Summary Lichen planus (LP) is a chronic lichenoid inflammatory disorder of the skin, mucosa and of the appendages. LP is classically characterized by the presence of a rich infiltration of inflammatory T cells, which migrate in the upper part of the dermis, arranged in a band‐like pattern. Different sub types of the disease have been so far described. Albeit LP is clinically well defined, the disease still represents a therapeutic enigma. Especially with regard to mucosal or scalp affecting LP types, which often present a recalcitrant and treatment unresponsive course, efficacious therapeutic options are still lacking. Thus, LP represents a disease with a high psychosocial burden. Yet, development in the deciphering of LP pathogenesis reveals possible new druggable targets, thus paving the way for future therapeutic options. In this clinical guide, we summarize the current clinical knowledge and therapeutic standards and discuss the future perspective for the management of LP.

Spondyloarthritides (SpA) like psoriatic arthritis, axial spondyloarthritis/ankylosing spondylitis, reactive arthritis and inflammatory bowel disease (IBD)-associated SpA can present with characteristic skin manifestations. These SpA-associated skin disorders may precede joint involvement, reflect a loss of efficacy of a current systemic treatment or can even be treatment associated. Cutaneous manifestations in SpA not only add additional morbidity with physical impact but also impose a psychosocial burden on affected patients. Psoriasis (PsO) – the main skin disease in SpA – has a variety of clinical presentations, including plaque-type PsO, inverse PsO, guttate PsO, erythrodermic PsO, nail PsO and pustular types. SpA associated with IBD presents with neutrophilic and granulomatous skin disorders, including pyoderma gangrenosum, hidradenitis suppurativa and cutaneous Crohn’s disease. Reactive arthritides has a favourable prognosis and may feature keratoderma blenorrhagicum or balanitis circinatum as typical skin manifestations. Immunologically, SpA-associated skin diseases share interleukin (IL)-17 and IL-23 dysregulation but show distinctive genetic and immunological profiles. Therefore, they vary in their treatment responses to targeted therapies with biologicals or small molecules. In this review, we highlight the clinical presentation of skin manifestations in SpA and discuss therapeutic approaches in this interdisciplinary field.

Zusammenfassung Lichen planus (LP) ist eine chronisch lichenoide Erkrankung der Haut, der Schleimhäute und der Adnexe. Klassischerweise ist LP durch ein dichtes bandförmiges Infiltrat von T‐Zellen im oberen Teil der Dermis gekennzeichnet. Bisher wurden verschiedene Subtypen der Erkrankung beschrieben. Obwohl LP klinisch gut definiert ist, stellt die Erkrankung immer noch eine therapeutische Herausforderung dar. Insbesondere für LP‐Typen an Schleimhaut oder Kopfhaut, die oft rezidivieren und nicht auf Behandlungen ansprechenden, fehlen nach wie vor wirksame Therapien. LP bedingt eine sehr hohe psychosoziale Belastung bei den Betroffenen. Neue Erkenntnisse zur LP‐Pathogenese zeigen mögliche Angriffspunkte für Medikamente auf und ebnen so den Weg für künftige Therapien. In diesem klinischen Leitfaden fassen wir das aktuelle Wissen und die Therapiestandards zusammen und diskutieren die Zukunftsperspektive der Behandlung des LP.

Objective. Women are more frequently affected by connective tissue diseases like systemic sclerosis (SSc). Therefore, few studies exist on male-specific complaints. This study aimed to investigate the prevalence and associated factors of erectile dysfunction (ED) in SSc compared with other connective tissue diseases (CTD) and healthy controls. Methods. 64 patients were analysed and compared with 123 age-matched HC. The 15-item International Index for Erectile Function (IIEF) questionnaire was used to assess sexual function. The prevalence of depression was quantified by using the validated Beck Depression Inventory (BDI). Results. Mean age was 52.3 years (SD 10.75) for SSc, 52.9 years (SD 11.01) for patients with other CTD and 52.6 (SD 12.37) for HC. Mean IIEF-15 score was 13.6 for SSc, 11.7 for other CTD and 23.6 for HC. ED was significantly more frequent in patients with SSc (55.0%) and other CTD (54.4%) than in HC (12.7%) (p<0.001) and correlated with diseases severity. The mean BDI score was 10.8 for SSc/CTD and 5.4 for HC (p<0.001). With 36.6%, SSc patients suffered more often from a depression than patients with other CTD (17.4%) and HC (6.3%). We found a significant correlation between the IIEF-15 and depression classified by p<0.001). Conclusion. This is the first study to show increased prevalence of ED, especially severe ED, in men with SSc compared to other CTD and age-matched HC. Physicians should be aware of this influence on sexual health and its correlation to depression and disease severity.