Characterization of Hidradenitis Suppurativa Phenotypes: A Multidimensional Latent Class Analysis of the National Italian Registry IRHIS

Anti-IL17 Secukinumab in hidradenitis suppurativa: A long-term drug survival analysis

Real-world data on the long-term effectiveness of the anti-IL17 agent secukinumab in treating moderate-to-severe Hidradenitis suppurativa (HS) are lacking. In this study, 24 patients with moderate-severe HS received five weekly subcutaneous injections followed by maintenance doses every 4 weeks. Primary outcomes included HiSCR, IHS4 reduction, and DLQI measures assessed at 12-week intervals. The median secukinumab drug survival was 16.0 months (range 3-51), with a 56.5% maximal response rate at 6 months and dropout exceeding 40% at 1 year. Baseline disease burden emerged as a key predictor of treatment response, overshadowing factors like sex or BMI. Prior systemic steroid use negatively impacts drug survival. The study underscores the critical 6-month window for assessing treatment efficacy, emphasizing the importance of initial induction dosing. Additionally, the newly developed scoring system, IHS4-55, showed analogies to the older HiSCR score in capturing treatment response. In this real-life scenario, challenges persist in HS management, necessitating innovative therapeutic approaches and predictive markers.

Can telomeric changes orchestrate the development of autoinflammatory skin diseases?

Telomeres, the safeguarding caps at the tips of chromosomes, are pivotal in the aging process of cells and have been linked to skin ailments and inflammatory conditions. Telomeres undergo a gradual reduction in length and factors such as oxidative stress hasten this diminishing process. Skin diseases including inflammatory conditions can be correlated with the shortening of telomeres and the persistent activation of DNA damage response in skin tissues. Telomere dysfunction could disrupt the balance of the skin, impairs wound healing, and may contribute to abnormal cytokine production. Skin aging and processes related to telomeres may function as one of the triggers for skin diseases. The presence of proinflammatory cytokines and dysfunctional telomeres in conditions such as Dyskeratosis Congenita implies a possible connection between the shortening of telomeres and the onset of chronic inflammatory skin disorders. In autoinflammatory skin diseases, chronic inflammation hinders wound healing thus aggravating the progression of the disease. The NF-ĸB pathway might contribute to the initiation or progression of chronic disorders by influencing mechanisms associated with telomere biology. The intricate connections between telomeres, telomerase, telomere-associated proteins, and skin diseases are still a complex puzzle to be solved. Here, we provide an overview of the impact of telomeres on both health and disease with a specific emphasis on their role in skin, inflammation and autoinflammatory skin disorders.

Hidradenitis suppurativa: new insights into disease mechanisms and an evolving treatment landscape

Hidradenitis suppurativa (HS), also known as acne inversa, is a chronic disabling and debilitating inflammatory disease with a high unmet medical need. The prevalence of HS reported in most studies is 1-2%, although it is likely to be under-reported and estimates vary globally owing to variance in data collection methods, ethnicity, geographical location and under-diagnosis. HS is characterized by persistent, painful cutaneous nodules, abscesses and draining tunnels commonly affecting the axillary, anogenital, inguinal and perianal/gluteal areas. Over time, chronic uncontrolled inflammation results in irreversible tissue destruction and scarring. Although the pathophysiology of HS has not been fully elucidated, the tumour necrosis factor (TNF)-α and interleukin (IL)-17 pathways have an important role, involving multiple cytokines. Currently, treatment options include topical medications; systemic therapies, including repeated and/or rotational courses of systemic antibiotics, retinoids and hormonal therapies; and various surgical procedures. The anti-TNF-α antibody adalimumab is currently the only biologic approved by both the US Food and Drug Administration and the European Medicines Agency for HS; however, its efficacy varies, with a clinical response reported in approximately 50% of patients in phase III trials. HS is a rapidly evolving field of discovery, with a diverse range of agents with distinct mechanisms of action currently being explored in clinical trials. Several other promising therapeutic targets have recently emerged, and agents targeting the IL-17 and Janus kinase (JAK)/signal transducer and activator of transcription (STAT) pathways are the most advanced in ongoing or completed phase III clinical trials. Alongside limited therapeutic options, significant challenges remain in terms of diagnosis and disease management, with a need for better treatment outcomes. Other unmet needs include significant diagnostic delays, thus missing the therapeutic 'window of opportunity'; the lack of standardized outcome measures in clinical trials; and the lack of established, well-defined disease phenotypes and biomarkers.

Hidradenitis suppurativa: Detangling phenotypes and identifying common denominators

Hidradenitis suppurativa (HS) is a chronic inflammatory skin disease with a severe impact on patients' quality of life through its recurrent and painful nature, as well as its comorbidity burden. The shift in the pathogenic paradigm from a condition of the apocrine glands to an autoinflammatory disease associated with follicular destruction has rendered its understanding difficult, as there are still large gaps in pinpointing the underlying mechanisms, which cannot currently explain the existing clinical variation and as a result, translate into suboptimal therapy. Multifactorial involvement is hypothesized, with an implication of genetic mutations, microbiome dysbiosis, cytokine upregulation and environmental factors. Clinical observation is fundamental for diagnosis, however, the marked heterogeneity in presentation leads to delays in detection and challenges in treatment selection, showcasing clear limits in defining the link between genetic aspects of HS, the role of epigenetic factors and its pathogenic pathways. There have been attempts to formulate phenotypes that could aid in prognostication and management, however, current classification schemata show significant overlap and no validation through longitudinal studies. In this context, nomenclature poses a great challenge due to the lack of global agreement in the definition of lesions, which should be addressed by future research to enable simplified recognition and allow for more precise severity scoring. This could be complemented by the addition of extra dermatologic findings or paraclinical assessment in constructing phenotypes. The development of valid, predictive and reliable classifications of HS may lead to an improvement in comprehending its pathophysiology, favouring a more personalized approach in management. This could be achieved through consensus in the characterization of clinical features and data gathering, as well as validation attempts for described phenotypes. Ultimately, the genotype-endotype-phenotype correlation in HS requires targeted, systematic inquiries and should be addressed more largely to broaden the perspective on this debilitating entity.

Clinical Features and Response to Treatment in Elderly Subjects Affected by Hidradenitis Suppurativa: A Cohort Study

Hidradenitis suppurativa (HS) is a chronic-relapsing inflammatory skin disease. It usually appears in the second and third decades, but a smaller proportion of patients develop late-onset HS. Geriatric HS, defined as the persistence or the development of HS after the age of 65 years, has been poorly explored. This study aimed to investigate the clinical features, treatment management and response to therapies of HS elderly subjects (≥65 years old). We designed a multicentric observational study, gathering data from seven Italian university hospitals. Demographic and clinical data of HS patients aged over 65 years were collected at baseline, week 12 and week 24. Overall, 57 elderly subjects suffering from HS were enrolled. At baseline, disease severity was predominantly moderate-to-severe, with 45.6% of patients classified as Hurley III. The gluteal phenotype was the most frequently observed; it also appeared to affect patients' quality of life more than other phenotypes. Gluteal involvement was detected in about half (49.1%) of cases and associated with severe stages of the disease. In terms of therapeutic response, Hurley III patients showed the persistency of higher values of mean IHS4, DLQI, itch- and pain-NRS scores compared to Hurley I/II. In conclusion, disease severity in this subpopulation appears high and treatment is often challenging.

Association between Hidradenitis Suppurativa and Abnormalities in Semen Parameters and Sexual Function: A Pilot Study

Hidradenitis suppurativa (HS) is a chronic inflammatory skin disease affecting patients of reproductive age. Although HS shares risk factors with male infertility, only 1 epidemiological study has evaluated this association. To further evaluate this potential association, findings on semen and hormonal analysis, testicular ultrasound, and the International Index of Erectile Function (IIEF-15) were compared between 28 men attending a tertiary HS clinic during the period April 2019 to April 2021, and 44 healthy controls, spouses of infertile women undergoing semen evaluation before in vitro fertilization. Patients with HS were divided based on the absence or presence of gluteal and genital lesions. Patients with HS were younger than controls (median 27 vs 34 years, p < 0.0004) and had a higher proportion of smokers (86% vs 33%, p < 0.0001). Semen parameters in patients with gluteal-genital lesions, specifically those with severe scrotal involvement necessitating surgery, were lower than the WHO reference values and significantly lower than in patients without gluteal-genital lesions and controls. Erectile dysfunction was reported by 93% of patients with HS. These findings suggest that spermatogenesis and sexual function may be impaired in young men with HS. Therefore, multidisciplinary management of HS should include their evaluation to identify patients who might benefit from semen cryopreservation and sexual treatment.

Pilonidal Sinus Disease is Associated with Severe Hidradenitis Suppurativa in a Spanish Cohort

Hidradenitis suppurativa is a chronic inflammatory disorder of the hair follicle with a high level of morbidity. Pilonidal sinus disease is a comorbid disorder and may be the reason for first contact with the healthcare system of patients with hidradenitis suppurativa. The aim of this study was to evaluate the frequency of association of pilonidal sinus disease and hidradenitis suppurativa and to explore whether pilonidal sinus disease defines a different clinical profile for patients with hidradenitis suppurativa. A cross-sectional study in which data regarding past history of pilonidal sinus disease, clinical and sociodemographic information were recorded during the first visit to the Hidradenitis Suppurativa Clinic of 2 tertiary hospitals. A total of 839 patients were included in the study. Of these, 51.7% (434/839) were male and mean age was 37.3 ± 13.6 years. Pilonidal sinus disease was present in 32.6% (269/839) of the patients and was associated with an early debut of hidradenitis suppurativa, a higher Hurley stage, inflammatory phenotype and a greater number of fistulas and perianal involvement. Elapsed time between pilonidal sinus disease and diagnosis of hidradenitis suppurativa was associated with higher disease severity. Pilonidal sinus disease is a frequent comorbidity and risk marker for hidradenitis suppurativa disease severity. Pilonidal sinus disease could be a sentinel event to identify patients who would benefit from close treatment and follow-up.

Targeting the NLRP3 inflammasome reduces inflammation in hidradenitis suppurativa skin

BACKGROUND

Treatment for the debilitating disease hidradenitis suppurativa (HS) is inadequate in many patients. Despite an incidence of approximately 1%, HS is often under-recognized and underdiagnosed, and is associated with a high morbidity and poor quality of life.

OBJECTIVES

To gain a better understanding of the pathogenesis of HS, in order to design new therapeutic strategies.

METHODS

We employed single-cell RNA sequencing to analyse gene expression in immune cells isolated from involved HS skin vs. healthy skin. Flow cytometry was used to quantify the absolute numbers of the main immune populations. The secretion of inflammatory mediators from skin explant cultures was measured using multiplex and enzyme-linked immunosorbent assays.

RESULTS

Single-cell RNA sequencing analysis identified a significant enrichment in the frequency of plasma cells, T helper (Th) 17 cells and dendritic cell subsets in HS skin, and the immune transcriptome was distinct and more heterogeneous than healthy skin. Flow cytometry revealed significantly increased numbers of T cells, B cells, neutrophils, dermal macrophages and dendritic cells in HS skin. Genes and pathways associated with Th17 cells, interleukin (IL)-17, IL-1β and the NLRP3 inflammasome were enhanced in HS skin, particularly in samples with a high inflammatory load. Inflammasome constituent genes principally mapped to Langerhans cells and a subpopulation of dendritic cells. The secretome of HS skin explants contained significantly increased concentrations of inflammatory mediators, including IL-1β and IL-17A, and culture with an NLRP3 inflammasome inhibitor significantly reduced the secretion of these, as well as other, key mediators of inflammation.

CONCLUSIONS

These data provide a rationale for targeting the NLRP3 inflammasome in HS using small-molecule inhibitors that are currently being tested for other indications.

Hidradenitis suppurativa from the typical patient to the new clinical phenotypes

Hidradenitis suppurativa (HS) is a clinically heterogeneous disease with a broad spectrum of clinical features. Attempts to classify HS into distinct clinical phenotypes could lead to a better understanding of the condition and the development of individualized treatment protocols. We summarize some of the existing phenotype classifications and present our experience with 250 patients and their many clinical presentations. We have emphasized the pathophysiologic and clinical overlap between HS and pyoderma gangrenosum. The more severe presentations can include erosive and ulcerative lesions, sometimes associated with vegetative changes leading to diagnostic quandaries. We propose a new phenotype of pyoderma gangrenosum-like HS in which painful ulcerative or vegetative lesions appear in sites affected by HS, their activity coincides with the flareups of classic inflammatory manifestations of HS, and they heal with cribriform or atrophic scars.

Can hidradenitis suppurativa patients classify their lesions by means of a digital lesion identification scheme?

BACKGROUND AND OBJECTIVES

Hidradenitis suppurativa (HS) differs widely with respect to its clinical presentation. Literature imposes different phenotypes potentially implying different treatment modalities. The aim of this study is to develop a validated scheme that enables HS patients to identify their own lesion types.

PATIENTS AND METHODS

The developed schemes for physicians and patients were implemented in a specific software. Upon patient consent, the physician used the software to document the lesions identified. Patients subsequently logged into the patient-version of the software from the convenience of their home and selected the lesions they identified on themselves. Afterwards the correlation between professionals and patients was tested.

RESULTS

For seven lesion types, correlation coefficients were statistically significant. A large/strong correlation between patients and physicians was found for the draining fistulas (0.59) and double-ended comedones (0.50). For five other lesion types, correlation was medium/moderate, namely the inflammatory nodule (0.37), abscess (0.30), accordion like-/ bridged scar (0.45), epidermal cyst (0.33) and pilonidal sinus (0.39).

CONCLUSIONS

HS-patients demonstrate high willingness to share their experiences and data. Therefore, a self-assessment scheme, as the developed LISAI, can be a valuable tool to enrich patient surveys with the identification of lesion types, for instance as a basis for phenotyping.

On the definition of dermatological disease. Part 2: approaches for defining dermatological diseases

In Part 1 of this two-part review, conceptual frameworks for defining skin diseases were articulated. In this review, the main approaches that can be used to develop diagnostic criteria for skin disease are summarized, using atopic dermatitis (AD) as an example. Different frameworks for defining skin disease for research purposes are articulated, including statistical, prognostic, operational, clinical and epidemiological approaches. All share the common aim of attempting to develop criteria that enable meaningful comparisons between groups of people. The desirable attributes of a good definition are described: diagnostic criteria should measure what they are meant to measure; the results should be the same for different assessors; the criteria should be coherent with what is known about that disease; they should reflect some degree of morbidity and not pick up subclinical disease; they should be easy to administer; and they should be applicable to a range of people of different ages, sexes/genders and ethnicities. Consensus-based criteria are contrasted with epidemiological derivation methods that assess the performance of diagnostic criteria in relation to a reference standard. The sensitivity and specificity of a disease definition is explained, along with how the trade-off between these two properties can vary, depending on the purpose of the study and the study setting. The review closes with some reflections on when it is appropriate to consider splitting a disease into more than one category and how diagnostic criteria can be interpreted in the clinical setting.

Register, multicenter and genome-wide association studies in hidradenitis suppurativa

The European Hidradenitis Suppurativa Foundation (EHSF) e.V. has taken several initiatives to collaborative studies. They result from the data of the European Registry of Hidradenitis Suppurativa (ERHS) based on the knowledge obtained from the regional Northern countries (HISREG) and Italian (IRHIS) registries and the real-world data generated from claims data from insurance databases. Multicenter studies, such as the Hidradenitis Suppurativa collaborative study of subtypes (HORUS) and the Global Hidradenitis Suppurativa Atlas (GHISA) are planned to provide an ideal complement to the register studies. Most recently, the role of EHSF as a coordinator or key player is being explored in multiple genetic studies, such as a genome-wide association study (GWAS) and the exome sequencing and cellular/molecular profiling project, which will speed up gene and drug discovery in HS.

Insights into hidradenitis suppurativa

Hidradenitis suppurativa (HS) is a chronic, debilitating, inflammatory skin disorder with a prevalence of around 1% and a profound impact on patients' quality of life. Characteristic lesions such as inflammatory nodules, abscesses, and sinus tracts develop in the axillae, inguinal, and gluteal areas, typically during or after puberty. A complex interplay of genetic predisposition, hormonal factors, obesity, and smoking contributes to development and maintenance of the disease. HS is considered to arise from an intrinsic defect within the hair follicle, leading to follicular plugging, cyst formation, and subsequent rupture that in turn induce an acute inflammatory response characterized by elevated levels of IL-1β, IL-17, and TNF. Over time, acute lesions transition into chronic disease, with active draining sinus tracts accompanied by extensive fibrosis. HS is associated with other immune-mediated inflammatory diseases, metabolic and cardiovascular disorders, and psychiatric comorbidities. Treatment of HS often requires a combination of antibiotic or immunosuppressing therapies and surgical intervention. Nonetheless, the currently available treatments are not universally effective, and many drugs, which are often repurposed from other inflammatory diseases, are under investigation. Studies into the early stages of HS may yield treatments to prevent disease progression; yet, they are hampered by a lack of appropriate in vitro and animal models.

Mediterranean diet, lifestyle and quality of life in Sardinian patients affected with Hidradenitis suppurativa

Background: Hidradenitis Suppurativa is a chronic inflammatory skin disease with a strong negative impact on physical and psychological health. Obesity, especially visceral adiposity, but also smoking or unhealthy nutritional habits, have been reported to be significantly associated with hidradenitis suppurativa.

Design and methods: Case-control study in 35 patients of both sexes affected with hidradenitis suppurativa, and 35 healthy subjects matched for sex, age, and geographic origin (Sardinia, Italy).

Results: Several anthropometric measures (body mass index, waist circumference, body composition), lifestyle (Mediterranean diet adherence, and physical activity level), and the perceived physical and mental health status were evaluated in case and controls. Hidradenitis patients showed significantly higher values of body mass index, waist circumference, body composition, fat mass, and lower values of physical and mental health status compared to controls, while both groups showed a similar moderate physical activity level which can be assumed to counteract the negative effects of obesity or poor nutritional pattern in hidradenitis patients. However, none of the evaluated variables were correlated with the severity of the disease, assessed by means of the Hurley stage system or the Sartorius score. Instead, the Sartorius score showed a positive correlation with the duration of hidradenitis, mainly imputable to the diagnostic delay and the consequent long lasting inflammatory status.

Conclusions: Although nutritional factors and lifestyle can be important and modifiable factors in the hidradenitis suppurativa course, the detrimental effect of chronic inflammation and delayed management are clearly prevalent and heavily influence the disease burden.

Unraveling the Heterogeneity of Hidradenitis Suppurativa with Phenotype Schema

One of the major challenges faced with hidradenitis suppurativa (HS) is the variability in manifestations and treatment responses. Cazzaniga et al. (2020) conducted a cross-sectional study and latent class analysis to explain disease heterogeneity and formulate HS phenotypes. HS phenotypes might be useful for disease or treatment outcomes. Future studies should assess rater reliability and predictive validity for outcomes such as treatment response or disease progression.

Seven Years-Experience of adalimumab therapy for hidradenitis suppurativa in a real-life dermatologic setting

INTRODUCTION

Hidradenitis Suppurativa (HS) often causes severe impairment of the quality of life of patients affected, as it is characterized by recurrent relapses of inflammation and predisposes to retractive scars, with severe alteration of anatomy of the affected regions. Adalimumab is currently the only approved long-term biological therapy for this disease.

MATERIAL AND METHOD

we retrospectively review the data of HS patients treated with Adalimumab at the "Hidradenitis Suppurativa Clinic", University of Ferrara, Italy since the drug was first available to October 2020. The aim is to describe our real-life experience in a clinical outpatient service. We assessed the main demographic features, therapy duration, reasons of suspension and efficacy (evaluated by HiSCR - Hidradenitis Score) in relation to surgical procedures, hospitalization, number of areas involved by the disease and BMI >30. We also assessed the aspects related to the use of adalimumab's biosimilar.

RESULTS

data on 76 patients, with a mean age of 38.26 ± 14.74 years and mean BMI 28.10 ± 5.92 were collected. Most of the treated patients had Hurley stage III (58/76); mean Sartorius score was 115.5 ± 55.86, mean IHS4 was 76.1 ± 44.3. A statistically significant correlation between hospitalization and cessation of adalimumab, the loss of the achievement of the HiSCR, and surgery was found. No need to do surgery was a protective factor against the failure of adalimumab treatment, meaning that the most severe cases are more likely to fail the biological therapy.

CONCLUSION

new scenarios are opening up in clinical practice: the arrival of biosimilars allow greater sustainability of expenditure, while the anti-IL17 allow the patient who has failed therapy with adalimumab a valid and safe therapeutic option to be undertaken. A comprehensive care including hospitalization, a specific antibiotic therapy and surgical treatment is often mandatory to achieve a satisfactory control of the disease.