Hidradenitis suppurativa

Machine Learning for Early Detection of Hidradenitis Suppurativa: A Feasibility Study Using Medical Insurance Claims Data

Patients with hidradenitis suppurativa (HS) are often misdiagnosed and may wait up to 10 years to receive a diagnosis of HS. This study aimed to predict HS diagnosis prior to actual diagnosis on the basis of previous medical history using models developed with insurance claims data. Three machine learning models were compared with a model using features selected by a dermatologist (clinical baseline model). The study analyzed 5,900,000 United States individuals' insurance records over 13.5 years. The population included 13,886 patients with HS with at least 1 claim in each of the 2 years prior to their first HS diagnosis and 69,428 control patients with no HS diagnosis. The models aimed to classify HS diagnosis status on the basis of clinical features observed over 2 years. Model performance was assessed by area under the receiver operating characterisitic curve, F1-score, and precision and recall rates. The machine learning models (logistic regression, random forest, and XGBoost) showed a higher area under the receiver operating characterisitic curve than the clinical baseline model (logistic regression = 0.75, random forest = 0.79, XGBoost = 0.80, clinical = 0.71). In the clinical model and the best-performing XGBoost model, the top features associated with diagnosis were patient age at prediction and sex. The XGBoost model top features also included the use of sulfamethoxazole/trimethoprim and clindamycin phosphate and obesity.

The role of interleukin inhibitors in the treatment of hidradenitis suppurativa; a systematic review of clinical trials

Hidradenitis suppurativa (HS) is a chronic inflammatory skin disorder that presents significant treatment challenges. Recent advancements have enhanced our understanding of its pathophysiology, leading to the development of novel therapeutic strategies. This systematic review evaluates the role of interleukin (IL) inhibitors as emerging treatment options for HS. A systematic search was conducted in PubMed/Medline, Scopus, and Web of Science databases for studies published up to September 2nd, 2024, with inclusion limited to clinical trials available in English. The National Institute of Health (NIH) Quality Assessment Tool for clinical trials and before-after studies with no control group was used to assess the methodological quality of the included studies. Out of 1289 studies, 20 met our inclusion criteria involving 3957 patients. Moreover, four ongoing trials were retrieved from ClinicalTrials.gov. Secukinumab showed sustained hidradenitis Suppurativa Clinical Response (HiSCR) improvements, particularly in biologic-naïve patients with common adverse events (AEs). Bimekizumab was effective with biweekly dosing, while the four-week regimen had inconsistent results, with rare reports of AEs. Brodalumab and bermekimab provided rapid and sustained HiSCR responses with lesion reductions, which were well tolerated. Guselkumab and ustekinumab showed promising but statistically nonsignificant improvements with mild AEs. Risankizumab did not significantly improve HiSCR rates but showed Dermatology Life Quality Index (DLQI) benefits. Anakinra offered moderate efficacy with prolonged exacerbation-free periods but led to some treatment discontinuations. Spesolimab reduced inflammatory lesions and draining tunnels while maintaining a favorable safety profile. IL inhibitors, especially IL-17 inhibitors, have demonstrated efficacy in treating moderate-to-severe HS, while IL-23 inhibitors have shown inconsistent results. Despite their generally favorable safety profiles, further research is needed to optimize treatment strategies and assess long-term outcomes.

The Role of Sex in Body Composition Differences in Hidradenitis Suppurativa: Insights from Bioelectrical Impedance Analysis

Background: Hidradenitis suppurativa (HS) is a rare, debilitating, chronic inflammatory skin disease. This study aimed to investigate differences in body composition between patients with hidradenitis suppurativa (HS) and healthy controls, with a particular focus on sex-specific disparities, while also exploring secondary associations with muscle health and quality of life. Methods: Body composition was measured using a bioanalyzer and compared between HS individuals (n = 53) and controls (n = 50). Results: The mean BMI was significantly higher in the HS group than in the controls (median 29.6 vs. median 22.1; p < 0.001, effect size -0.581). The patients with HS had a significantly higher fat mass (mean 26.2 ± 22.7 vs. 16.3 ± 6.0; p < 0.001, effect size -0.400), level of visceral fat (median 9 vs. 2; p < 0.001, effect size -0.473), percentage of total body water (mean 45.9 ± 12.3 vs. 31.9 ± 14.3; p < 0.001, effect size -0.508), skeletal muscle index (median 8.9 vs. 7.3; p < 0.001, effect size -0.445), and bone mass (median 3.2 vs. 2.5; p < 0.001, effect size -0.421); at the same time, they had a significantly lower predicted muscle mass (median 19.8 vs. 47.3; p < 0.001, effect size -0.740) and percentage of skeletal muscle mass (mean 38.2 ± 7.8 vs. 42.3 ± 5.5; p = 0.008, effect size -0.263) in comparison to the controls. The HS group was also characterized by a higher metabolic age (median 65 vs. 21 years; p < 0.001, effect size -0.760) and basal metabolic rate (median 1927 vs. 1489 kcal; p < 0.001, effect size -0.444). Conclusions: Patients with HS exhibit a distinctive pattern in body composition parameters when compared to healthy controls, which may hold significant potential for enhancing diagnostic accuracy and monitoring disease progression. This study highlighted sex-specific differences in body composition, emphasizing the need to consider biological sex in the pathophysiology and clinical evaluation of HS. Further research is needed to explore the clinical utility of body composition analysis in disease progression, therapeutic response, and personalized management.

Exploring global natural product databases for NLRP3 inhibition: Unveiling novel combinatorial therapeutic strategy for hidradenitis suppurativa

BACKGROUND

Hidradenitis suppurativa (HS) is a chronic inflammatory skin condition of the terminal hair follicle, which can present in sporadic, familial, or syndromic forms. The exact pathogenesis of HS remains elusive, posing a challenge for the development of effective treatments. Among the various immunological mechanisms, the NLRP3 inflammasome is thought to contribute to the pathogenesis of HS, releasing cytokines such as IL-1β and IL-18 which initiates and exacerbates inflammation. Consequently, targeting NLRP3 offers a potential strategy for mitigating inflammation in HS-affected skin.

METHODS

In this study we used the docking, molecular dynamics simulation and binding free energy approaches to identify the potent inhibitor of NLRP3 by screening the African phytocompounds and traditional Chinese medicine databases.

RESULTS

Our virtual drug screening analysis identified two lead compounds from each database, characterized by high docking scores such as SA-21676268 (-8.135 kcal/mol), SA-167673 (-10.251 kcal/mol), EA-45360194 (-10.376 kcal/mol), EA-46881231 (-10.011 kcal/mol), NEA-44258150 (-9.856 kcal/mol), NEA-135926572 (-7.662 kcal/mol), NA-163089376 (-9.237 kcal/mol), NA-440735 (-8.826 kcal/mol), TCM-392442 (-10.438 kcal/mol), and TCM-10043097 (-9.046 kcal/mol) which highlighted the strong binding affinity as compared to the control NP3-146 drug (-5.09 kcal/mol). Moreover, the values of dissociation constant further validated the strong binding affinity between the identified lead compounds and NLRP3. The dynamic stability and strong bonding energies of the lead compounds-NLRP3 complexes were confirmed by the molecular dynamic simulation and binding free energy calculation. The analysis of ADMET properties for all compounds indicated high intestinal absorption, water solubility, absence of hepatotoxicity, and skin sensitivity.

CONCLUSION

In conclusion, our molecular simulations and binding free energy calculations confirmed the strong affinity of these lead compounds for NLRP3 as compared to the control drug, highlighting their potential as part of a combinatorial therapeutic strategy for HS to effectively reduce disease-related inflammation.

Managing Hidradenitis Suppurativa with Biologics and Small Molecule Inhibitors

"Hidradenitis suppurativa (HS) is a chronic inflammatory skin disease with a significant quality-of-life impact. In addition to the 2 drugs approved by the Food and Drug Administration for HS, adalimumab and secukinumab, several other biologic and small molecule inhibitors are used off-label or are in clinical trials. A systematic and evidence-based approach using these and other therapies-considering patient comorbidities, response to therapy, dose adjustment, and frequent troubleshooting-is required. In this article, we review the latest evidence supporting anti-inflammatory biologic and small molecule therapies for HS and provide a practical, algorithmic approach to management incorporating experience and expert opinion."

Different Phenotypes of Hidradenitis Suppurativa

Hidradenitis suppurativa (HS) is a chronic inflammatory disorder with a heterogeneous phenotype. HS is a recurrent, fluctuating disease with various natural histories. Its phenotypes have been associated with responses to therapy; however, more studies about treatment response are needed, as is evaluation of biomarkers, before conclusions can be reached. This article provides a scoping review of HS phenotypes reported in the literature, with the hope that the results may offer insights for a more individualized approach to treatment.

The preclinical discovery and development of secukinumab for the treatment of moderate-to-severe hidradenitis suppurativa

INTRODUCTION

Hidradenitis suppurativa (HS) is a chronic skin condition with a significant impact on patient quality of life, highlighting the need for innovative therapeutic approaches. HS is characterized by its chronicity; it presents in the form of painful nodules, abscesses, and sinus tracts or fistulas, typically localized in intertriginous areas, emerging in early adulthood and in predominantly the female population.

AREAS COVERED

In this review, the authors discuss the preclinical discovery and development of secukinumab for HS, highlighting target identification, validation, and compound selection. Methodologies such as high-content screening, chemoinformatics, and animal models that validate the IL-17 pathway's role in HS are explored. The transition from preclinical to clinical development, including pharmacokinetics (PK), pharmacodynamics (PD), and ADME-Tox studies, is elaborated. The literature search was conducted using PubMed, Web of Science, Scopus, UpToDate, Cochrane Library, Embase, and Google Scholar, covering relevant studies published up to December 2024.

EXPERT OPINION

The integration of secukinumab into HS treatment highlights the critical role of targeting the IL-17A pathway. Although efficacious and safe in trials, understanding secukinumab's long-term effects and optimal treatment placement remains challenging. Future research should prioritize the development of tailored therapeutic strategies that align with individual disease phenotypes and immune profiles to enhance treatment outcomes in HS management.

Addressing the Dressings: Wound Care in Hidradenitis Suppurativa

Hidradenitis suppurativa (HS) wounds are complex and have unique characteristics that complicate dressing selection. Proper wound care assists with wound healing and contributes to improved quality of life. Ideal dressings are comfortable while maintaining a wound-healing environment. Antimicrobial dressings should target dysbiosis and biofilms. Absorptive dressings are needed for control of exudate. Pain control is best achieved with nonadhesive dressings and contact layers. Agents targeting anaerobic bacteria are effective at odor reduction. Surgery may be indicated for management of refractory wounds. Overall, there is a need for increased research and education on both routine and postsurgical wound care in HS.

Hidradenitis Suppurativa Epidemiology

Hidradenitis suppurativa (HS) is a chronic inflammatory skin condition characterized by painful skin abscesses, fistulizing sinus tracts, and scarring. Despite its devastating negative effects on patients' health, quality of life, performance, and mental health, HS epidemiology is not well understood. This study aims to better characterize the epidemiology of HS, including incidence, prevalence, various demographic distributions, and risk factors. This can further the understanding of HS disease development and improve recognition, diagnosis, and treatment.

Systematic review and meta-analysis of peripheral blood inflammatory markers in hidradenitis Suppurativa

Despite the systemic inflammatory implications of hidradenitis suppurativa (HS), the relationship between systemic inflammatory markers and HS has not been definitively established in the existing literature. This review aimed to evaluate the relationship of peripheral blood inflammatory markers such as erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), monocyte-to-lymphocyte ratio (MLR), pan-immune-inflammation value (PIV) and systemic immune-inflammation index (SII) with the presence and severity of HS. A comprehensive search of the PubMed, Embase and Cochrane databases was conducted. Studies with data on these peripheral blood inflammatory markers in HS patients were included. A meta-analysis was performed using standardized mean differences to evaluate the association between these inflammatory markers and HS. Our study included 23 research articles that included 2623 cases and 22 015 controls. The results demonstrated that (1) CRP, ESR, NLR, and SII levels were significantly higher in HS patients than controls, and (2) CRP, ESR, PIV, and SII positively correlated with HS severity between Hurley stages I and II and II and III. NLR and PLR also correlated with severity between stages II and III. CRP, ESR, NLR and SII are significantly associated with the presence of HS, while CRP, ESR, SII, and PIV are important indicators of HS severity. NLR and PLR become particularly significant in groups with severe HS. Our results underscore the systemic inflammatory involvement in HS and suggest that these inflammatory markers could be valuable in clinical practice for screening and monitoring the progression of HS.

Plant-Based Foods for Chronic Skin Diseases: A Focus on the Mediterranean Diet

PURPOSE OF REVIEW

In this narrative review, we provide an overview of how adherence to a Mediterranean dietary pattern can complement traditional treatment strategies for psoriasis, acne, and hidradenitis suppurativa. We emphasize the importance of an integrated approach, with dietary interventions as a key component of holistic patient care.

RECENT FINDINGS

Psoriasis, acne, and hidradenitis suppurativa are immune-mediated chronic diseases marked by systemic inflammation, with genetic and environmental factors influencing their onset. The Mediterranean diet, rich in plant-based foods with antioxidant and anti-inflammatory properties-such as whole-grain cereals, extra-virgin olive oil, vegetables, legumes, fruits, and nuts-has been shown to reduce the clinical severity of these conditions. It also supports weight control and positively impacts metabolic and cardiovascular risk factors, which are closely linked to these diseases. Dietary education, particularly about the Mediterranean diet, plays a crucial role in the management of these skin diseases and serves as an important non-pharmacological treatment option that can influence patient prognosis. This review offers specific nutrition recommendations for prescribing the Mediterranean diet to patients with chronic inflammatory skin diseases.

Inflammatory proteins and hidradenitis suppurativa: Insights from genetic correlation and Mendelian randomization

Previous research has highlighted a significant association between inflammatory proteins and the development and progression of hidradenitis suppurativa (HS). Nevertheless, the potential causative link between these factors remains to be definitively established. To investigate the genetic correlation between inflammatory proteins and HS, linkage disequilibrium score regression (LDSC) was employed. Mendelian randomization (MR) analysis, incorporating inverse variance weighted, MR-Egger, and weighted median methodologies, was utilized to evaluate the possible causal relationship between circulating inflammatory proteins (CIPs) and HS. Additionally, reverse MR analysis was carried out to explore reverse causality. The data set for 91 CIPs was derived from a genome-wide protein quantitative trait loci study, while HS-related data were acquired from the FinnGen study. Moreover, the stability of the causal relationships was assessed via sensitivity analyses, encompassing tests for pleiotropy, heterogeneity, and leave-one-out analysis. The LDSC analysis suggested the existence of genetic correlations between the levels of Fibroblast growth factor 21 (FGF-21), stem cell factor, and HS. The MR analysis identified a suggestive association of T-cell surface glycoprotein CD5 and C-X-C motif chemokine 11 with an elevated risk of HS. Conversely, C-C motif chemokine 4, Protein S100-A12, Interleukin-10 receptor subunit beta, and Programmed cell death 1 ligand 1 were associated with a diminished risk of HS. Moreover, HS was demonstrated to increase the levels of four CIPs: Interleukin-20, Leukemia inhibitory factor (LIF), LIF receptor, and Thymic stromal lymphopoietin. The findings of this investigation offer suggestive evidence for possible genetic correlations and causal links between various genetically predicted inflammatory proteins and HS. There exists a pressing requirement for additional studies to elucidate the fundamental processes driving these associations.

Hidradenitis Suppurativa from a Multi-Omic Scope

Hidradenitis suppurativa (HS) is recognized as a systemic immune-mediated disease (IMID), sharing genetic and environmental risk factors with other IMIDs such as inflammatory bowel disease and psoriasis. Over time, correlating clinical findings with genetic, proteomic, and metabolomic results has been challenging due to diverse sampling methods, analysis techniques, and the use of variable clinical phenotype descriptions across studies. This review aims to summarize the results from various omics fields to explore the etiopathology of HS. Genetic studies highlight defects in Notch and γ-secretase signaling and inflammasome function. Syndromic HS involves specific mutations in autoinflammatory syndromes such as pyogenic sterile arthritis, pyoderma gangrenosum, and acne (PAPA) and pyoderma gangrenosum, acne, and HS (PASH). Proteomic analyses reveal key inflammatory pathways indicating activation of both innate and adaptive immunity. Additionally, microbiome studies show an increased presence of anaerobes like Prevotella in HS lesions and a decreased presence of commensals such as Staphylococcus epidermidis. Gut microbiota dysbiosis, particularly involving Ruminococcus gnavus and Clostridium ramosum, is associated with HS. Moreover, metabolomic profiling indicates dysregulated tryptophan catabolism and lipid metabolism, with increased 5-lipoxygenase-derived metabolites and odd-chain fatty acids suggesting bacterial involvement. In summary, despite advances, robust associations between genetics, proteomics, microbiome, and metabolomics in HS are still lacking. Integrating these datasets could identify new clinical phenotypes, genetic predispositions, microbial signatures, and therapeutic targets, enhancing personalized treatment strategies and biomarker discovery for HS classification, prognosis, and treatment response.

Hepatocyte Growth Factor Has Unique Functions in Keratinocytes that Differ from those of IL-17A and TNF and May Contribute to Inflammatory Pathways in Hidradenitis Suppurativa

Hidradenitis suppurativa (HS) is a chronic inflammatory disease that is difficult to control, and its mechanism remains unclear. Hepatocyte GF (HGF) has been reported to be significantly upregulated in the serum and skin of patients with HS, especially in the lesions with tunnels. In this study, we examined the transcriptome of HGF-treated keratinocytes and compared it with genetic profiling of HS lesions. HGF was highly expressed in HS skin, especially in the deep dermis, compared with that in healthy controls, and its source was mainly fibroblasts. HGF upregulated more genes in keratinocytes than IL-17A or TNF-a, and these genes included multiple epithelial-mesenchymal transition-related genes. Differentially expressed genes in HGF-stimulated keratinocytes were involved in activation of epithelial-mesenchymal transition-related pathways. These HGF-induced genes were significantly upregulated in HS lesions compared with those in healthy skin and nonlesions and were more strongly associated with HS tunnels. In summary, HGF was highly expressed in HS and induced epithelial-mesenchymal transition-related genes in keratinocytes; HGF-induced genes were highly associated with gene profiling of HS with tunnels, suggesting that HGF may be involved in HS tunnel formation through epithelial-mesenchymal transition.

Australasian hidradenitis suppurativa management guidelines

Hidradenitis Suppurativa is a burdensome inflammatory skin disease with significant quality of life impact. These management guidelines were developed to direct appropriate clinical management in the Australasian context. A systematic review was used for the basis of the consensus guidelines. Thirteen clinical experts were involved in a modified Delphi consensus process to develop the guidelines and treatment algorithms. Overall management strategies include appropriate severity assessment of disease and comorbidities, multimodal therapy with systemic and local treatments, and evidence-based progression along the therapeutic ladder in the event of inadequate response. Sequential monotherapy with antibiotics and/or single agent therapy is discouraged and aggressive treatment of moderate to severe disease to capture the window of opportunity is highly emphasised. Specific considerations in the setting of disease comorbidities, pregnancy and breastfeeding are also addressed. Overall, the complex nature of HS requires a complex and multimodal therapeutic response with medical, physical and surgical therapies to achieve best patient outcomes.

Human papillomavirus infection is associated with increased risk of new-onset hidradenitis suppurativa: A population-based cohort study

BACKGROUND

The exact cause of hidradenitis suppurativa (HS) remains unclear, although emerging research suggests a link between infectious agents and inflammatory skin diseases. The association between human papillomavirus (HPV) infection and HS development, however, has not been studied.

OBJECTIVE

The objective of this study was to evaluate the risk of incident HS in patients with HPV infection.

METHODS

Using the TriNetX research network, we conducted a retrospective cohort study of patients diagnosed with HPV and matched controls. Propensity score matching adjusted for variables like age, sex (male/female), race, body mass index, comorbidities, and lifestyle factors. The primary outcome was new-onset HS, analyzed across demographic and clinical factors. Hazard ratios with 95% confidence intervals were calculated to assess the risk.

RESULTS

After matching, both the HPV and control cohorts included 582,007 patients. HPV-infected individuals had a significantly higher risk of developing HS (hazard ratio: 1.356, 95% confidence interva: 1.290-1.427). This increased risk was consistent across various demographic and clinical groups. Sensitivity analyses confirmed the robustness of these findings.

LIMITATIONS

Retrospective cohort design.

CONCLUSIONS

HPV infection is linked to a higher risk of HS, suggesting a potential association. Further research is required to validate these results and assess their impact in different populations and clinical settings, as well as also elucidate the potential impact of other infections involved in the pathogenesis of HS.

Hidradenitis suppurativa, from basic science to surgery and a new era of tailored targeted therapy: An expert opinion paper

Hidradenitis suppurativa (HS) is a chronic inflammatory disease characterised by an aberrant activation of innate immunity and increased production of pro-inflammatory mediators such as interleukin 17 (IL-17). IL-17 has been shown to play a key role in the pathogenesis of HS and evidence highlights the potential of IL-17-targeted therapies. The fully human IgG/κ monoclonal antibody secukinumab, which specifically targets IL-17A and inhibits interaction with its receptor, has recently been approved for the treatment of moderate-to-severe HS. Secukinumab offers patients an efficacious and well-tolerated treatment option in terms of sustained response by rapidly improving signs and symptoms, and preventing disease progression in the absence of loss of response. Being a challenging disease, HS is associated with a delay to diagnosis of 3-10 years and, consequently, late implementation of appropriate treatment, leading to disease progression. Misdiagnosis due to flawed understanding and lack of awareness among medical providers and patients is considered an important factor contributing to the delayed diagnosis. Thus, serious efforts must be made on a large scale to urgently reduce the delay in HS diagnosis and reduce the disease burden in patients, including raising awareness, implementation of education programmes at medical and specialisation schools, as well as continuous education of healthcare providers at different levels for the early detection of HS and initiation of appropriate treatment. Here, we present the main critical unmet needs in the diagnosis and treatment of patients affected by HS, address how disease awareness and comprehensive multidisciplinary management (offering both medical and surgical care) can benefit patients, and suggest therapeutic options, based on clinical characterisation and early identification and intervention (window of opportunity), to be adopted for a timely and better management of disease progression and to fill current gaps.

Increased risk of incident alopecia areata among patients with hidradenitis suppurativa: A multicenter cohort study in the United States

BACKGROUND

Hidradenitis suppurativa (HS) and alopecia areata (AA) share similar inflammatory pathway and pro-inflammatory cytokines. However, the association between HS and AA was unclear. We aimed to evaluate the risk of incident AA among patients with HS.

MATERIAL AND METHODS

We performed a multicenter cohort study by using the US Collaborative Network in the TriNetX Research Network. Patients with HS diagnosis were recruited and 1:1 propensity score matching was performed to identify the non-HS control group. Hazard ratio (HR) of AA in different sensitivity models were calculated within the follow-up periods.

RESULTS

Comparing with non-HS controls, the risk of incident AA in HS patients was 1.79-fold higher (95% confidence interval (CI) 1.31-2.44) within 15-year follow up. Similar trends were observed in 3-year and 8-year follow up. For female HS patients, the risk of incident AA was 1.75-fold higher than non-HS female (95% CI 1.23-2.48). However, the trend was not observed in male HS patients (HR 1.52; 95% CI 0.79-2.94).

CONCLUSIONS

Patients with HS were associated with increased risk of incident AA. Clinicians should be aware of the observed association and the actual immunological interplay between the two diseases should be clarified in future lab-based studies.

Crosstalk Between the Skin Environment and Microbial Community in Immune-Related Skin Diseases

The skin surface hosts diverse skin microbiota, including bacteria, fungi, and viruses. Intricate interactions between the skin microenvironment and microbial community are crucial for maintaining cutaneous homeostasis. This review explores the bidirectional relationship between the skin ecosystem and its microbiota. The skin microenvironment is shaped by a combination of intrinsic factors, dominated by sweat glands and pilosebaceous units, and external factors, such as UV radiation and personal care products, which create distinct niches that influence microbial colonization patterns across different skin regions. The skin microbiome, in turn, modulates the physical, chemical, immunological, and microbial barriers of the skin. We also discuss the alterations in this crosstalk in various immune-related skin conditions such as atopic dermatitis, psoriasis, rosacea, hidradenitis suppurativa, skin cancer, and aging. Understanding these interactions is vital for developing targeted microbiome-based therapies for various skin disorders. Further researches are needed to deepen insights into the microbial roles and their therapeutic potentials in skin health and disease.

Beyond the skin: endocrine, psychological and nutritional aspects in women with hidradenitis suppurativa

Hidradenitis suppurativa (HS), also known as acne inversa, is a chronic inflammatory skin disorder that primarily affects body folds and the genital area, with a higher prevalence in women across Europe. The pathogenesis of HS involves a complex interplay of intrinsic and extrinsic factors, including genetics, immunity, hormones, and environmental influences. HS is frequently associated with a variety of comorbidities, such as metabolic, endocrine, and gastrointestinal conditions, as well as mental health disorders. Although the symptoms of HS are generally similar in both men and women, female patients may experience exacerbations of HS due to hormonal fluctuations during menstruation, pregnancy, breastfeeding, and menopause. These hormonal changes require special consideration by clinicians when managing HS in women. Due to its chronic nature and frequent flare-ups, HS significantly impacts patients' quality of life, affecting social interactions, emotional well-being, and psychological health. Women with HS may also experience sexual dysfunction, which is further exacerbated by emotional burdens such as shame, loss of femininity, and diminished intimacy. This review highlights key aspects of HS, extending beyond its skin manifestations to address endocrine, psychological, and nutritional aspects in the female population. It also underscores the importance of multidisciplinary collaboration in providing comprehensive care for women with this debilitating condition. Given the limited and largely off-label treatment options, a holistic approach is essential to ensure an appropriate management.

Improvements in moderate-to-severe hidradenitis suppurativa with upadacitinib: Results from a phase 2, randomized, placebo-controlled study

BACKGROUND

Hidradenitis suppurativa is a disabling inflammatory skin disease.

OBJECTIVE

To investigate the efficacy and safety of upadacitinib, a selective Janus kinase inhibitor.

METHODS

In this phase 2, randomized, placebo-controlled, double-blind clinical trial (NCT04430855), adults with moderate-to-severe hidradenitis suppurativa were randomized 2:1 to once-daily upadacitinib 30 mg or placebo. At 12 weeks, placebo patients switched to blinded upadacitinib 15 mg, and patients receiving upadacitinib 30 mg continued assigned treatment through week 48. The primary endpoint was ≥50% reduction in total abscess and inflammatory nodule count with no increase in abscess or draining fistula count relative to baseline (Hidradenitis Suppurativa Clinical Response [HiSCR50]) at week 12.

RESULTS

Forty-seven patients received upadacitinib; 21 patients received placebo. At week 12, a significantly greater proportion of patients receiving upadacitinib achieved HiSCR50 vs a prespecified historical placebo rate (38.3% vs 25.0%; 1-sided P = .018). Comparison with the in-trial placebo group showed an adjusted difference of 14.7% (nominal P = .087). HiSCR50 achievement with upadacitinib was consistent across baseline Hurley stage and prior tumor necrosis factor inhibitor exposure and maintained through week 40. Upadacitinib's safety profile was consistent with previous reports on dermatologic conditions.

LIMITATIONS

Sample size was small.

CONCLUSION

Findings support further investigation of upadacitinib for moderate-to-severe hidradenitis suppurativa.

Large-scale analysis highlights obesity as a risk factor for chronic, non-communicable inflammatory diseases

Background

Overweight and obesity are a global pandemic, contributing to death and disability-adjusted life-years. Obesity is a major factor in the onset of chronic inflammatory diseases (CIDs). Yet, several knowledge gaps remain: For several CIDs, inconsistent results have been reported, relating to their obesity-imposed risk, data on most rare CIDs remain unavailable, sex differences and racial disparities remain mostly unaddressed.

Methods

A large-scale cohort study compared the risk of developing 46 CIDs in individuals with overweight/obesity (n=3,101,824) to an equal number of non-overweight/obese individuals. Propensity score matching optimized between-group comparability, and sensitivity analyses assessed study robustness.

Results

The risk of developing any CID was 28.48% in overweight/obese individuals versus 17.55% in non-overweight/obese controls, with a hazard ratio (95%-confidence interval) of 1.52 (1.509-1.521, p<0.0001). This risk was consistent across all sensitivity, sex-, and race-stratified analyses. Overweight and obesity were associated with an increased risk for 24 of 46 CIDs in the primary analysis and all sensitivity analyses. For 12 diseases, increased risks were confirmed to one of the two sensitivity analyses, while for 10 diseases, results were discordant. No increased risk was observed for one disease. In sex-stratified analysis, overweight and obesity posed a more pronounced risk for four CIDs in female individuals. In race-stratified analysis, overweight and obesity were linked to a higher risk for seven CIDs in White individuals and to one CID in "Black or African American" individuals.

Conclusion

Overweight and obesity increase the risk for the majority of CIDs in a sex- and race-specific manner.

Hidradenitis suppurativa

Hidradenitis suppurativa is a chronic inflammatory disease characterised by painful, deep-seated nodules, abscesses, and draining tunnels in the skin of axillary, inguinal, genitoanal, or inframammary areas. In recent years, the body of knowledge in hidradenitis suppurativa has advanced greatly. This disorder typically starts in the second or third decade of life. The average worldwide prevalence is 1% but varies geographically. Hidradenitis suppurativa has a profound negative effect on patients' quality of life and on the gross value added to society. Comorbidities (eg, metabolic syndrome, inflammatory arthritis, and inflammatory bowel disease) frequently accompany skin alterations, because of systemic inflammation. Pathogenesis of hidradenitis suppurativa is complex and includes innate immune mechanisms (eg, macrophages, neutrophils, IL-1β, tumour necrosis factor [TNF], and granulocyte colony-stimulating factor), T-cell mechanisms (eg, IL-17 and IFN-γ), and B-cell mechanisms (eg, associated with dermal tertiary lymphatic structures and autoantibodies). Chronic inflammation leads to irreversible skin damage with tunnel formation and morbid scarring. Current treatment includes drug therapy (for the initial, purely inflammatory phase), combined drug and surgical therapy (for the destructive phase), or surgery alone (for the burnout phase). The first systemic therapies approved for hidradenitis suppurativa targeting TNF (adalimumab) and IL-17 (secukinumab and bimekizumab) have expanded drug therapy options for moderate-to-severe disease, which were previously mainly restricted to oral antibiotics. Moreover, there is a robust pipeline of immunomodulatory drugs in various stages of development for hidradenitis suppurativa. Aims of management should include early intervention to prevent irreversible skin damage, adequate control of symptoms including pain, and mitigation of extra-cutaneous comorbidities, all requiring early diagnosis and an interdisciplinary, holistic and personalised approach.

IRAK4 Is Overexpressed in Hidradenitis Suppurativa Skin and Correlates with Inflammatory Biomarkers

Hidradenitis suppurativa (HS) is a chronic inflammatory disease manifesting as painful dermal nodules, abscesses, and tunnels. Activation of the IL-1R/toll-like receptor pathway is strongly implicated in the pathogenesis of HS; thus, the role of a key signaling node, IRAK4, was investigated in a noninterventional study (NCT04440410) that enrolled 30 patients with HS. IRAK4 expression was evaluated in blood and lesional, perilesional, and nonlesional skin biopsies. PBMCs expressed IRAK4, with significantly higher levels in monocytes (P ≤ .0001). Ex vivo treatment of PBMCs with KT-474, a targeted degrader of IRAK4, robustly decreased IRAK4 in all immune cell types from healthy volunteers and patients with HS. Ex vivo treatment of toll-like receptor-stimulated healthy donor monocytes with KT-474 decreased IRAK4 protein levels and inhibited inflammatory cytokine production. In HS skin samples, IRAK4 protein levels were significantly higher in lesional than in nonlesional tissue (P ≤ .0001), and IRAK4-positive immune infiltrate increased with greater disease severity. Multiple inflammatory mediators were upregulated in HS lesional skin, correlating with IRAK4 overexpression. These data confirm the significance of the IL-1R/toll-like receptor pathway in the pathogenesis of HS and provide support for ongoing clinical studies evaluating KT-474 in the treatment of HS.

Implementation Science to Improve the Diagnosis and Management of Hidradenitis Suppurativa: HELyx Study Design Overview

INTRODUCTION

Hidradenitis suppurativa (HS) is a chronic, inflammatory skin disease associated with a high disease burden and substantial impact on patients' quality of life. Limited therapeutic options are available, with an unmet medical need for earlier diagnosis and treatment and more effective treatment options. Low awareness of HS amongst healthcare professionals (HCPs) leads to delayed diagnosis and a prolonged patient journey to HS-specific treatment. This article aims to describe the design of HELyx, an implementation science study in Germany, which aims to evaluate the effectiveness of an implementation strategy to improve screening and diagnosis of HS among HCPs (dermatologists and non-dermatologists) and timely referral to HS-treating dermatologists.

METHODS

HELyx is a hybrid, effectiveness-implementation science study with a pre-post design involving HCPs and is guided by the Consolidated Framework for Implementation Research. HELyx is being conducted in Germany over four consecutive phases (context analysis, pre-implementation, implementation, and post-implementation) in a sequential manner. A similar implementation science study is also being conducted in the United Arab Emirates (UAE) and Spain. HELyx aims to identify key unmet medical needs in the HS patient journey, to develop and implement a tailored medical education program, and to measure the effectiveness of the implementation.

PLANNED OUTCOMES

The primary endpoint is the change in the proportion of HCPs who used a diagnostic screening tool to identify patients with suspected HS during the 24 weeks of the post-implementation phase (assessed at Week 24) compared to the 24 weeks before implementation (assessed at baseline). Secondary endpoints include assessment of the use of HS disease severity assessment and patient-reported outcome tools and HCP referral behaviours.

What Do We Know About Bacterial Infections in Hidradenitis Suppurativa?-A Narrative Review

Background/Objectives: Hidradenitis suppurativa is an inflammatory skin condition of the pilosebaceous unit of a chronic, painful, and progressive nature. It affects intertriginous parts of the body, including the axillae, groin, submammary region, and anogenital region. The risk of infection in HS patients is not well understood. Thus, presenting the most recent findings in the study of bacterial infections in relation to hidradenitis suppurativa was the objective of this review. Methods: The presented article is a narrative review. The PubMed and Scopus databases were searched for articles applicable to this review. All types of study design were included in this review. Results: Among reported infections in patients with HS, Fournier's gangrene, osteomyelitis, Clostridium difficile infection, and biofilm were significant. Attention should also be paid to post-procedural infections. Conclusions: A wide range of bacterial infections, from localized purulent infections to serious systemic consequences, can affect patients with HS. Comorbid diseases like diabetes mellitus and obesity change the cutaneous microbiota and produce a pro-inflammatory systemic milieu, which makes the disease more severe and makes HS patients more susceptible to infections. Additionally, those with untreated or unmanaged HS are more likely to experience infectious complications.

A comprehensive systemic review and meta-analysis of the association between lipid profile and hidradenitis suppurativa

BACKGROUND

While several studies have suggested a connection between Metabolic Syndrome (MetS) and Hidradenitis Suppurativa (HS), a definitive analysis confirming the association between lipid abnormalities and HS based on actual lipid values is lacking. Previous research, using odds ratios from ICD codes, indicates links between elevated triglycerides and low high-density lipoprotein levels with HS. However, these findings may not fully represent real-life situations, as no comprehensive analysis using actual lipid measurements has been performed.

OBJECTIVES

To examine the relationship between lipid profile values-total cholesterol, triglycerides (TG), low-density lipoprotein (LDL), and high-density lipoprotein (HDL)-and HS.

METHODS

A comprehensive search of PubMed, Cochrane Library, and Embase was conducted to identify studies reporting lipid profiles in HS patients. A meta-analysis using standardized mean differences (SMDs) was performed to assess the association between lipid abnormalities and HS.

RESULTS

The meta-analysis found that HS patients had significantly higher TG levels (SMD = 0.28, 95% CI: 0.09-0.47, P = 0.004) and lower HDL levels (95% CI: -0.53 to -0.16, P < 0.001) compared to healthy controls. No significant differences were observed in total cholesterol (SMD = 0.01, 95% CI: -0.19-0.21, P = 0.93) and LDL levels (SMD = 0.04, 95% CI: -0.10-0.17, P = 0.61). These results corroborate earlier studies linking HS with dyslipidemia, particularly hypertriglyceridemia and hypo-HDL cholesterolemia, with the added strength of using actual lipid values.

CONCLUSIONS

This study confirms the association between hypertriglyceridemia and low HDL cholesterol in HS patients, highlighting the broader systemic association of the condition. Dermatologists should monitor lipid profiles in HS patients to mitigate potential cardiovascular risks through early detection and management.

Factors associated with therapeutic response to adalimumab in hidradenitis suppurativa: evidence from the Belgian patients of the European Registry for Hidradenitis Suppurativa (ERHS-Be)

Hidradenitis suppurativa is an inflammatory skin disease for which adalimumab is an effective treatment in just over half of cases. Few factors associated with therapeutic response, and therefore potentially predictive of response, are known to date. This real-life study retrospectively explores the existence of such factors in a Belgian cohort of 82 patients, using several response scores: the Hidradenitis Suppurativa Clinical Response (HiSCR), the International Hidradenitis Suppurativa Severity Scoring System-55 (iHS4-55), and the dynamic metascore (a combination of the Hurley score, the 2007 version of the Sartorius score, the iHS4 and the HiSCR). Among the factors associated with a good therapeutic response, we find, for example, the "Frictional furunculoid" and "Conglobata" phenotypes, in contrast to the "Scarring folliculitis" phenotype, which is associated with a poorer response to treatment. Other factors associated with a good response to treatment were observed, such as the patient's description of longer flares, or, among others, the presence of inflammatory bowel disease. Subject to our sample size, the window of opportunity for adalimumab, whereby the treatment would be more effective if administered earlier, was not found in this study.

Exploring Health Literacy among Adults with Hidradenitis Suppurativa

INTRODUCTION

Health literacy plays an important role in the management of chronic and debilitating skin diseases like hidradenitis suppurativa (HS). Adequate health literacy empowers patients to understand their disease, manage it effectively, and make informed decisions about their health. Exploring the interplay between health literacy and HS is essential to improve healthcare outcomes in this population. This study aimed to assess the prevalence of limited health literacy among HS patients and its associated factors which has never been studied before.

METHODS

In this epidemiological cross-sectional study, data were collected via a population-wide survey within the Lifelines Cohort Study in the Netherlands. Health literacy of participants with HS was compared to non-HS controls. The health literacy was measured using six validated questions covering functional, communicative, and critical health literacy. Associations between the characteristics of the HS group and limited health literacy were examined.

RESULTS

Out of 56,084 adult respondents, 1,156 participants with HS were identified. The prevalence of limited functional health literacy was 24.5% in the non-HS group and 26.4% in the HS group. Our findings indicate that limited health literacy among HS patients is associated with higher body mass index (BMI) (26.9 vs. 25.8) (OR: 0.969, 95% CI: 0.941-0.998), lower education level (34.5% vs. 19.9%) (OR: 0.495, 95% CI: 0.350-0.701), lower socioeconomic status (-0.68 vs. -0.58) (OR: 1.194, 95% CI: 1.029-1.386), and more severe disease stage according to the Hurley stage (33.0% vs. 25.8%) (OR: 1.400, 95% CI: 1.005-1.952).

CONCLUSIONS

Our study highlights the importance of addressing health literacy in HS patients, given the high prevalence of limited health literacy among this group and associations with higher BMI and more severe disease stage. Limited health literacy may contribute to poorer health outcomes, suboptimal healthcare utilization, elevated healthcare costs, and health disparities. Targeted interventions to improve health literacy could enhance care quality and outcomes for HS patients.

INTRODUCTION

Health literacy plays an important role in the management of chronic and debilitating skin diseases like hidradenitis suppurativa (HS). Adequate health literacy empowers patients to understand their disease, manage it effectively, and make informed decisions about their health. Exploring the interplay between health literacy and HS is essential to improve healthcare outcomes in this population. This study aimed to assess the prevalence of limited health literacy among HS patients and its associated factors which has never been studied before.

METHODS

In this epidemiological cross-sectional study, data were collected via a population-wide survey within the Lifelines Cohort Study in the Netherlands. Health literacy of participants with HS was compared to non-HS controls. The health literacy was measured using six validated questions covering functional, communicative, and critical health literacy. Associations between the characteristics of the HS group and limited health literacy were examined.

RESULTS

Out of 56,084 adult respondents, 1,156 participants with HS were identified. The prevalence of limited functional health literacy was 24.5% in the non-HS group and 26.4% in the HS group. Our findings indicate that limited health literacy among HS patients is associated with higher body mass index (BMI) (26.9 vs. 25.8) (OR: 0.969, 95% CI: 0.941-0.998), lower education level (34.5% vs. 19.9%) (OR: 0.495, 95% CI: 0.350-0.701), lower socioeconomic status (-0.68 vs. -0.58) (OR: 1.194, 95% CI: 1.029-1.386), and more severe disease stage according to the Hurley stage (33.0% vs. 25.8%) (OR: 1.400, 95% CI: 1.005-1.952).

CONCLUSIONS

Our study highlights the importance of addressing health literacy in HS patients, given the high prevalence of limited health literacy among this group and associations with higher BMI and more severe disease stage. Limited health literacy may contribute to poorer health outcomes, suboptimal healthcare utilization, elevated healthcare costs, and health disparities. Targeted interventions to improve health literacy could enhance care quality and outcomes for HS patients.

Update vulval dermatology - diagnostics and therapy

The vulva is a periorificial skin area and as such represents a transitional zone with unique functional and physiological characteristics. Knowledge of its anatomy is limited among both the general population and healthcare professionals, and unrealistic expectations of normal proportions are common. Ignorance of anatomical variations can cause unnecessary anxiety. In Germany, specialists in gynecology and obstetrics most commonly treat neoplastic vulvar dermatoses, while chronic inflammatory dermatoses commonly affecting the female genitalia (such as psoriasis, atopic dermatitis, hidradenitis suppurativa, and vitiligo) are typically treated by dermatologists. Both specialties treat infectious vulvar dermatoses and sexually transmitted infections. Certain dermatoses, such as lichen sclerosus, lichen planus, and lichen simplex chronicus, tend to affect the vulva preferentially; however, terminology can be confusing. Therefore, this article provides basic information on vulvar anatomy and physiology and summarizes recommendations for the diagnosis and management of the most common vulvar dermatoses, with a special focus on chronic inflammatory dermatoses, to provide a useful guide for all involved specialists in daily practice. Interdisciplinary collaboration and the establishment of dedicated consultation hours may help to improve the clinical care of vulvar dermatoses.

Interleukin-17 Inhibitors in the Treatment of Hidradenitis Suppurativa

Hidradenitis suppurativa (HS) is a chronic, debilitating, inflammatory dermatosis that significantly impacts patients' quality of life, primarily manifesting as inflammatory nodules, abscesses, and tunnels. The pathogenesis of HS is not fully understood and appears to be multifactorial, involving genetic, immunological, and endocrinological factors, as well as dysbiosis of skin microbiota. Increasing evidence highlights the role of the interleukin (IL)-17 pathway in the inflammatory process and pathogenesis of HS. Consequently, IL-17 inhibitors have emerged as a promising alternative to current therapies. Recently, secukinumab received approval from both the US Food and Drug Administration (FDA) and the European Medicines Agency (EMA), while bimekizumab received approval from the EMA, for the treatment of moderate-to-severe HS in adults, with ongoing clinical trials aiming to further clarify the efficacy and safety of other drugs within this class. IL-17 inhibitors have shown effectiveness in treating moderate-to-severe HS, with safety profiles of drugs such as secukinumab and bimekizumab being comparable to their use in other dermatological conditions. On the other hand, innovative drugs such as sonelokimab and izokibep show promising results and are currently in phase III clinical trials. This review provides a comprehensive overview of current knowledge and scientific advances in HS, focusing on the IL-17 pathway's role and its inhibition as a treatment strategy, alongside examining the most recent and significant clinical studies on various IL-17 inhibitors in the treatment of HS.

The Impact of Diet on Hidradenitis Suppurativa Severity: A Cross-Sectional Case-Control Study

Background and Objectives: Hidradenitis suppurativa (HS) is a chronic inflammatory skin disease primarily affecting hair follicles, characterized by painful nodules, abscesses, and sinus tract formation. Recent evidence suggests that weight management and nutritional factors may influence HS symptoms. This cross-sectional case-control study aimed to assess the impact of body composition and nutritional factors on HS severity. Materials and Methods: We included 50 patients with HS and 50 matched controls comparable in body mass index (BMI), sex, and age. The data collected included 3-day food records, a food frequency questionnaire, 24 h physical activity records, Mediterranean Diet Adherence Screener (MEDAS) scores, body composition, and anthropometric measurements. The macronutrient and micronutrient intake, as well as dietary glycemic index (GI), were analyzed. HS severity was assessed using the Hurley staging system and the International Hidradenitis Suppurativa Severity Score System (IHS4). Results: HS patients exhibited significantly lower adherence to the Mediterranean diet and a higher dietary GI compared to controls. Their micronutrient intake was also reduced, while the consumption of junk food, dairy products, and nightshade vegetables was more frequent. The MEDAS scores and physical activity levels were negatively correlated with the IHS4 scores, while higher anthropometric measurements, dietary energy, protein, total fat, and GI showed positive correlations. The Hurley stage was negatively correlated with the MEDAS scores and positively correlated with the GI and visceral fat. In multiple regression analysis, the MEDAS score emerged as the primary variable associated with disease severity. Conclusions: These findings suggest that an increased adherence to the Mediterranean diet, intake of food with a lower GI, and maintaining an ideal body weight may positively affect HS management. Long-term studies are warranted to corroborate our findings.

Hidradenitis suppurativa: TLSs take the center stage

Hidradenitis suppurativa (HS) is a severe chronic inflammatory skin disease with limited response to therapy. In this issue of Immunity, Yu et al.1 identify skin tertiary lymphoid structures (TLSs) as primary sites for lymphocyte clonal expansion and autoantibody production, driving disease progression, and provide insight into how formation and maintenance of TLS impact therapeutic outcomes.

Skin immune-mesenchymal interplay within tertiary lymphoid structures promotes autoimmune pathogenesis in hidradenitis suppurativa

Hidradenitis suppurativa (HS) is a chronic, debilitating inflammatory skin disease characterized by keratinized epithelial tunnels that grow deeply into the dermis. Here, we examined the immune microenvironment within human HS lesions. Multi-omics profiling and multiplexed imaging identified tertiary lymphoid structures (TLSs) near HS tunnels. These TLSs were enriched with proliferative T cells, including follicular helper (Tfh), regulatory (Treg), and pathogenic T cells (IL17A+ and IFNG+), alongside extensive clonal expansion of plasma cells producing antibodies reactive to keratinocytes. HS fibroblasts express CXCL13 or CCL19 in response to immune cytokines. Using a microfluidic system to mimic TLS on a chip, we found that HS fibroblasts critically orchestrated lymphocyte aggregation via tumor necrosis factor alpha (TNF-α)-CXCL13 and TNF-α-CCL19 feedback loops with B and T cells, respectively; early TNF-α blockade suppressed aggregate initiation. Our findings provide insights into TLS formation in the skin, suggest therapeutic avenues for HS, and reveal mechanisms that may apply to other autoimmune settings, including Crohn's disease.

Corneal Manifestations in Patients with Hidradenitis Suppurativa

PURPOSE

To report two cases of bilateral blepharokeratoconjunctivitis associated with hidradenitis suppurativa (HS).

METHODS

Case report and literature review. The clinical courses of two patients with HS, including ocular presentation and medical management, are described.

RESULTS

Two female patients aged 18 and 23-years-old with severe HS presented with bilateral blepharokeratoconjunctivitis. Shared slit lamp findings included bilateral corneal neovascularization and inferior corneal thinning. Systemic immunosuppression was needed in the first case, which resulted in improvement in the patient's ophthalmic and dermatological findings.

CONCLUSION

We report two cases of bilateral blepharokeratoconjunctivitis in two patients with severe HS. To our knowledge, this association has not previously been described in the literature. Clinicians should be aware of this association given its potentially visually devastating manifestations and the need for early therapeutic interventions.

Advances in Microbiome-Based Therapeutics for Dermatological Disorders: Current Insights and Future Directions

The human skin hosts an estimated 1000 bacterial species that are essential for maintaining skin health. Extensive clinical and preclinical studies have established the significant role of the skin microbiome in dermatological disorders such as atopic dermatitis, psoriasis, diabetic foot ulcers, hidradenitis suppurativa and skin cancers. In these conditions, the skin microbiome is not only altered but, in some cases, implicated in disease pathophysiology. Microbiome-based therapies (MBTs) represent an emerging category of live biotherapeutic products with tremendous potential as a novel intervention platform for skin diseases. Beyond using established wild-type strains native to the skin, these therapies can be enhanced to express targeted therapeutic molecules, offering more tailored treatment approaches. This review explores the role of the skin microbiome in various common skin disorders, with a particular focus on the development and therapeutic potential of MBTs for treating these conditions.

Exploring racial and ethnic disparities in the hidradenitis suppurativa patient disease journey: Results from a real-world study in Europe and the USA

Hidradenitis suppurativa (HS) is an inflammatory skin disease associated with high morbidity and disability that has limited treatment options. People from racial and ethnic minority groups may experience greater disease severity and delay to diagnosis. This study assessed the impact of race/ethnicity on HS diagnosis and management in real-world clinical settings. Data were derived from the Adelphi Real World Hidradenitis Suppurativa Disease Specific Programme, a survey of dermatologists and their consulting HS patients in five European countries and the USA in 2020/2021. Dermatologists returned demographic and clinical data, and treatment goals and satisfaction for their next five to seven consulting patients. Patients completed a questionnaire on disease history and diagnosis, disease burden, and treatment satisfaction. Groups were compared with bivariate tests. In total, 312 physicians returned data on 1787 patients; 57.6% were female and 77.7% White. People from racial and ethnic minority groups were younger than White patients (32.9 ± 11.6 vs. 34.9 ± 12.4, mean ± standard deviation) and reported symptoms at a younger age (23.3 ± 10.8 vs. 26.2 ± 11.1), but their time to first consultation was longer than for White patients (2.6 ± 5.7 vs. 1.2 ± 2.5 years). People from racial and ethnic minority groups took longer to receive a correct diagnosis following first consultation (2.7 ± 5.3 vs. 1.5 ± 4.1 years) and were more likely to be misdiagnosed with boils (73.5% vs. 40.4%). People from racial and ethnic minority groups had a greater disease awareness at diagnosis and reported wanting greater support. People from racial and ethnic minority groups reported a greater impact on life, more severe pain, and a greater level of activity impairment in the Work Productivity and Activity Impairment: General Health (27.0 ± 25.2 vs. 20.0 ± 20.6). All P values were ≤0.05. These data show evidence of delayed diagnosis and higher HS symptom burden amongst people from racial and ethnic minority groups, highlighting health disparities in HS.

Subcutaneous adipose tissue: Implications in dermatological diseases and beyond

Subcutaneous adipose tissue (SAT) is the deepest component of the three-layered cutaneous integument. While mesenteric adipose tissue-based immune processes have gained recognition in the context of the metabolic syndrome, SAT has been traditionally considered primarily for energy storage, with less attention to its immune functions. SAT harbors a reservoir of immune and stromal cells that significantly impact metabolic and immunologic processes not only in the skin, but even on a systemic level. These processes include wound healing, cutaneous and systemic infections, immunometabolic, and autoimmune diseases, inflammatory skin diseases, as well as neoplastic conditions. A better understanding of SAT immune functions in different processes, could open avenues for novel therapeutic interventions. Targeting SAT may not only address SAT-specific diseases but also offer potential treatments for cutaneous or even systemic conditions. This review aims to provide a comprehensive overview on SAT's structure and functions, highlight recent advancements in understanding its role in both homeostatic and pathological conditions within and beyond the skin, and discuss the main questions for future research in the field.

Intrinsic factors in the pathogenesis of hidradenitis suppurativa: Genetics, hormones, and the microbiome

The pathogenesis of hidradenitis suppurativa is complex and multifaceted. Our understanding of disease mechanisms is in constant flux with new genetic, inflammatory, and microbiological insights upending previous paradigms and enlightening us as to the complex connections between different drivers of disease. This updated review integrates novel genetic insights from genome wide association studies, along with novel basic science data from single cell transcriptomic studies and recent interventional translational work to inform our evolving understanding of the disease. The overarching premise is that hidradenitis suppurativa is a chronic autoinflammatory disorder characterized by inflammatory dysregulation in a background of stem cell fate aberrations highly responsive to hormonal and metabolic changes. Genetic drivers are linked to both hair follicle stem cell fate and cellular response to androgen signaling. The complex mixed inflammatory circuits involve both innate and adaptive immunity, with activation of inflammatory fibroblast subsets and tertiary lymphoid organs in chronic disease. Interplay between inflammation, the cutaneous and gut microbiomes are observed both pre- and posttherapy, however causality remain unclear. Metabolic syndrome, sex hormones and insulin resistance are all interlinked, with adipose tissue being a hormonally active organ able to modulate endogenous sources of sex hormones. Future enquiry regarding factors contributing to disease progression and the identification of novel therapeutic targets will aid in more effective therapeutic strategies for management of this burdensome disease.

Equity and Outcome Events in Hidradenitis Suppurativa: Exploring Effect Modifiers Associated with Diagnostic Delay in the Real World

INTRODUCTION

Patients with hidradenitis suppurativa (HS) experience significantly delayed diagnoses of 7-10 years from symptom onset on average, but the reasons for this remain largely unknown. This study investigated drivers of diagnostic delay from the perspective of healthcare system equity.

METHODS

A literature review was performed to identify published factors associated with delayed HS diagnosis to inform data analysis. Clinical and demographic data from the Adelphi HS Disease Specific Programme (DSP)™, a real-world cross-sectional survey of dermatologists and their consulting patients in France, Germany, Italy, Spain, the UK and the USA in 2020/2021, were used to model factors influencing delay to diagnosis from onset of symptoms and first consultation.

RESULTS

Factors influencing delay to HS diagnosis in the literature with the most available evidence were misdiagnosis, delay in specialist referral and patient embarrassment. Data analysis revealed that increasing age was associated with reduced diagnostic delay after symptom onset. Patients with HS who were White or in Germany were also more likely to receive a faster diagnosis. Smokers, patients with concomitant conditions, or a family history of HS were slower to be diagnosed. When time to diagnosis following first consultation was assessed, increasing age was associated with quicker diagnosis. Moreover, patients with a family history of HS were diagnosed quicker, whereas those with high body mass index, more concomitant conditions, in employment, managed by multiple physicians or European were more delayed.

CONCLUSION

On the basis of a thorough analysis of real-world data, multiple factors that potentially influenced the timely diagnosis of HS have been identified. For the first time, this study quantifies the relative impact of these modifiers, providing valuable insights into areas that require attention for faster diagnoses and improved disease outcomes.

The role of piperacillin/tazobactam in the treatment of Hidradenitis suppurativa

Background: Hidradenitis suppurativa (HS) is a chronic inflammatory skin disease. Most patients with moderate-to-severe disease require long-term antibiotic treatment, or biologic treatments to control their disease. Despite these interventions, relapses are common. This study evaluated the effectiveness of piperacillin/tazobactam treatment in patients with Hurley stage II and III HS who experienced disease flares and did not respond to conventional antibiotic and biologic treatment. Methods: Patients with HS hospitalized at the Department of Dermatology, Sheba Medical Center between August 2021 and January 2023 were retrospectively analyzed. Results: A cohort of ten such patients were treated with piperacillin/tazobactam for 6-21 days. Eight (80%) and two (20%) patients respectively demonstrated 2- and 1-grade improvements, from their baseline HS-Physician Global Assessment score. During the follow-up period, nine patients were monitored. HS Clinical Response (HiSCR) was achieved in six (66.7%) and five (55.6%) patients at the 3- and 6-month follow-up visits, respectively. Conclusions: In conclusion, Piperacillin/tazobactam emerges as a promising therapeutic option for disease flare-up in patients with Hurley stage II and III HS who do not respond to conventional treatment. Thus, piperacillin/tazobactam should be considered as crisis therapy for this patient subset.

Hidradenitis suppurativa pathogenesis: Extrinsic factors

While genetic predisposition and immune dysregulation are recognized as key contributors to the development of hidradenitis suppurativa, accumulating research points to the influence of extrinsic factors in the pathogenesis of this condition. This review explores the roles of mechanical stress, altered skin and gut microbiome, tobacco smoking, diet, and paradoxical drug reactions as drivers of hidradenitis suppurativa onset and progression. A holistic management approach addressing these factors may be encouraged to improve disease outcomes. Further research is needed to fully determine the causal role of these extrinsic factors and their impact on treatment strategies.

Evaluating the Internet as a Source of Information for Patients With Hidradenitis Suppurativa: A Review of Websites' Content, Insights Into Engagement, and Access

BACKGROUND

The Internet has become the primary information source for patients, with most turning to online resources before seeking medical advice.

OBJECTIVE

The aim of this study is to evaluate the quality of online information on hidradenitis suppurativa available to patients.

METHODS

The authors performed an Internet search using the search terms "hidradenitis suppurativa," "hidradenitis suppurativa treatment," "hidradenitis suppurativa surgery," and "acne inversa." They identified the initial 100 websites from Google, Yahoo, and Bing. Websites were evaluated based on the modified Ensuring Quality Information for Patients instrument.

RESULTS

Of the 300 websites, 95 (31.7%) were incorporated after accounting for the exclusion criteria: duplicate entries, websites not pertinent to the subject matter, websites inaccessible due to location restrictions or necessitating user accounts for access, websites in languages other than English, and websites originating from scientific publications directed at a scientific audience rather than the general population. Ensuring Quality Information for Patients scores ranged from 5 to 30/36, with a median of 17.

CONCLUSION

This analysis unveils a diverse array of websites that could confound patients navigating toward high-caliber resources. These barriers may hinder the access to top-tier online patient information and magnify disparities in referral rates, patient engagement, treatment satisfaction, and quality of life.

CD2 expressing innate lymphoid and T cells are critical effectors of immunopathogenesis in hidradenitis suppurativa

Hidradenitis suppurativa (HS) is a chronic, debilitating inflammatory skin disease with a poorly understood immunopathogenesis. Here, we report that HS lesional skin is characterized by the expansion of innate lymphocytes and T cells expressing CD2, an essential activation receptor and adhesion molecule. Lymphocytes expressing elevated CD2 predominated with unique spatial distribution throughout the epidermis and hypodermis in the HS lesion. CD2+ cells were mainly innate lymphocytes expressing the NK cell marker, CD56, and CD4+ T cells. Importantly, these CD2+ cells interacted with CD58 (LFA3) expressing epidermal keratinocytes and fibroblasts in the hypodermis. Granzyme Abright NKT cells (CD2+CD3+CD56bright) clustered with α-SMA expressing fibroblasts juxtaposed to epithelialized tunnels and fibrotic regions of the hypodermis. Whereas NK cells (CD2+CD56dim) were perforin+, granzymes A+ and B+, and enriched adjacent to hyperplastic follicular epidermis and tunnels of HS showing presence of apoptotic cells. The cytokines IL-12, IL-15, and IL-18, which enhance NK cell maturation and function were significantly elevated in HS. Ex vivo HS skin explant cultures treated with CD2:CD58 interaction-blocking anti-CD2 monoclonal antibody attenuated secretion of inflammatory cytokines/chemokines and suppressed inflammatory gene signature. Additionally, CD2:CD58 blockade altered miRNAs involved in NK/NKT differentiation and/or function. In summary, we show that a cellular network of heterogenous NKT and NK cell populations drives inflammation and is critical in the pathobiology of HS, including tunnel formation and fibrosis. Finally, CD2 blockade is a viable immunotherapeutic approach for the effective management of HS.

Increased risk of migraine among patients with hidradenitis suppurativa: A US multi-center cohort study

BACKGROUND

Hidradenitis suppurativa (HS) and migraine share common inflammatory pathways and neuropsychological implications. Both conditions involve proinflammatory cytokines like tumor necrosis factor and are associated with psychological comorbidities. Despite these similarities, the association between HS and migraine remained unclear. This study aimed to evaluate the relation between HS and incident migraine.

MATERIALS AND METHODS

We conducted a multicenter cohort study using the TriNetX Research Network. Patients diagnosed with HS between January 1, 2005 and December 31, 2022 were identified with a control group of non-HS subjects established by propensity score matching at a 1:1 ratio. Our outcome was the hazard ratio (HR) of incident migraine in relation to HS. We also examined the HR for various subtypes of migraine. We conducted stratified analyses based on age, gender, insomnia, depression, and anxiety subgroups. Sensitivity analyses were performed to strengthen the robustness of our analysis.

RESULTS

The HS group exhibited an increased risk of incident migraine compared to controls (HR 1.35, 95% confidence interval (CI) 1.28-1.42). Also, HS patients had increased risk of migraine with aura and migraine without aura than controls, with HR being 1.36 (95% CI 1.21-1.52), 1.36 (95% CI 1.20-1.45), respectively. Female HS patients demonstrated an increased risk of incident migraine compared to their controls (HR 1.38, 95% CI 1.30-1.45). Elevated risk of incident migraine was observed in both younger and older HS patients when compared to their respective controls. The increased risk of incident migraine among HS patients remained consistent across various sensitivity analyses.

CONCLUSIONS

HS patients present with an increased risk of incident migraine. Physicians should be aware of this association and provide timely referral and interventions when appropriate.

Apocrine Gland Damage and the Release of Specific Keratins in Early Stage Indicate the Crucial Involvement of Apocrine Glands in Hidradenitis Suppurativa

The apocrine glands (AGs) are not considered to be primarily involved in hidradenitis suppurativa (HS). This study investigated the potential role of AGs in HS pathogenesis using immunohistochemistry and single-cell sequencing of nonlesional skin and early lesional skin (LS) from patients with HS (n = 12) and healthy controls (n = 8). AG cell destruction was more frequent, and AG size was significantly reduced in the nonlesional skin and LS. Barrier-related genes (eg, CLDN1 and CDH1) were downregulated in the AGs of the nonlesional skin and LS. Damaged AGs in the LS primarily recruited and activated neutrophils through the CXCL-CXCR and SAA1-FPR2 pathways. Elevated levels of specific keratins (keratin 18 and keratin 19) released from damaged AGs were observed on the skin surface of patients and were associated with disease severity. Keratin 19 was also detected in the dermis of the nonlesional skin and LS and was surrounded by neutrophils and macrophages. Moreover, serum keratin 19 levels in patients (N = 20) were significantly negatively correlated with the age at HS onset. Collectively, our findings provide previously unreported evidence that the AGs are damaged and release specific keratins in early HS lesions, indicating a crucial role of the AGs in HS pathogenesis.

The variant c.274A>G (p.Asn92Asp) in KRT17 in a patient with pachyonychia congenita and a novel clinical feature of acne inversa

Introduction

The occurrence of pachyonychia congenita (PC) and acne inversa (AI) may be related to gene mutations. The aim of this study is to identify the genetic cause in a patient with PC and AI, and to explore the possible molecular mechanism of their co-occurrence.

Methods

The clinical data of the proband were collected, and the genomic DNA of the proband and unaffected parents were extracted. The variant sites of the proband were identified by whole-exome sequencing, and then the variant sites of the proband and his parents were verified by Sanger sequencing.

Results

A heterozygous variant in KRT17 gene was found in the patient, resulting in a missense amino acid variant (p.N92D). The variant was not found in his parents or 100 unrelated healthy controls. In addition, this variant was not found in the gnomad v4 database. The three-dimensional structure analysis of the protein suggested that the polarity of amino acids changed after the variant. After lentiviral plasmid transfection into HaCaT cells, the expression level of NOTCH signaling decreased in the constructed c.274A>G (p.Asn92Asp) of KRT-17 mutant cells compared to that in the wild-type. Subsequent verification confirmed that differences in the expression levels of p-PI3K, AKT and p-AKT between the groups were not statistically significant.

Discussion

Although this variant has been reported previously, our findings could expand the spectrum of co-occurrence of PC and AI with KRT17 gene variants, and elucidated the possible pathogenesis at the protein level, thereby laying a foundation for the genetic diagnosis and genetic counseling provided to individuals with PC.

Gender, race, and economic factors influencing screening practices in hidradenitis suppurativa: a cross-sectional analysis

Hidradenitis suppurativa (HS) is a chronic inflammatory skin condition that significantly impacts patients' quality of life. Despite its substantial burden, HS remains underdiagnosed and undertreated, particularly among marginalized populations. This study aimed to elucidate the primary social determinants of health (SDOH) and structural determinants of health (StDOH) influencing rates and patterns of screening for patients diagnosed with HS. Using data from the All of Us Research Program database, participants with HS were identified using ICD-10 codes and stratified based on various sociodemographic factors, including race, gender, and income. The primary outcome variables were participation in viral screening and disease screening among HS patients. Statistical analyses were performed to assess the relationship between sociodemographic factors and screening practices. Income and gender had significant impacts on screening practices. Higher-income patients were more likely to receive necessary disease screening and less likely to receive unnecessary disease screening compared to lower-income patients. Non-male patients had significantly higher rates of unnecessary disease and viral screening than male patients. While differences in screening practices within each income level were significant, there were no significant differences across different income brackets or racial groups. These findings suggest that subjectivity associated with individual physicians' recommendations may contribute to disparities in screening outcomes, especially in lower-income and non-male HS patients. The study highlights the need for more clearly delineated screening guidelines and continued research on the role of SDOH in improving patient health outcomes.