Hidradenitis suppurativa (HS)/acne inversa is a debilitating chronic disease that remains poorly understood and difficult to manage. Clinical practice is variable, and there is a need for international, evidence-based and easily applicable consensus on HS management. We report here the findings of a systematic literature review, which were subsequently used as a basis for the development of international consensus recommendations for the management of patients with HS. A systematic literature review was performed for each of nine clinical questions in HS (defined by an expert steering committee), covering comorbidity assessment, therapy (medical, surgical and combinations) and response to treatment. Included articles underwent data extraction and were graded according to the Oxford Centre for Evidence-based Medicine criteria. Evidence-based recommendations were then drafted, refined and voted upon, using a modified Delphi process. Overall, 5310 articles were screened, 171 articles were analysed, and 65 were used to derive recommendations. These articles included six randomized controlled trials plus cohort studies and case series. The highest level of evidence concerned dosing recommendations for topical clindamycin in mild disease (with systemic tetracyclines for more frequent/widespread lesions) and biologic therapy (especially adalimumab) as second-line agents (following conventional therapy failure). Good-quality evidence was available for the hidradenitis suppurativa clinical response (HiSCR) as a dichotomous outcome measure in inflammatory areas under treatment. Lower-level evidence supported recommendations for topical triclosan and oral zinc in mild-to-moderate HS, systemic clindamycin and rifampicin in moderate HS and intravenous ertapenem in selected patients with more severe disease. Intralesional or systemic steroids may also be considered. Local surgical excision is suggested for mild-to-moderate HS, with wide excision for more extensive disease. Despite a paucity of good-quality data on management decisions in HS, this systematic review has enabled the development of robust and easily applicable clinical recommendations for international physicians based on graded evidence.

SummaryBackground A validated tool for the dynamic severity assessment of hidradenitis suppurativa/acne inversa (HS) is lacking. Objectives To develop and validate a novel dynamic scoring system to assess the severity of HS. Methods A Delphi voting procedure was conducted among the members of the European Hidradenitis Suppurativa Foundation (EHSF) to achieve consensus towards an initial HS Severity Score System (HS4). Strengths and weaknesses of HS4 were examined by a multicentre prospective study. Multivariate logistic regression, discriminant analysis and receiver operating characteristic curves, as well as examination for correlation (Spearman's rho) and agreement (Cohen's kappa) with existing scores, were engaged to recognize the variables for a new International HS4 (IHS4) that was established by a second Delphi round. Results Consensus HS4 was based on number of skin lesions, number of skin areas involved and Dermatology Life Quality Index (DLQI), and was evaluated by a sample of 236 patients from 11 centres. Subsequently, a multivariate regression model calculated adjusted odds ratios for several clinical signs. Nodules, abscesses and draining tunnels resulted as the scoring variables. Three candidate scores were presented to the second Delphi round. The resulting IHS4 score is arrived at by the number of nodules (multiplied by 1) plus the number of abscesses (multiplied by 2) plus the number of draining tunnels (multiplied by 4). A total score of 3 or less signifies mild, 4-10 signifies moderate and 11 or higher signifies severe disease. Cohen's kappa was fair (j = 0Á32) compared with Hurley classification, and moderate (j = 0Á49) compared with Expert Opinion.

Background: A needs assessment for patients with hidradenitis suppurativa (HS) will support advancements in multidisciplinary care, treatment, research, advocacy, and philanthropy.

Hidradenitis suppurativa (HS) is a chronic, inflammatory, debilitating skin disease. The aim of the study was to systematically review the literature and critically answer the question: In patients with HS, do cardiovascular risk factors appear at a significantly higher rate compared with controls? The main search was conducted in Medline, Embase and the Cochrane Central Register. Studies eligible for inclusion were of case-control, cross-sectional and cohort design, and included comparison of any cardiovascular risk factor(s) in patients with HS with those of control groups. An I(2) value > 50% was considered to show substantial heterogeneity. In this case, DerSimonian and Laird random-effect models were considered to compute pooled odds ratios (OR). Otherwise, a fixed-effects model was suitable. Nine studies, with 6174 patients with HS and 24 993 controls, were included. Significant association of HS with obesity [OR 3·45, 95% confidence interval (CI) 2·20-5·38, P < 0·001], central obesity (OR 2·97, 95% CI 1·41-6·25, P = 0·004), active smoking (OR 4·34, 95% CI 2·48-7·60, P < 0·001), history of smoking (OR 6·34, 95% CI 2·41-16·68, P < 0·001), hypertriglyceridemia (OR 1·67, 95% CI 1·14-2·47, P = 0·009), low high-density lipoprotein (HDL) (OR 2·48, 95% CI 1·49-4·16, P < 0·001), diabetes (OR 2·85, 95% CI 1·34-6·08, P = 0·007) and metabolic syndrome (OR 2·22, 95% CI 1·62-3·06, P < 0·001) was detected. Associations were significant both in population and hospital patients with HS, with hospital HS groups having uniformly higher ORs than the population HS groups. Causality could not be assessed. Heterogeneity was substantial in all analyses. This systematic review indicated that cardiovascular risk factors appear at a significantly higher rate in patients with HS compared with controls. The need for screening of patients with HS for modifiable cardiovascular risks is emphasized.

Summary Background Monitoring disease activity over time is a prerequisite for clinical practice and research. Valid and reliable outcome measurement instruments (OMIs) and staging systems provide researchers and clinicians with benchmark tools to assess the primary and secondary outcomes of interventional trials and to guide treatment selection properly. Objectives To investigate inter‐rater reliability and agreement in instruments currently used in hidradenitis suppurativa (HS), with dermatologists experienced in HS as the rater population of interest. Methods In a prospective completely balanced design, 24 patients with HS underwent a physical examination by 12 raters (288 assessments) using nine instruments. The results were analysed using generalized linear mixed models. Results For the staging systems, the study found good inter‐rater reliability for Hurley staging in the axillae and gluteal region, moderate inter‐rater reliability for Hurley staging in the groin and for Physician's Global Assessment, and fair inter‐rater reliability for refined Hurley staging and the International HS Severity Scoring System. For all the tested OMIs, the observed intervals for limits of agreement were very wide relative to the ranges of the scales. Conclusions The very wide intervals for limits of agreement imply that substantial changes are needed in clinical research in order to rule out measurement error. The results illustrate a difficulty, even for experienced HS experts, to agree on the type and number of lesions when evaluating disease severity. The apparent caveats call for global efforts, such as the HIdradenitis SuppuraTiva cORe outcomes set International Collaboration (HISTORIC) to reach consensus on how best to measure physical signs of HS reliably in randomized trials. What's already known about this topic? Without valid and reliable instruments to measure outcomes, researchers and clinicians lack the necessary benchmarks to assess primary and secondary end points of interventional trials properly. Hidradenitis suppurativa (HS) is a chronic inflammatory skin disease. Several outcome measure instruments exist for HS, but their validation is generally incomplete or of relatively low methodological quality. What does this study add? Using a prospective completely balanced design this study examined inter‐rater reliability with HS‐experienced dermatologists as the rater population of interest. The study did not find very good reliability for any included instrument or lesion counts. This study illustrates the difficulty in finding agreement on the type and number of HS lesions, even among experts. The results question whether physical signs are best measured by a traditional physician lesion count instrument. What are the clinical implications of this work? For staging, Hurley staging and physician global visual analogue scale proved to be acceptable instruments in terms of inter‐rater reliability. For the instruments designed to measure changes in health status, our study illustrates how difficult ...

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Patients with newly diagnosed HS and general patients with HS experienced a greater indirect burden than matched controls.

This paper is organized jointly by the European Academy of Dermatology and Venereology (EADV) Task Force (TF) on Quality of Life (QoL) and Patient‐Oriented Outcomes and the EADV TF on acne, rosacea and hidradenitis suppurativa (ARHS). The purpose of this paper was to present current knowledge about QoL assessment in HS, including data on HS‐specific health‐related (HR) QoL instruments and HRQoL changes in clinical trials, and to make practical recommendations concerning the assessment of QoL in people with HS. HS results in significant quimp that is higher than in most other chronic skin diseases. HS impact in published studies was assessed predominantly (84% of studies) by the Dermatology Life Quality Index (DLQI). There is a lack of high‐quality clinical trials in HS patients where HRQoL instruments have been used as outcome measures. One double‐blind randomized placebo‐controlled trial on infliximab with low number of participants reported significantly better HRQoL improvement in the treatment group than in the placebo group. Well‐designed clinical studies in HS patients to compare different treatment methods, including surgical methods and assessing long‐term effects, are needed. Because of lack of sufficient validation, the Task Forces are not at present able to recommend existing HS‐specific HRQoL instruments for use in clinical studies. The EADV TFs recommend the dermatology‐specific DLQI questionnaire for use in HS patients. The EADV TFs encourage the further development, validation and use of other HS‐specific, dermatology‐specific and generic instruments but such use should be based on the principles presented in the previous publications of the EADV TF on QoL and Patient‐Oriented Outcomes.