half of the patients. Despite their high prevalence, information on standardised definitions, diagnostic strategies, and treatment targets is limited.MethodsAs a starting point for a national EIM study network, an interdisciplinary expert panel of 12 gastroenterologists, 4 rheumatologists, 3 ophthalmologists, 6 dermatologists, and 4 patient representatives was assembled. Modified Delphi consensus methodology was used. Fifty‐four candidate items were derived from the literature review and expert opinion focusing on five major EIMs (erythema nodosum, pyoderma gangrenosum, uveitis, peripheral arthritis, and axial arthritis) were rated in three voting rounds.ResultsFor use in a clinical practice setting and as part of the creation of a prospective registry of patients with EIMs, the panel developed definitions for erythema nodosum, pyoderma gangrenosum, uveitis, peripheral arthritis, and axial arthritis; identified the appropriate and optimal subspecialists to diagnose and manage each; provided methods to monitor disease course; offered guidance regarding monitoring intervals; and defined resolution and recurrence.ConclusionsConsensus criteria for appropriate and optimal means of diagnosing and monitoring five EIMs have been developed as a starting point to inform clinical practice and future trial design. Key findings include straightforward diagnostic criteria, guidance regarding who can appropriately and optimally diagnose each, and monitoring options that include patient and physician‐reported outcomes. These findings will be used in a national multicenter study network to optimise the management of EIMs.