Abstract
IMPORTANCE
Standard morphological terminology and definitions are vital for identification of lesion types in the clinical trial setting and communication about the condition. For hidradenitis suppurativa (HS), morphological definitions have been proposed by different groups, representing various regions of the world, but no international consensus has been reached regarding such definitions. A lack of globally harmonized terminology and definitions may contribute to poor-quality data collection in clinical trials as well as poor communication among clinicians, investigators, and patients.
OBJECTIVE
To establish and validate consensus definitions for typical morphological findings for HS lesions.
METHODS
This study was conducted from August 2019 to August 2020. A Delphi study technique was used to assess agreement and then resolve disagreement on HS terminology among international experts. After an initial preparation phase, the process consisted of 3 rounds. In each round, participants reviewed preliminary definitions and rated them as “keep, with no changes,” “keep, with changes,” or “remove.” Eight HS primary lesions, including papule, pustule, nodule, plaque, ulcer, abscess, comedo, and tunnel, were selected because they are most frequently used in HS clinician-reported outcome measures. The initial definitions were based on extant literature, and modifications were made between rounds based on qualitative thematic analysis of open-ended responses or discussion. Consensus was defined as greater than 70% to accept a definition. Consensus stability across rounds was defined as less than 15% change in agreement. Reliability was evaluated using the Gwet agreement coefficient. Validation was based on assessment of face validity and stability across rounds.
RESULTS
A total of 31 experts participated. All 8 HS primary lesion definitions achieved greater than 70% consensus by Delphi round 3. Stability was achieved for papule, pustule, and abscess. The Gwet agreement coefficient increased from 0.49 (95% CI, 0.26–0.71) in round 1 to 0.78 (95% CI, 0.64–0.92) in round 3. Face validity was supported by expert endorsement to keep terms in survey responses. Previously unmeasured variation among clinicians’ definition of tunnels was identified, and consensus was achieved.
CONCLUSIONS AND RELEVANCE
An international group of experts agreed on definitions for morphological features of HS lesions frequently included in HS clinical trials. These international consensus terms and definitions are needed to support consistency of lesion identification and quantification in clinical trials.
Hidradenitis suppurativa (HS) is a chronic inflammatory dermatosis manifesting in painful nodules, abscesses, and malodorous draining tunnels with a predilection to flexural regions.1 Hidradenitis suppurativa is relatively unique among inflammatory dermatoses because the disease can concurrently manifest as distinct morphological structures (pustules, nodules, abscesses, tunnels, plaques, ulcers, hypertrophic scarring, and comedones).2,3
The development of a standardized HS nomenclature is a priority in line with the goals of the Hidradenitis Suppurativa Core Outcomes Set International Collaboration4 in allowing for clear unambiguous definitions of the clinical manifestations of disease. Consistent definitions of cutaneous lesions improve reliability and reproducibility of clinical and translational research and accurate and precise communication between clinicians.5,6 They also facilitate the reliable comparison of clinical trial data on the basis of disease characteristics and the development of phenotype classifications in the search for personalizedtreatment.7 As a highly visual and descriptive specialty, standardized nomenclature for the description of cutaneous lesions is well established and frequently updated.8 However, the unique structures found with HS (eg, tunnels, double-ended comedones) have no consistent or widely accepted definitions.2,3
A number of glossaries have been developed through European consensus2,3,9,10 to standardize the HS nomenclature. However, no single glossary has yet to reach widespread global agreement or use. In addition, the development of such definitions requires the involvement of multiple stakeholders, because HS can often be managed by a multidisciplinary care team.11 A standardized HS morphological nomenclature needs to be appropriate for use by dermatologists, wound care specialists, and surgeons alike, while not deviating from the standard nosology of dermatological lesions. The aim of this study was to establish valid international consensus definitions for morphological features of HS lesions into a global HS glossary through a modified Delphi-consensus exercise.
Methods
Study Design
The Delphi technique was used to seek the opinion of a group of international experts from 9 countries (Australia, Canada, Chile, Denmark, France, Germany, Italy, the UK, and the US) to assess the extent of agreement and to resolve disagreement on an issue. This study was conducted from August 2019 to August 2020 and was overseen by 5 HS physician-investigators (J.W.F., M.A.L., N.G., A.A., and J.S.K.). This research was approved by the institutional review board of Penn State University College of Medicine and conducted under the terms of the Declaration of Helsinki.12 All participants provided informed consent to take part at the beginning of the study.
International Expert Panel
Sampling for the panel of expert group members was purposeful to ensure that invited participants met the inclusion criteria. Purposeful sampling was directed by the steering committee, who oversaw the consensus study and leveraged their networks to generate a list of potential participants. Inclusion criteria for participation consisted of being fluent English speakers and actively conducting clinical research in HS. Active research was required and defined as at least 1 HS-related publication in the previous 3 years as identified through PubMed, EMBASE, and Web of Science using the terms hidradenitis suppurativa and acneinversa in September 2019. Individual case reports were not considered. Those who did not meet the inclusion criteria were excluded. Network sampling, which entails referral of new participants by current participants, was used to further expand the expert group membership to ensure diverse representation of multiple nations, given the goal of generating international consensus. This study aimed to have a minimum of 12 respondents, because this is considered sufficient to enable achievement of consensus.13 A dropout rate of 20% was expected during the 3 rounds; thus, this study aimed to recruit a minimum of 15 expert group members.
Delphi Exercise
The Delphi process consisted of 3 rounds (Figure 1). The preparation phase involved identification of existing definitions for typical HS lesions, including papule, pustule, nodule, plaque, ulcer, abscess, come do, and tunnel, in the peer-reviewed literature. In round 1, an online survey was sent to expert group members on October 29, 2019. The survey was administered through the secure web application REDCap14 and included a summary of the terms and existing definitions in HS (eTable 1 in the Supplement). Participants were asked to rate each term and its proposed definition as “keep, with no changes,” “keep, with changes,” or “remove” A free-text response was available for each term and its proposed definition, with which participants could elaborate or explain their responses. This feedback was analyzed using established thematic analysis methodology,15 and the results were used to revise terms and definitions.
Figure 1.
Flow Diagram Illustrating the 3 Survey Rounds of the Delphi Study
Round 1 included 27 participants. Four additional participants were recruited between rounds 1 and 2, resulting in 31 participants in round 2. One eligible response was excluded in round 3 because eligibility could not be confirmed, resulting in 30 eligible responses.
The round 1 frequency statistics and qualitative results were presented to the 30 members of the expert group during an in-person meeting (Detroit, Michigan, November 1–2, 2019). The roundtable discussion was mediated by one of us (J.W.F.). Eight HS primary lesions in the most commonly used clinical outcome measures (Hidradenitis Suppurativa Clinical Response [HiSCR],16 International Hidradenitis Suppurativa Severity Score System [IHS4],9 and modified Sartorius score6) were taken as a starting point for the meeting discourse. The discussion focused on experts’ real experience in the identification and classification of HS primary lesions, as well the identification of rules and structures in the classification of HS lesions, which should be carried forward to further Delphi rounds.
In rounds 2 and 3, expert group participants received a survey with revised definitions and a summary of the group’s collective responses on previous rounds. Participants were asked to reconsider the term and definitions as well as their responses. Free text from each previous round was used to inform changes to subsequent rounds. The round 2 survey was sent on January 20, 2020, and electronic reminders were sent weekly for 4 weeks. Round 2 asked participants to rate the definitions “keep, with no changes,” “keep, with changes,” or “remove.” The round 3 survey was sent on April 13, 2020, and electronic reminders were sent weekly for 4 weeks. Round 3 presented only the options to “accept” or “not accept.”
Data Analysis
Qualitative data from surveys and the roundtable discussion were reviewed and the data were coded by 2 authors (J.W. F. and J.S.K.) using the constant comparative method to identify themes.15 Qualitative analysis was conducted after each round so themes could inform subsequent survey rounds. Descriptive statistics were used to describe group responses to each statement in all 3 rounds. Consensus was defined as more than 70% of participants agreeing/strongly agreeing or disagreeing/strongly disagreeing with a statement. This level of agreement has been considered appropriate in previous Delphi studies.17 Agreement was taken as a “keep with no changes” or “accept” response in round 3. Disagreement was taken as “keep with changes,” “remove,” or “not accept” responses in round 3. Stability was taken as a change of 15% or less in participant responses when there was consensus.18 The Gwet agreement coefficient was used to quantify the strength of consensus agreement for rank-type responses of the proposed definitions.19 Face validity was based on the high acceptance of the terms and definitions by the expert group, who represent the users of the terms.20 Quantitative analyses were conducted using SAS, version 9.4 (SAS Institute Inc).
Results
The expert group consisted of 31 participants, including dermatologists, surgeons, and translational scientists, all with clinical exposure to HS, and represented 9 countries and 4 continents. The response rate was 27 of 30 (90.0%) in round 1, with network sampling adding 4 additional participants for the second and third rounds.
Most of the expert group participants completed round 1 (20 of 27 [74.1%]), round 2 (25 of 31 [80.6%]), and round 3 (23 of 31 [74.2%]); 17 expert group participants (54.8%) responded to all rounds. A total of 30 physicians participated in the in-person discussion after round 1. A schematic representation of the modified Delphi process is presented in Figure 1.
The central tenets (a product of the in-person discussions of the expert group) used to guide the development of morphological definitions in HS included the following:
To describe HS lesions based on the morphology observed rather than presumptions of lesion contents or histological definitions (which the expert group termed the rule of Tan, named for J.T., who observed that the definitions should be based on clinical examination findings rather than presumed/assumed findings that could only be validly noted on imaging or histological findings).
To implement existing terms and definitions for dermatological lesions, with additional descriptors for HS-specific lesions. The 2016 International League of Dermatological Societies’ revised glossary was agreed on as a foundation for discussion and development of definitions.8
To develop terminology that may be implemented across disciplines of clinicians (eg, dermatologists, gynecologists, surgeons).
Terms and definitions should be exclusive of each other to prevent misclassification.
All sizes in these definitions represent diameter as assessed by visual inspection, palpation, or whichever is greater.
The Table shows a summary of the morphological terms and definitions. The number of statements where consensus was achieved improved from round 1 to round 3. In round 1,5 of 8 statements (62.5%) were rated as “accept.” In round 2, 3 of 8 statements (37.5%) were rated as “accept,” which rose to 8 of 8 (100%) in round 3. Stability in consensus was achieved between rounds 1 and 2 as well as rounds 2 and 3 for papule, ulcer, and abscess. The Gwet agreement coefficient improved from 0.49 (95% CI, 0.26–0.71) in round 1 to 0.78 (95% CI, 0.64–0.92) in round 3, indicating strong agreement.19 The proportion of participants that reported “do not accept” (ie, disagreement) to each statement in round 3 is presented in eTable 2 in theSupplement. Validity of the responses were evaluated; face validity was achieved through the participation of experts with clinical research experience in the expert group and the high agreement (Table) supporting the relevance of the definitions. Stability of consensus agreement was achieved from rounds 2 to 3 for papule, abscess, and ulcer; however, it was not achieved for the remaining terms.
Table.
Definitions for Hidradenitis Suppurativa Morphological Terms From Delphi Process and Achieving Consensus
| HS glossary term | Proportion of participants agree with definitionsa | Final definitions | Modification | ||
|---|---|---|---|---|---|
| Round 1 (n = 20) | Round 2 (n = 25) | Round 3 (n = 23) | |||
| Papule | 14 (70.0)b | 19 (76.0)b,c | 19 (82.6)b,c | A solid, palpable lesion ≤1 cmd | Inflammatory papule: tender and/or erythematous |
| Noninflammatory papule: nontender, nonerythematous | |||||
| Pustule | 14 (70.0)a | 16 (64.0) | 21 (91.3)a | A superficial circumscribed lesion that contains opaque fluid (pus) ≤1 cm | NA |
| Nodule | 11 (55.0) | 12 (48.0) | 22 (95.7)a | A solid, spherical, palpable lesion >1 cm | Inflammatory nodule: tender and/or erythematous |
| Noninflammatory nodule: nontender, nonerythematous | |||||
| Eroded nodule: a friable nonepithelialized nodule | |||||
| Plaque | 11 (55.0) | 9 (36.0) | 21 (91.3)a | A variably shaped, nonspherical, palpable lesion >1 cm | Inflammatory plaque: tender and/or erythematous |
| Noninflammatory plaque: nontender, nonerythematous, may be a type of scar | |||||
| Ulcer | 14 (70.0)a | 21 (84.0)a,b | 22 (95.7)a,b | Full-thickness loss of epidermis and at least a portion of the dermis | NA |
| Abscess | 14 (70.0)a | 19 (76.0)a,b | 21 (91.3)a,b | A tender, fluctuant (compressible), palpable lesion, with erythema | NA |
| Comedo | 15 (75.0)a | 13 (52.0) | 21 (91.3)a | Dilated skin opening with keratinous debris | Double comedo: interconnected comedones |
| Tunnel | 11 (55.0) | 16 (64.0) | 19 (82.6)a | A linear tract that may open onto the skin surface | Draining tunnel: drainage expressed at rest or with compression of surrounding structures |
| Nondraining tunnel: compression of surrounding structures does not elicit drainage of contents | |||||
| Fistula: reclassify tunnel as fistula if connects from the skin surface to a hollow organ (eg, bowel, vagina, bladder) | |||||
| Agreement coefficient (95% CI) | 0.49 (0.26–0.71) | 0.56 (0.44–0.68) | 0.78 (0.62–0.94) | NA | NA |
Abbreviation: NA, not applicable.
Unless otherwise indicated, data are expressed as number (percentage) of participants.
Consensus was achieved when 70% or more of participants agreed with a definition.
Stability was achieved, defined as a change in response of 15% or less.
All sizes represent diameter as assessed by visual inspection, palpation, or whichever is greater.
Discussion
Commonly accepted and unambiguous definitions of key HS lesions are vital to facilitate communication for HS clinical care, clinical trials, and research. Hidradenitis suppurativa clinical trials are an international effort, so global input and agreement on HS terminology are crucial. Comparison of the terms and definitions from this study with a recent proposed set of definitions by Daxhelet et al10 highlights important similarities and differences. There were similarities for papule, pustule, nodule, abscess, and comedo. However, our study developed an acceptable definition for the term tunnel, which is a core term used in clinician-reported outcome measures (HiSCR16 and IHS49). The definitions by Daxhelet et al10 were voted and commented on by 81 physicians at the Fifth Conference of the European HS Foundation in 2016; however, the modified Delphi process used in the present report is a more robust approach to confirm global consensus than one-time voting.17,18 In addition, the definitions from this study are consistent with the International League of Dermatological Societies definitions, which is important to maintaining interpretability within the wider dermatological and medical community. This supports the aim of these definitions to support multidisciplinary communication and coordination of patient care.
In this project, consensus definitions were developed for 8 key primary HS lesions: papule, pustule, nodule, plaque, ulcer, abscess, comedo, and tunnel. The consensus definition of a papule is “a solid, palpable lesion ≤1 cm.” This is a widespread definition for a papule due to any condition and the maximal 1-cm size is used to distinguish it from larger inflammatory nodules. Because some outcome measures distinguish inflammatory and noninflammatory papules,16,21,22a modifier was developed for these descriptions based on tenderness and erythema. The consensus definition for a pustule is “a superficial circumscribed lesion that contains opaque fluid (pus) ≤1 cm” Earlier definitions did not include a size marker for pustule, but this definition distinguishes them from larger lesions containing pus, such as abscesses.
Abscess was defined by consensus as “a tender, fluctuant/compressible, palpable lesion, with erythema.” Although usually considered a diagnosis rather than a primary morphological feature of an HS lesion, abscess was included in the list of HS primary lesions because it is a core component of IHS4 and HiSCR.9,16,23 Importantly, the HiSCR is the only US Food and Drug Administration-qualified outcome measure for HS clinical trials. During this study, some participants believed that the definition of abscess should contain “presumed to be filled with pus,” to distinguish from an inflamed cyst and hematoma. However, this statement was excluded in the final definition that reached consensus, because it describes a speculation or requires a procedure to determine the contents, rather than a morphological description of a lesion.
The consensus definition of a nodule is “a solid, spherical, palpable lesion ≥1 cm” This is similar to extant definitions of a nodule. A nodule is separated from a papule by its larger size and from a plaque by its spherical shape. The inflammatory and noninflammatory descriptors can again be used based on tenderness and erythema. In addition, this study defined a third type of nodule, the “eroded nodule,” as ”a friable nonepithelialized nodule.” This is in contrast to the recent glossary terms proposed by Daxhelet et al10 that included “multiple pyogenic granulomas”; however, this term implies knowledge of the histological findings and a diagnosis, rather than a morphological description.
The definition for the term tunnel generated the most discussion. It became apparent that some experts use different terms to describe these linear tracts (Figure 2). A case in point is the description of subepithelial tracts, variously known as tunnels, fistulae, or sinus tracts.2,3,9 For some, sinus tracts and fistulae denote very different structures24; however, these terms have been used by others interchangeably in the setting of HS.3 The term tunnel has been proposed as a unique descriptor of these structures2,3,9 but does not discriminate among tunnels with a single opening that ends blindly, skin-to-skin tunnels with 2 skin openings, or tunnels that connect a hollow organ to the skin surface (commonly termed fistula). Some respondents use the term sinus tract to denote a blind cavity with a single opening to the skin surface and skin fistula to denote a tunnel with 2 or more connections to the skin surface. In contrast, there was a concern that the term fistula has a different meaning in other disciplines and implies a communication between 2 organs (eg, bowel and skin), usually requiring imaging for definitive diagnosis. A diagram similar to Figure 2 was included in the Delphi study to help clarify the terms and definitions as well as their modifications. There was consensus that a tunnel is “a linear tract that may open onto the skin surface.” Some tunnels do not have appreciable openings onto the skin surface at the time of examination (Figure 2). These lesions may be difficult to distinguish from others by clinical examination, such as an abscess, although tunnels are expected to be more linear. The goal of this work was to develop lesion definitions based solely on clinical examination results; however, future glossaries may add precision and accuracy by combining clinical and imaging findings. Last, the definitions related to tunnels also clarify draining vs nondraining tunnels, which is crucial because the former is counted in the HiSCR and IHS4, whereas the latter is not.9,16
Figure 2.
Schematic Representation of the Hidradenitis Suppurativa Lesion Types Described in This Study
The lesions defined in this study are illustrated herein and include papule, pustule, nodule, plaque, ulcer, abscess, comedo, and tunnel. As illustrated in panel H, tunnels may include connection to a hollow organ (eg, bladder, intestine) (A), blind ending (B), 2 skin-to-skin openings (C), and no opening to the surface (D). The original artwork was created by Bradley Winters, Penn State University.
A novel term introduced in this glossary is plaque, which is defined as “a variably shaped, nonspherical, palpable lesion >1 cm,” and may also be described as inflammatory and noninflammatory based on tenderness and erythema. Plaques are differentiated from nodules by being irregularly shaped and nonspherical. Long-standing terms, including ulcer and comedo (with its variants), are consistent with the International League of Dermatological Societies definitions.
Strengths and Limitations
This Delphi consensus focused on 8 primary morphological features of HS lesions and drew on an international network of HS clinician-researchers. The size and composition of the expert panel may not be representative of all countries and may reduce the generalizability of the results. Nevertheless, one of the strengths of this report is that the final sample size was approximately double the minimum sample size planned for the project. Also, the response rates for each round of the study were substantial at 74.1% for round 1, 80.6% for round 2, and 76.7% for round 3. Consensus was achieved for all terms and definitions, yet stability of consensus was achieved for 3 of the terms, so it is not known how stable the consensus would be for the remaining items, especially for nodule and plaque, which had the largest change in agreement. Given the global scale on which this field operates, the Delphi consensus technique, which can be conducted anonymously online, was able to identify areas of consensus and highlight areas where further exploration is needed. Areas that were not addressed in this study include secondary structures reported in other definition lists10 and combinations of multiple morphological features. To address the limitation of only 1 surgeon in the expert group, future HS expert participants will include additional surgeons. The next step is to develop consensus on secondary lesions, how morphological features of lesions can arise in combination, and how they should be accounted for in existing outcome measures that include abscesses, nodules, and draining tunnels. We acknowledge the need for validation to determine the utility and reliability of the tunnel definition in the research and real-world setting. Future studies are needed to investigate how these terms and definitions affect the reliability of clinician-reported outcomes, to further establish the validity of the definitions, and to identify representative clinical images as examples of each lesion type.
Hidradenitis suppurativa clinical trials are increasingly global, so widespread adoption of consistent definitions is needed. Standardization of morphological definitions is vital to achieve high-quality data in future global clinical trials. Inconsistency in lesion terminology may affect lesion counts in clinical trials, contributing to invalid or poorly reliable data. The Delphi method with international participants in this study supports face validity for adoption in international trials. Prior studies were limited by a lack of global participation or less robust methods.2,3,9,10 This study included qualitative methods that guided the development of the proposed definitions through the Delphi process. Ensuring definitions conform to the lived experience of a variety of international experts supports the strong face validity of these definitions.
Conclusions
The morphological definitions of HS lesions, presented herein, are the first, to our knowledge, to gain consensus across a global population of HS experts. They are useful in promoting consistent nomenclature among clinicians and investigators as well as presenting a global starting point for the consistent identification of lesions in clinical trials. Future work is needed to address issues such as definitions of secondary and combined lesions, to validate the proposed definitions in the setting of clinical trials, and to investigate the effect on the reliability of clinician assessments.
Supplementary Material
Key Points.
Question
Can morphological definitions of lesions in hidradenitis suppurativa (HS) be harmonized by a panel of international experts in this disease?
Findings
For this consensus statement, qualitative methods and a 3-round modified Delphi-consensus exercise among 31 experts produced acceptable agreement on morphological definitions across 8 primary HS lesion types. These definitions were validated using both qualitative and quantitative methods.
Meaning
The presented consensus morphological definitions are valuable as guidance for reliable lesion identification and terminology in clinical trials and in practice.
Funding/Support:
This study was supported by an unrestricted grant of $10,000 for this project from AbbVie Inc (Canada) and grant UL1 TR002014 for the use of REDCap from The Penn State Clinical & Translational Research Institute, Pennsylvania State University CTSA, National Institutes of Health, National Center for Advancing Translational Sciences.
Conflict of Interest Disclosures:
Dr Frew reported conducting advisory workfor Janssen Global Services, LLC, Boehringer-Ingelheim International GmbH, Pfizer, Inc, Kyowa Kirin Co, Ltd, LEO Pharma A/S, Regeneron Pharmaceuticals Inc, and UCB SA; participating in trials for UCB SA; and receiving research support from Ortho Dermatologics. Dr Lowes reported serving on the advisory boards for AbbVie Inc, Janssen Global Services, LLC, and Viela Bio and consulting for Almirall, SA, BSN, Incyte, Janssen Global Services, LLC, Kymera Therapeutics, and XBiotech USA, Inc. Dr Goldfarb reported participating in clinical trials with ChemoCentryx, Inc, AbbVie Inc, and Pfizer, Inc. Dr Piguet reported undertaking advisory work for Pfizer, Inc, AbbVie Inc, Janssen Global Services, LLC, UCB SA, Novartis AG, Almirall, SA, and Celgene Corporation; receiving honoraria from Kyowa Kirin Co, Ltd; and a role as Department Division Director of Dermatology at the University of Toronto, receiving departmental support from AbbVie Inc, Bausch Health Companies Inc (formerly Valeant), Celgene Corporation, Janssen Global Services, LLC, LEO Pharma A/S, Elli Lilly and Company, NAOS, Novartis AG, Pfizer, Inc, Pierre Fabre Group, and Sanofi in the past 3 years. Dr Ingram reported serving as editor in chief of the British Journal of Dermatology; consulting for UCB SA, Novartis AG, Viela Bio, and Kymera Therapeutics; and receiving travel expenses and a speaker’s honorarium from UCB SA. Dr Jemec reported serving on the advisory boards (honoraria) of AbbVie Inc, ChemoCentryx, Inc, Coloplast Corp, Incyte, InflaRx NV, Novartis AB, Pierre Fabre Group, and UCB SA; serving as an investigator for AbbVie Inc, LEO Pharma A/S, Janssen-Cilag, Regeneron Pharmaceuticals Inc, Sanofi, AstraZeneca, and Novartis AG; serving as a speaker (honoraria) for AbbVie Inc, Boehringer-Ingelheim International GmbH, Galderma, and Merck Sharp & Dohme; and receiving unrestricted grants from AbbVie Inc, LEO Pharma A/S, and Novartis AG. Dr Tan reported serving on the advisory board of UCB SA and as an investigator for Incyte. Dr O’Brien reported serving on the advisory board of AbbVie Inc. Dr Zouboulis reported serving as consultant, advisor, and/or speaker for AbbVie Inc, Idorsia Pharmaceuticals Ltd, Incyte, InflaRx NV, Janssen Global Services, LLC, Novartis AG, Regeneron Pharmaceuticals Inc, and UCBSA and receiving relevant grants to departments from AbbVie Inc, InflaRx NV, NovartisAG, and UCB SA for participation as an investigator. Dr Alavi reported serving as a consultant and/or advisor and/or receiving research funding from AbbVie Inc, Galderma, Janssen Global Services, LLC, LEO Pharma A/S, Novartis AG, Sanofi-Aventis, Valeant, Boehringer-Ingelheim International GmbH, DS Biopharma Limited, Eli Lilly and Company, Glenmark, Incyte, Ilkos Therapeutic, Merck Serono, Pfizer, Inc, Regeneron Pharmaceuticals Inc, F Hoffman-LaRoche Ltd, Xenon, Kymera Therapeutics, Kyowa Kirin Co, Ltd, and XOMA Corporation. Dr Kirby reported serving on advisory boards for AbbVie Inc, Incyte, and Viela Bio; serving as a speaker for AbbVie Inc; and consulting for AbbVie Inc, ChemoCentryx, Inc, Incyte, Novartis AG, and UCB SA. No other disclosures were reported.
Role of the Funder/Sponsor:
The sponsors had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; preparation, review, or approval of the manuscript; and decision to submit the manuscript for publication.
Contributor Information
JohnW. Frew, Laboratory of Investigative Dermatology, The Rockefeller University, New York City, New York;.
Michelle Anne Lowes, The Rockefeller University, New York City, New York;.
Noah Goldfarb, Department of Internal Medicine, University of Minnesota, Minneapolis;; Department of Dermatology, University of Minnesota, Minneapolis; Department of Internal Medicine, Minneapolis VA Health Care System, Minneapolis, Minnesota; Department of Dermatology, Minneapolis VA Health Care System, Minneapolis, Minnesota;
Melissa Butt, Department of Dermatology, Penn State Milton S. Hershey Medical Center, Hershey, Pennsylvania;.
Vincent Piguet, Division of Dermatology, Department of Medicine, University of Toronto, Toronto, Ontario, Canada;; Division of Dermatology, Women’s College Hospital, Toronto, Ontario, Canada;
Elizabeth O’Brien, Division of Dermatology, Department of Medicine, University of Toronto, Toronto, Ontario, Canada;; Division of Dermatology, Women’s College Hospital, Toronto, Ontario, Canada;
John Ingram, Department of Dermatology and Wound Healing, Division of Infection and Immunity, Cardiff University, Cardiff, United Kingdom;.
Gregor B. E. Jemec, Department of Dermatology, Zealand University Hospital, Roskilde, Denmark;.
Jerry Tan, Department of Medicine, University of Western Ontario, Windsor, Ontario, Canada;.
Christos Zouboulis, Department of Dermatology, Dessau Medical Center, Brandenburg Medical School Theodor Fontane and Faculty of Health Sciences Brandenburg, Dessau, Germany;; Department of Venereology, Dessau Medical Center, Brandenburg Medical School Theodor Fontane and Faculty of Health Sciences Brandenburg, Dessau, Germany; Departments of Allergology, Dessau Medical Center, Brandenburg Medical School Theodor Fontane and Faculty of Health Sciences Brandenburg, Dessau, Germany; Department of Immunology, Dessau Medical Center, Brandenburg Medical School Theodor Fontane and Faculty of Health Sciences Brandenburg, Dessau, Germany;
Afsaneh Alavi, Department of Dermatology, Mayo Clinic, Rochester, Minnesota..
Joslyn S. Kirby, Department of Dermatology, Penn State Milton S. Hershey Medical Center, Hershey, Pennsylvania;.
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