An Update on Medical Treatment Options for Hidradenitis Suppurativa

Taiwanese Dermatological Association (TDA) consensus recommendations for the definition, classification, diagnosis, and management of hidradenitis suppurativa

Hidradenitis suppurativa (HS) is a chronic inflammatory follicular disease characterized by painful, recurrent, inflamed lesions most commonly occurring in the axillary, inguinal, and anogenital regions. HS can inflict immense physical and psychological impact on patients who suffer from this distressing disease. Management of HS generally requires combining various medical and procedural treatment modalities; however, the disease is often recalcitrant to conventional treatments. In light of recent evidence supporting the effectiveness of biologic agents in the treatment of HS, the Taiwanese Dermatological Association established an expert panel of nine dermatologists to develop consensus statements aimed to provide up-to-date evidence-based guidance in optimizing HS patient management in Taiwan. The recommendations described in the statements were summarized in a management algorithm in terms of general care, topical treatment, systemic treatment, and procedural treatment.

Treatment Patterns and Healthcare Resource Utilization Among Newly Diagnosed Psoriasis, Psoriatic Arthritis, Axial Spondyloarthritis, and Hidradenitis Suppurativa Patients with Past Diagnosis of an Inflammatory Condition: A Retrospective Cohort Analysis of Claims Data in the United States

INTRODUCTION

Psoriasis (PSO), psoriatic arthritis (PsA), axial spondyloarthritis (axSpA), and hidradenitis suppurativa (HS) are chronic inflammatory diseases (CIDs) often diagnosed and treated individually. However, genetic overlaps exist among CIDs, and patients with one are at risk of developing others within the same spectrum. This analysis characterized treatment patterns along with clinical and economic burdens of newly diagnosed CIDs among patients with an additional past diagnosis of PSO, PsA, axSpA, or HS.

METHODS

This study used MarketScan® databases to examine demographics, treatment patterns, and healthcare resource utilization for patients with ≥ 1 claim for PSO or HS or ≥ 2 claims for PsA or axSpA, and continuous enrollment in the year before (baseline period) and following (follow-up period) the date of first diagnosis (incident diagnosis). Comorbidities and new CID diagnoses with a past diagnosis of PSO, PsA, axSpA, or HS, were examined.

RESULTS

The analysis included 298,794 patients (maximum of 1202 patients with ≥ 1 incident diagnoses): 134,233 had incident PSO; 9914 had incident PsA; 115,194 had incident axSpA; and 40,655 had incident HS. Prevalence of ≥ 1 CID diagnosis among patients with past diagnosis of PSO, PsA, axSpA, or HS was 4959/134,233 (3.7%), 5256/9914 (53.0%), 3205/115,194 (2.8%), and 1180/40,655 (2.9%), respectively. In patients with incident axSpA and past PsA diagnosis, incident axSpA and past HS diagnosis, and incident HS and past PSO diagnosis, steroid and opioid use were high across baseline and follow-up periods and use of biologic disease-modifying antirheumatic drugs increased from baseline to follow-up. Disease-related costs increased absolutely and increased or remained high as a proportion of all-cause costs.

CONCLUSION

Patients with newly diagnosed CIDs and additional past diagnosis of PSO, PsA, axSpA, or HS experienced high treatment utilization and healthcare costs. These findings highlight the need for payers, health technology assessment agencies, clinicians, and other stakeholders to explore the co-management of CIDs, rather than treating them separately.

Real-World Findings on the Characteristics and Treatment Exposures of Patients with Hidradenitis Suppurativa from US Claims Data

INTRODUCTION

Hidradenitis suppurativa (HS) is a chronic, debilitating, and painful inflammatory skin disease that significantly and negatively impacts patients' quality of life. The prevalence of HS in the USA is estimated to be 0.10%, with worldwide reports suggesting a prevalence closer to 1%. There is limited real-world evidence available on the care of patients with HS. We aimed to evaluate the trends in clinical care and treatment in the patient population with HS in the USA in a real-world setting.

METHODS

A cohort study was conducted using claims data from IBM MarketScan Databases, including the US Commercial Claims and Encounters with Medicare Supplemental and Coordination of Benefits (CCAE+MDCR) database and IBM US Medicaid database.

RESULTS

The annual prevalence of HS increased from 0.06% (2008) to 0.14% (2017), and from 0.17% (2008) to 0.31% (2017) among CCAE+MDCR and Medicaid patients, respectively. Dermatologist visits increased from 31.9% (2008) to 47.8% (2019) in CCAE+MDCR patients, and decreased from 10.9% (2008) to 8.5% (2018) in Medicaid patients. Opioid use decreased from 45.4% (2008) to 25.5% (2019) among CCAE+MDCR patients, and from 71.3% (2008) to 48.1% (2018) among Medicaid patients. Only 8.4% of CCAE+MDCR patients and 5.8% of Medicaid patients were exposed to any biologic in 2018.

CONCLUSIONS

Improved care and treatment of HS over the last decade, including the emergence of new treatments, have been accompanied by an increase in awareness and reported prevalence of the disease. However, there are still gaps in access to dermatologic care and low utilization of biologic therapies among patients with HS. INFOGRAPHIC.

Drug Survival of Oral Retinoids in Hidradenitis Suppurativa: A Real-Life Cohort Study

INTRODUCTION

Cohort studies on the use of retinoids for hidradenitis suppurativa (HS) have yielded contradicting results. As the clinical presentation of HS is heterogeneous, with different predilection sites and hallmark features, it can be hypothesized that HS phenotypes are associated with the effectiveness of specific retinoid treatments.

OBJECTIVES

The aim of this study was to evaluate the drug survival of oral retinoids in the treatment of HS and to establish predictors for longer treatment duration.

METHODS

A retrospective, dual-center study was conducted in the Netherlands in adult HS patients treated with oral retinoids between 2011 and 2021. Drug survival analyses were performed through Kaplan-Meier survival curves. Additionally, Cox regression models were used to determine predictors for a longer drug survival.

RESULTS

In total, 102 patients were included. Overall drug survival of (low-dose) isotretinoin (n = 66) at 12 and 24 months was 44.2% and 15.5%, respectively. Termination of treatment was mostly due to ineffectiveness (26%). Presence of widespread comedones (p = 0.03) and the use of concomitant systemic medication (p = 0.04) were associated with a prolonged treatment duration. For acitretin (n = 36), the overall drug survival was 42.0% at 12 months and 37.4% at 24 months, and was also predominantly determined by ineffectiveness (28%). Interestingly, the scarring folliculitis phenotype (p < 0.05) was associated with prolonged drug survival time for acitretin treatment relative to the regular phenotype.

CONCLUSION

Comparable drug survival rates at 12 months for isotretinoin and acitretin were found. HS patients with widespread comedones and the scarring folliculitis phenotype could benefit from treatment with isotretinoin or acitretin, respectively.

Immunomodulatory Drugs in the Treatment of Hidradenitis Suppurativa—Possibilities and Limitations

Hidradenitis suppurativa, also known as acne inversa, is a chronic, progressive, debilitating, recurrent inflammatory skin disease characterized by the occurrence of very severe, persistent, painful nodules, abscesses, and fistulas, most commonly found in the skin folds of the axilla, groin, gluteal, and perianal areas. Treatment is rather difficult and typically requires the use of multiple modalities. Regardless of the presence of several therapeutic options, treatment often turns out to be ineffective or poorly selected concerning the clinical picture of the disease. Thus, the search for new biologics and other target treatments of hidradenitis suppurativa is ongoing. The safety and efficacy of adalimumab, still the only U.S. Food and Drug Administration approved biologic in the hidradenitis suppurativa treatment, paved the way for new drugs to be compared with it. Several more drugs with new immunological targets are currently under investigation for the treatment of acne inversa. The aim of the article was to present the current and future targets of acne inversa treatment, simultaneously providing insights into the molecular pathomechanisms of the disease.

Practical Guidelines for Managing Patients With Hidradenitis Suppurativa: An Update

Hidradenitis suppurativa (HS) is a chronic, inflammatory skin disease that is characterized by the formation of comedones, papules, nodules, abscesses and sinus tracts in the axillary, inframammary, groin, and gluteal areas. Up to 3.8% of the Canadian population has HS, though due to a lack of awareness of HS, many patients are initially misdiagnosed and do not receive adequate treatment early on in the disease course. Once a diagnosis of HS is made, developing an effective management plan can be a dilemma for many providers. There is significant variability in response to any given therapy within the HS patient population and many HS patients have other medical comorbidities which must be taken into consideration. The aim of this review is to provide a practical approach for all healthcare providers to diagnose and manage HS and its associated comorbidities. A sample electronic medical record template for HS management was developed by the Canadian Hidradenitis Suppurativa Foundation Executive Board and is intended for use in clinical settings. This will help to increase collaboration between primary healthcare providers, dermatologists, and other medical specialists and ultimately improve the quality of care that HS patients receive.

Sarecycline Demonstrates Clinical Effectiveness against Staphylococcal Infections and Inflammatory Dermatoses: Evidence for Improving Antibiotic Stewardship in Dermatology

Tetracycline class antibiotics are widely used for multiple skin diseases, including acne vulgaris, acne rosacea, cutaneous infections, inflammatory dermatoses, and autoimmune blistering disorders. Concerns about antibiotic resistance and protecting the human/host microbiome beg the question whether broad-spectrum tetracyclines such as doxycycline and minocycline should be prescribed at such a high rate by dermatologists when a narrow-spectrum tetracycline derivative, sarecycline, exists. We evaluated the clinical effectiveness of oral sarecycline against cutaneous staphylococcal infections, eyelid stye, and mucous membrane pemphigoid to determine whether sarecycline is a viable option for clinicians to practice improved antibiotic stewardship. We observed significant improvement in staphylococcal infections and inflammatory dermatoses with courses of oral sarecycline as short as 9 days, with no reported adverse events. These clinical findings are consistent with in vitro microbiological data and anti-inflammatory properties of sarecycline. Our data provides a strong rationale for clinicians to use narrow-spectrum sarecycline rather than broad-spectrum tetracyclines as a first-line agent in treating staphylococcal skin infections and inflammatory skin diseases for which tetracyclines are currently commonly employed. Such advancement in the practice paradigm in dermatology will enhance antibiotic stewardship, reduce risk of antibiotic resistance, protect the human microbiome, and provide patients with precision medicine care.

An integrative network-based approach for drug target indication expansion

BACKGROUND

The identification of a target-indication pair is regarded as the first step in a traditional drug discovery and development process. Significant investment and attrition occur during discovery and development before a molecule is shown to be safe and efficacious for the selected indication and becomes an approved drug. Many drug targets are functionally pleiotropic and might be good targets for multiple indications. Methodologies that leverage years of scientific contributions on drug targets to allow systematic evaluation of other indication opportunities are critical for both patients and drug discovery and development scientists.

METHODS

We introduced a network-based approach to systematically screen and prioritize disease indications for drug targets. The approach fundamentally integrates disease genomics data and protein interaction network. Further, the methodology allows for indication identification by leveraging state-of-art network algorithms to generate and compare the target and disease subnetworks.

RESULTS

We first evaluated the performance of our method on recovering FDA approved indications for 15 randomly selected drug targets. The results showed superior performance when compared with other state-of-art approaches. Using this approach, we predicted novel indications supported by literature evidence for several highly pursued drug targets such as IL12/IL23 combination.

CONCLUSIONS

Our results demonstrated a potential global approach for indication expansion strategies. The proposed methodology enables rapid and systematic evaluation of both individual and combined drug targets for novel indications. Additionally, this approach provides novel insights on expanding the role of genes and pathways for developing therapeutic intervention strategies.

Reproductive Potential and Outcomes in Patients with Hidradenitis Suppurativa: Clinical Profile and Therapeutic Implications

There are scarce data available regarding the impact of hidradenitis suppurativa (HS) on fertility, course and outcome of pregnancy and risk associated with treatments. The aims of this study are (1) to describe the clinical profile of HS women of childbearing age with and without accomplished reproductive desires and (2) to describe the prescribed treatments based on the fulfillment of reproductive intentions. We conducted a prospective observational study that included 104 HS women of childbearing age, 50.96% (53/104) with unfulfilled reproductive desires. These women were younger (29.08 vs. 42.06 years, p < 0.001), less frequently married and higher educated than women with fulfilled reproductive desires. Their age of disease onset was lower, but disease duration was shorter, in concordance with a lower International Hidradenitis Suppurativa Severity Score System (IHS4) and lower number of draining tunnels. Combined oral contraceptives were more frequently prescribed in women with unfulfilled reproductive desires (30.19% vs. 9.80%, p = 0.013) while biologics were less used in this group (3.77% vs. 13.73%, p = 0.08). In conclusion, a higher educational level and an earlier disease onset, with potential implications in finding a partner, may make the fulfillment of reproductive desires difficult for patients with HS. This study could help clinicians to achieve a better understanding of the specific characteristics of HS during childbearing age and consider reproductive desires when making treatment decisions.

Is There a Role for Therapeutic Drug Monitoring in Patients with Hidradenitis Suppurativa on Tumor Necrosis Factor-α Inhibitors?

Tumor necrosis factor-α inhibitors, adalimumab and infliximab, are at the forefront of biologic therapy for the management of moderate-to-severe hidradenitis suppurativa, with adalimumab as currently the only approved medication for this condition. In treating patients, primary or secondary lack of response (also termed suboptimal response) is a major burden for both patients and healthcare systems and is a challenge with biologics in part owing to the development of anti-drug antibodies following treatment. To overcome this, therapeutic drug monitoring may be conducted proactively or reactively to a patient's suboptimal response guided by measurements of trough serum drug concentrations and levels of anti-drug antibodies. While strong evidence to support the utility of therapeutic drug monitoring exists in patients with inflammatory bowel disease, current information is limited in the context of hidradenitis suppurativa. We sought to summarize the available evidence and to present the role of therapeutic drug monitoring and other dose optimization strategies in improving clinical response in patients with hidradenitis suppurativa treated with tumor necrosis factor-α inhibitors.

A Molecular Perspective on the Potential Benefits of Metformin for the Treatment of Inflammatory Skin Disorders

Due to its anti-hyperglycemic effect, metformin is the first-line medication for the treatment of type 2 diabetes, particularly in people who are obese. However, metformin is a drug with a very wide range of pharmacological properties and reports of its therapeutic effect on diseases including inflammation and cancer are increasing. Numerous research groups have reported that metformin has beneficial effects on a variety of inflammatory skin disorders including psoriasis, acanthosis nigricans, acne, hidradenitis suppurativa, and allergic contact dermatitis. According to these reports, in addition to the well-known action of metformin, that is, its anti-hyperglycemic effect, NF-kB inhibition and the resulting alteration to the cytokine network may be the potential targets of metformin. Its anti-hyperandrogenism effect has also been confirmed as the major action of metformin in some inflammatory skin diseases. Moreover, novel regulatory mechanisms, including autophagy and antioxidant processes, have been suggested as promising mechanisms of action for metformin in inflammatory skin disorders.

Baseline Characteristics from UNITE: An Observational, International, Multicentre Registry to Evaluate Hidradenitis Suppurativa (Acne Inversa) in Clinical Practice

Background

Hidradenitis suppurativa (HS), also known as acne inversa, is a recurring, painful, chronic, and sometimes disfiguring inflammatory skin disease.

Objectives

Our objective was to report the baseline clinical characteristics, natural history, and associated outcomes of patients with HS from the ongoing, prospective, non-interventional UNITE registry that is collecting data regarding the natural history and associated outcomes of HS.

Methods

Patients with inflammatory HS lesions were enrolled, including adolescents (aged 12 to < 18 years) and adults (aged ≥ 18 years). None had participated in previous or current originator-adalimumab studies/registries. Patients received treatment consistent with site-specific, routine clinical practice. HS disease status was assessed by HS lesions and disease flare; treatment and outcomes data were collected at enrolment and every 6 months for ≤ 4 years.

Results

Enrolment (N = 594; 89.1% adults; 10.9% adolescents) occurred from 29 October 2013 to 29 December 2015 at 73 sites in 12 countries. At baseline, the majority were female (69.7%) and White (81.2%), had moderate-to-severe disease (Hurley stage II or III; 93.3%), and had undergone prior procedures/surgery for HS (68.7%). In total, 61.6% of adults and 49.2% of adolescents were obese; 40.2% of patients reported current tobacco use. Scarring due to lesions occurred in 91.2% of patients. The prevalence of comorbidities of interest was as follows: depression (13.3%), other psychiatric disorders (9.6%), inflammatory bowel disease (2.7%), diabetes (9.1%), and polycystic ovary syndrome (5.2%).

Conclusions

In this population from the UNITE HS registry, obesity and smoking were common, and disease burden was high, manifesting as multiple lesions, scarring, surgical history, and considerable comorbidities.

Electronic supplementary material

The online version of this article (10.1007/s40257-020-00504-4) contains supplementary material, which is available to authorized users.

IL-17 in inflammatory skin diseases psoriasis and hidradenitis suppurativa

The skin is one of the most important organs in the body, providing integrity and acting as a barrier to exclude microbes, allergens and chemicals. However, chronic skin inflammation can result when barrier function is defective and immune responses are dysregulated or misdirected against harmless or self-antigens. During the last 15 years interleukin (IL)-17 cytokines have emerged as key players in multiple inflammatory disorders, and they appear to be especially prominent in skin inflammation. IL-17 cytokines produced by T cells and other cell types potently activate keratinocytes to promote inflammation in a feed-forward loop. Given this key pathogenic role of the IL-17 pathway in autoimmune and inflammatory disease, it has been the focus of intense efforts to target therapeutically. The inflammatory effects of IL-17 can be targeted directly by blocking the cytokine or its receptor, or indirectly by blocking cytokines upstream of IL-17-producing cells. Psoriasis has been the major success story for anti-IL-17 drugs, where they have proven more effective than in other indications. Hidradenitis suppurativa (HS) is another inflammatory skin disease which, despite carrying a higher burden than psoriasis, is poorly recognized and under-diagnosed, and current treatment options are inadequate. Recently, a key role for the IL-17 pathway in the pathogenesis of HS has emerged, prompting clinical trials with a variety of IL-17 inhibitors. In this review, we discuss the roles of IL-17A, IL-17F and IL-17C in psoriasis and HS and the strategies taken to target the IL-17 pathway therapeutically.

Update on the use of dapsone in dermatology

Dapsone (4,4'-diaminodiphenylsulfone) is the only remaining sulfone used in anthropoid therapeutics and is commercially available as an oral formulation, an inhaled preparation, and a 5% or 7.5% cream. Dapsone has antimicrobial effects stemming from its sulfonamide-like ability to inhibit the synthesis of dihydrofolic acid. It also has anti-inflammatory properties such as inhibiting the production of reactive oxygen species, reducing the effect of eosinophil peroxidase on mast cells and down-regulating neutrophil-mediated inflammatory responses. This allows for its use in the treatment of a wide variety of inflammatory and infectious skin conditions. Currently in dermatology, the US Food and Drug Administration (FDA)-approved indications for dapsone are leprosy, dermatitis herpetiformis, and acne vulgaris. However, it proved itself as an adjunctive therapeutic agent to many other skin disorders. In this review, we discuss existing evidence on the mechanisms of action of dapsone, its FDA-approved indications, off-label uses, and side effects.

Hidradenitis suppurativa: Current and emerging treatments

The treatment of hidradenitis suppurativa (HS) has remained challenging because of the many knowledge gaps regarding etiology. However, recent studies into the pathogenesis of HS have enabled the investigation of newer therapies. The second article in this continuing medical education series reviews the evidence for established therapies for HS, including anti-inflammatories, antibiotics, and surgery. New and emerging therapies that specifically target cytokines involved in HS pathogenesis will be covered. The potential therapeutic roles of anticytokine therapies, including both the expanded application of existing molecules as well as the specific development of novel therapies for HS are discussed. With increased attention on HS and with numerous clinical trials currently underway, we hope that the variety of treatment options for HS will be expanded.

Biologic Treatment for Hidradenitis Suppurativa

Patients with hidradenitis suppurativa (HS) are often undertreated and there are limited efficacious therapies available for treating this population. Biologics are an emerging therapeutic modality used in the management of many inflammatory conditions including HS. Implementation of biologics is typically reserved for moderate-to-severe cases or in those cases that are refractory to treatment. Though many biologics have been trialed for use in HS, only one biologic, adalimumab, is currently US FDA (Food and Drug Administration) approved for the treatment of moderate-to-severe HS. Limitations in the use of biologics for HS include the many scoring systems utilized in research studies and the relatively few well-designed, adequately powered clinical trials.

Is There a Role for Antiandrogen Therapy for Hidradenitis Suppurativa? A Systematic Review of Published Data

BACKGROUND

Hidradenitis suppurativa/acne inversa is a disease with deep-seated chronic painful nodules, abscesses, and draining sinus tracts, which manifests on the apocrine gland-rich skin areas of the body. Observational findings demonstrate that the disease usually appears after puberty, exhibits pre-menstrual flares in women, improves in pregnancy, and worsens post-partum, which indicates a role of hormones and particularly of androgens in its pathophysiology. Because increased androgen levels in serum have not been widely reported, an end-organ androgen hypersensitivity has been postulated.

OBJECTIVE

The aim of this systematic review was to identify and present evidence for antiandrogen therapeutic options for the treatment of hidradenitis suppurativa/acne inversa.

METHODS

A literature search was conducted in different medical electronic databases using the keywords "hidradenitis", "suppurativa", "acne inversa", and "antiandrogen" on 1 December, 2018. The main therapeutic options were subsequently used as separate keywords with the disease terms in a separate search.

RESULTS

The main therapeutic options yielded were cyproterone acetate, spironolactone, finasteride, and metformin. One randomized controlled crossover trial and seven case series were identified following use of a standard extraction form for eligibility.

CONCLUSION

The existing studies do not allow a robust evidence-based recommendation for the use of antiandrogens in the treatment of hidradenitis suppurativa/acne inversa. Further randomized controlled trials are needed to define the role of hormonal treatment as an alternative or concomitant therapy together with antibiotics or biologics.

Topical, systemic and biologic therapies in hidradenitis suppurativa: pathogenic insights by examining therapeutic mechanisms

Hidradenitis suppurativa (HS) is a chronic inflammatory disease of the skin, manifesting in chronic, recurrent painful pustules, nodules, boils and purulent draining abscesses. Our current understanding of the pathogenesis of the disease is incomplete. This review aims to identify available treatment options in HS and discuss the pharmacological mechanisms through which such agents function. Identifying common pathways may inform our understanding of the pathogenesis of HS as well as identify future therapeutic targets. The pharmacological mechanisms implicated in topical therapies, antibiotic, hormonal, systemic immunomodulatory and biologic therapies for HS are discussed. Significant differences exist between agents and implicated pathways in therapy for mild and severe disease. This is an expression of the possible dichotomy in inflammatory pathways (and treatment responses) in HS. Studies involving monoclonal antibodies provide the greatest insight into what these specific mechanisms may be. Their variable levels of clinical efficacy compared with placebo bolsters the suggestion that differential inflammatory pathways may be involved in different presentations and severity of disease. Nuclear factor kappa B (NF-κB), tumor necrosis factor (TNF)-α and other innate immune mechanisms are strongly represented in treatments which are effective in mild to moderate disease in the absence of scarring or draining fistulae, however complex feed-forward mechanisms in severe disease respond to interleukin (IL)-1 inhibition but are less likely to respond to innate immune inhibition (through NF-κB or TNF-α) alone. It is unclear whether IL-17 inhibition will parallel TNF-α or IL-1 inhibition in effect, however it is plausible that small molecule targets (Janus kinase1 and phosphodiesterase 4) may provide effective new strategies for treatment of HS.

Biofilm production and antibiotic susceptibility of Staphylococcus epidermidis strains from Hidradenitis Suppurativa lesions

BACKGROUND

An aberrant interaction between commensal skin bacteria and the host skin immune system is considered important in the pathogenesis of hidradenitis suppurativa (HS).

OBJECTIVE

In this study, we investigated the antibiotic susceptibility and biofilm-forming capabilities of S. epidermidis strains isolated from HS patients.

METHODS

Skin biopsies were taken from active HS lesions such as inflammatory nodules and/or sinuses and non-involved skin from 26 patients and cultured under optimal microbiological conditions for 24 h. Planktonic growth, biofilm production, antibiotic susceptibility and biofilm eradication by clindamycin, doxycycline, rifampicin and tetracycline were tested including a laboratory control strain of S. epidermidis for reference.

RESULTS

Staphylococcus epidermidis was cultured in 16 of 26 HS patients (62%). In total 27 different S. epidermidis isolates were identified; 16 (59%) from non-involved skin and 11 (41%) from HS lesions. All bacterial strains showed planktonic growth. Twenty-four of 27 (89%) isolates were strong biofilm producers in vitro. The biofilm-forming capability varied amongst the strains from non-involved skin and lesional skin. Twenty-four strains had an intermediate to resistant antibiotic susceptibility to clindamycin (89%). Rifampicin was the most effective antibiotic at inhibiting planktonic growth and at eradication of biofilm (P < 0.05).

CONCLUSION

We observed a slight increase in S. epidermidis virulence, characterized by resistance to commonly used antibiotics, increased biofilm production and resistance to biofilm eradication. In particular, the reduced sensitivity to tetracycline and clindamycin, two standard antibiotics in the treatment of HS, is alarming. Rifampicin, also important in HS treatment, showed the greatest efficacy at eradicating the biofilm at low MIC concentrations.

The critical role of macrophages in the pathogenesis of hidradenitis suppurativa

INTRODUCTION

Hidradenitis suppurativa (HS) is a painful chronic inflammatory disease with a prevalence between 1 and 4% of general population. The pathogenesis of HS long eluded scientists, but growing evidence suggests that it is a consequence of inflammatory dysregulation.

FINDINGS

Recent studies suggest that dysregulated immune response to skin flora and overexpression of inflammatory cytokines leads to chronic skin inflammation seen in HS. Macrophages are the most numerous inflammatory cells found in HS infiltrates and release numerous pro-inflammatory cytokines such as IL-23, and IL-1β and TNF-α, exacerbating the inflammation and contributing to the pathogenesis of HS. Furthermore, in HS, there is dysregulated function of other immune players closely associated with macrophage function including: matrix metalloproteases (MMP) 2 and 9 overexpression, toll-like receptor upregulation, impaired Notch signalling, NLRP3 inflammasome upregulation, and dysregulated keratinocyte function. Lifestyle factors including obesity and smoking also contribute to macrophage dysfunction and correlate with HS incidence.

CONCLUSIONS

The overexpression of pro-inflammatory cytokines and subsequent efficacy of anti-cytokine biologic therapies highlights the importance of managing macrophage dysfunction. Future therapies should target key molecular drivers of macrophage dysfunction such as TLR2 and NLRP3 overexpression.

Approach to the Management of Patients With Hidradenitis Suppurativa: A Consensus Document

BACKGROUND

Hidradenitis suppurativa (HS) is a painful, debilitating, and poorly understood condition, which is suboptimally diagnosed, managed, and treated. Evidence supporting various treatment modalities is sparse.

OBJECTIVES

To incorporate scientific evidence and expert opinions to develop useful guidance for the evaluation and management of patients with HS.

METHODS

An expert panel of Canadian dermatologists and surgeons developed statements and recommendations based on available evidence and clinical experience. The statements and recommendations were subjected to analysis and refinement by the panel, and voting was conducted using a modified Delphi technique with a prespecified cutoff agreement of 75%.

RESULTS

Ten specific statements and recommendations were accepted by the expert panel. These were grouped into 4 domains: diagnosis and assessment, treatment and management, comorbidities and a multidisciplinary approach, and education.

CONCLUSIONS

These statements and recommendations will serve to increase awareness of HS and provide a framework for decisions involving diagnosis and management. Evidence suggests that antibacterial and anti-tumour necrosis factor therapies are effective in the treatment of HS. This is supported by the clinical experience of the authors. Further clinical research and the establishment of multidisciplinary management teams will continue to advance management of HS in Canada.

An Atypical Localized Form of Hidradenitis Suppurativa of the Jawline and Neck Mimicking Severe Cystic Acne on Presentation

Hidradenitis suppurativa (HS) is a chronic and debilitating suppurative disease primarily affecting the axillae, perineum, and inframammary regions, where apocrine sweat glands are present. However, HS can occur in atypical locations. We present an interesting case of a 40-year-old man who developed chronic painful subcutaneous nodules, deep sinus tracts, and abscesses involving the jawline and the anterior aspect of the neck as the only parts of the body affected and who responded satisfactorily to adalimumab and laser hair removal treatment. This case is relevant because it helps clinicians to remember that HS may be isolated to atypical locations, such as the anterior aspect of the neck and chin. It also supports another possible HS pathogenesis which consists of the occlusion of terminal hair follicles rather than being essentially a disorder of the apocrine glands.

Bacterial biofilm in chronic lesions of hidradenitis suppurativa

BACKGROUND

Chronic nonhealing or recurrent inflammatory lesions, reminiscent of infection but recalcitrant to antibiotic therapy, generally characterize biofilm-driven diseases. Chronic lesions of hidradenitis suppurativa (HS) exhibit several characteristics, which are compatible with well-known biofilm infections.

OBJECTIVES

To determine and quantify the potential presence of bacterial aggregates in chronic HS lesions.

METHODS

In 42 consecutive patients with HS suffering from chronic lesions, biopsies were obtained from lesional as well as from perilesional skin. Samples were investigated using peptide nucleic acid-fluorescence in situ hybridization in combination with confocal laser scanning microscopy. In addition, corresponding histopathological analysis on haematoxylin and eosin slides was performed.

RESULTS

Biofilms were seen in 67% of the samples of chronic lesions and in 75% of the perilesional samples. The mean diameter of aggregates in lesional skin was significantly greater than in perilesional skin (P = 0·01). Large biofilms (aggregates > 50 μm in diameter) were found in 42% of lesional samples and in only 5% of the perilesional samples (P = 0·009). The majority of the large biofilms were situated in sinus tracts (63%) or in the infundibulum (37%). The majority of the sinus tract samples (73%) contained active bacterial cells, which were associated with inflammation.

CONCLUSIONS

This study suggests that biofilm formation is associated with inflammation of chronic HS lesions. The aggregates most likely occur as a secondary event, possibly due to predisposing local anatomical changes such as sinus tracts (tunnels), keratinous detritus and dilated hair follicles.

The Clinical Pattern of Axillary Hidradenitis Suppurativa among Saudi Arabians: Mode of Presentation and Treatment Challenges

Background:

Hidradenitis suppurativa is a chronic follicular occlusive disease affecting the folliculopilosebaceous unit. The clinical course is variable, ranging from mild to severe cases. Definitive evidence-based guidelines for the management are lacking. In addition, the multifaceted clinical features and the unpredictable course of the disease make a uniform approach to treatment impractical. As a result, there are multiple therapeutic approaches. Therefore, in this study, we aim to analyze the results of management of axillary hidradenitis suppurativa among the local community in Saudi Arabia.

Materials and Methods:

A retrospective cohort database analysis of 1369 patients diagnosed and treated for axillary hidradenitis suppurativa between January 2004 and December 2013 was done. Seven hundred and forty-one (54.12%) were females and 628 (45.87%) were males. All patients with Stage I disease favored the conservative method while all patients with Stage II chose the surgical approach.

Results:

The mean age was 25.5 years. Nine hundred and seventy-four (71.15%) patients were treated conservatively; the mean healing time was 5.5 weeks. Three hundred and ninety-five (28.85%) patients were treated surgically. One hundred and fourteen (28.9%) had incision and drainage, 281 (71.1%) had complete excision; all wounds eventually healed without significant scarring. The recurrence rate was 12.5% (122 patients) in the conservative method group and zero (0%) in the surgical method group.

Conclusions:

Hidradenitis suppurativa remains a challenging clinical condition for patients and physicians. Further studies need to focus not only on the etiology of this disease but also on the optimal treatment regimen. Public awareness programs are necessary to avoid late presentation and complications.