Systemic Antibiotic Therapy in Hidradenitis Suppurativa: A Review on Treatment Landscape and Current Issues

Topical and Systemic Retinoids in the Management of Hidradenitis Suppurativa: A Comprehensive Literature Review

Hidradenitis suppurativa (HS) is a debilitating chronic skin disorder characterized by painful inflammatory nodules, abscesses and sinus tracts involving intertriginous areas and has an adverse impact on patient quality of life. Over the past decade, the therapeutic options of HS have increased significantly to comprise multiple modalities, including topical medication, systemic therapies (mainly antibiotics, retinoids, and biologics), surgical approaches, and lifestyle modifications. Biologics alone or in combination with surgery remain the treatment of choice for moderate to severe disease. However, non-biologic therapies (including retinoids) may be used as monotherapy for mild disease and in combination with biologics and surgical treatment in moderate to severe disease. Retinoids, specifically isotretinoin, acitretin, and alitretinoin, are historically used in the management of HS, supported by anecdotal evidence and with variable treatment response. Although the current American and European guidelines offer different recommendations on the use of retinoids in HS, retinoids remain a valuable ally in HS management. This review provides a comprehensive analysis of the current scientific literature on retinoid therapy (topical and systemic) in HS, highlighting disparities in mechanisms of action, efficacy, and safety to clarify their role in HS treatment.

Rethinking Hidradenitis Suppurativa Management: Insights into Bacterial Interactions and Treatment Evolution

Hidradenitis suppurativa (HS), or acne inversa, is a chronic inflammatory dermatological condition characterized by painful and recurrent nodules and purulent abscesses. HS can have a devastating impact on the quality of life of patients. This condition is commonly localized to the axilla, groin, perineal, and inframammary regions, and can develop fistulas and sinus tracts over time. Its pathogenesis remains elusive and is best characterized at the moment as multi-factorial. Additionally, questions remain about the role of cutaneous dysbiosis as a primary HS trigger or as a secondary perturbation due to HS inflammation. This article features works in relation to HS and its interplay with bacterial microflora. We address current treatment approaches and their impact on HS-related bacteria, as well as areas of therapeutic innovation. In the future, disease-modifying or remittive therapy will likely combine an advanced/targeted anti-inflammatory approach with one that effectively modulates cutaneous and deep tissue dysbiosis.

Detection of native, activated Notch receptors in normal human apocrine-bearing skin and in hidradenitis suppurativa

Notch signalling has generated considerable interest as a pathogenetic factor and a drug target in a range of human diseases. The gamma-secretase complex is crucial in the activation of Notch receptors by cleaving the intracellular domain allowing nuclear translocation. In recent years several mutations in gamma-secretase components have been discovered in patients with familial hidradenitis suppurativa (HS). This has led to hypotheses that impaired Notch signalling could be an important driver for HS in general, not only in the monogenic variants. However, no study has examined in situ Notch activation per se in HS, and some reports with conflicting results have instead been based on expression of Notch receptors or indirect measures of Notch target gene expression. In this study we established immunostaining protocols to identify native, activated Notch receptors in human skin tissue. The ability to detect changes in Notch activation was confirmed with an ex vivo skin organ model in which signal was reduced or obliterated in tissue exposed to a gamma-secretase inhibitor. Using these methods on skin biopsies from healthy volunteers and a general HS cohort we demonstrated for the first time the distribution of active Notch signalling in human apocrine-bearing skin. Quantification of activated NOTCH1 & NOTCH2 revealed similar levels in non-lesional and peri-lesional HS to that of healthy controls, thus ruling out a general defect in Notch activation in HS patients. We did find a variable but significant reduction of activated Notch in epidermis of lesional HS with a distribution that appeared related to the extent of surrounding tissue inflammation.

Transcriptomic Analysis of Hidradenitis Suppurativa: A Unique Molecular Signature with Broad Immune Activation

Hidradenitis suppurativa is a chronic inflammatory skin disease with limited treatment options. The poorly understood pathogenesis hinders the development of effective treatments; therefore, a pressing need exists to further elucidate the molecular mechanisms in hidradenitis suppurativa. This study investigated the underlying inflammatory pathways and cell types in hidradenitis suppurativa using transcriptomic approaches with RNA sequencing of lesional and non-lesional skin biopsies from hidradenitis suppurativa, which was jointly analyzed with previously published transcriptomic data from atopic dermatitis and psoriasis patients. The differential expression and pathway enrichment analyses demonstrated the activation of multiple inflammatory processes, including the innate and adaptive immune systems, implicated in the hidradenitis suppurativa pathogenesis. In agreement, hidradenitis suppurativa exhibited a unique and heterogeneous cell type signature involving lymphoid and myeloid cells such as B cells and macrophages. Furthermore, hidradenitis suppurativa displayed increased expression of TH1/2/17 signatures with no predominant TH signatures unlike psoriasis (TH1/17) and atopic dermatitis (TH2). In summary, our study provides molecular insights into the pathomechanisms in hidradenitis suppurativa, revealing a strong and widespread immune activation, which may benefit from treatment strategies offering a broad immunomodulation of various key inflammatory pathways. Our data not only corroborate previously reported findings but also enhance our understanding of the immune dysregulation in hidradenitis suppurativa, uncovering novel and potential therapeutic targets.

Challenges in the Management of Perianal Hidradenitis Suppurativa in an African American Male: A Case Report

Hidradenitis suppurativa (HS), more commonly known as acne inversa, occurs due to chronic inflammation of the body's apocrine glands, most commonly affecting areas of the body where there is prolonged skin-on-skin friction. HS affects approximately 4% of the United States population, most commonly women in their second or third decade of life, especially those of African American ethnicity. HS presents as tender subcutaneous nodules which often rupture, leading to the formation of painful dermal abscesses which undergo fibrosis and lead to the formation of extensive sinus tracts, a phenomenon known as "tunneling". HS is staged clinically using the Hurley staging system, where the stage determines what treatment modalities are used. These modalities can include medical management such as antibiotics, or biologics such as tumor necrosis factor (TNF)-alpha inhibitors like adalimumab, as well as surgical options including incision with or without drainage. Due to the similar presentation of HS with other conditions, this disease is commonly misdiagnosed, often leading to delayed treatment initiation and worse outcomes for patients. Presented is a case report of a 30-year-old African American male with perianal HS and the potential long-term complications and challenges of management of this disease.

Clinical and Ultrasonographic Characterization of Hidradenitis Suppurativa in Female Patients: Impact of Early Recognition of the Disease

Hidradenitis suppurativa (HS) is considered a post-pubertal disease; however, earlier onset is not infrequent. The burden of HS on the female population is very relevant, and early identification might reduce the quality of life impairment and improve the therapeutic approach. In this study, we investigated clinical biomarkers of HS that could impact the management of patients affected by HS. Female patients affected by stable HS were prospectively included in this study. Anamnestic data, clinical and ultrasonographic features were collected and analyzed. Overall, 53 patients were included in this study. The median age of onset was 19 (IQR: 14-25). Early onset was reported by 22/53 patients (median age of onset: 14; IQR: 11-16). Four patients had pre-menstruation occurrence. Early-onset patients had an earlier first-menstrual-cycle age and more frequent genital localization of HS, and were more often treated with biologics. Patients with early-onset-HS and genital localization had more severe disease with a higher number of areas affected, Hurley, and IHS4 scores. Genital involvement might be prevalent in patients with early-onset HS, leading to a worse impact on the global severity of the disease and tailored treatment protocols, including multidisciplinary approaches, in order to improve the early recognition of hidden lesions.