Rosacea is a common chronic inflammatory skin disorder that mainly affects the central face. It is primarily characterized by recurrent episodes of flushing, persistent erythema, inflammatory papules, telangiectasias, phymatous changes, and ocular symptoms. Its pathogenesis is complex and still not completely understood. It encompasses innate and adaptive immune system dysregulation, neurovascular dysfunction, and genetic and environmental factors. To date, four subtypes of rosacea have been identified, based on the predominant clinical features: erythemato-teleangiectatic, papulopustular, pyhomatous, and ocular rosacea. New insights into this condition have led to several pharmacological treatments, including topical medications, spanning from the conventional azelaic acid, metronidazole, benzoyl peroxide, clindamycin, and erythromycin to new ones including not only brimonidine, oxymetazoline, ivermectine, and minocycline but also systemic drugs such as oral antibiotics, isotretinoin, non-selective β-blockers or α2-adrenergic agonists, and laser- or light-based therapies, together with new therapeutic approaches. The aim of this study was to review the current literature on the pathophysiology of rosacea and to provide an overview of therapeutic approaches that specifically address each clinical subtype.

Hidradenitis suppurativa (HS) is a chronic and debilitating inflammatory skin disease that often exhibits heterogeneity in its clinical presentation, especially in the context of its rare syndromic forms. The pathogenesis of HS results from a complex interplay of genetic predisposition, innate and adaptive immunity dysregulation, smoking, obesity and environmental factors. In the early phase of the disease, the innate immune system is hyperactivated, contributing to tissue damage and triggering the activation and amplification of the adaptive immune response, which plays a pivotal role in the chronic stages of the disease. Recent studies focused on elucidating the importance of innate immunity impairment and autoinflammation in HS and increasing evidence has emerged on the occurrence of the disease in the context of well-known monogenic and polygenic autoinflammatory syndromes (AIDs). This review provides a comprehensive examination of the current scientific background supporting the contribution of autoinflammation to HS etiology, including genetic data, molecular studies and clinical evidence, as well as the association between HS and AIDs. However, further research is needed to shed light on the pathogenic mechanism of this challenging condition and to identify potential perspectives for future therapeutic approaches.

Lichen planus (LP) is a chronic inflammatory disorder affecting approximately 1% of the population. It presents with a wide range of clinical manifestations, mainly involving the skin, mucosal surfaces, and skin appendages, and is often characterized by a relapsing course and variable response to treatment. Although several therapeutic strategies are available, many are off-label and show limited efficacy in resistant forms. Increasing evidence points to the central role of the JAK/STAT signaling pathway in the immunopathogenesis of LP, with cytokines such as interferon-gamma and interleukin-21 playing key roles in sustaining chronic inflammation. Based on this rationale, Janus kinase (JAK) inhibitors have recently been proposed as potential therapeutic agents in LP. This review explores the biological basis for their use and systematically summarizes the existing clinical evidence on the use of JAK inhibitors in cutaneous, mucosal, appendageal, and nail variants of LP. The preliminary data suggests favorable outcomes in many patients with difficult-to-treat disease, with an acceptable safety profile. Further prospective trials are needed to establish their definitive role in the management of LP.

Introduction: Soon after birth, the clinical differential diagnosis between sebaceous of Jadassohn (NSJ), congenital triangular alopecia (CTA) and aplasia cutis congenita (ACC) may be challenging. A certain overlap of standard dermoscopic features can occur, especially in atypical cases, depending on scalp skin morphology and maturation age. The recently developed line-field confocal optical coherence tomography (LC-OCT) can provide morphological skin details with cellular resolution trough a rapid non-invasive examination. Objectives: To assess the LC-OCT features of 6 cases of congenital alopecia of different aetiologies, with both typical and atypical clinical appearance. Methods: A non-invasive imaging examination combining standard dermoscopy, high-resolution videodermoscopy (HRVD) and LC-OCT was realized in 7 babies presenting for congenital alopecia with overlapping features, aged between 5 months and 5 years. Results: Based on the specific LC-OCT features, and supported by HRVD features, a diagnosis of nevus sebaceous of Jadassohn (NSJ), congenital triangular alopecia (CTA) and aplasia cutis congenita (ACC) were made in 4, 2 and 1 case, respectively. Conclusions: The combined LC-OCT plus HRVD non-invasive imaging bring the advantage to have a real time diagnosis, to set the proper management and allows to avoid a skin biopsy in the perinatal age/first years of life at delicate skin site.