Estrías generalizadas secundarias a tratamiento tópico con clobetasol y minoxidil en un paciente con psoriasis

The hair follicle-psoriasis axis: Shared regulatory mechanisms and therapeutic targets

It has long been known that there is a special affinity of psoriasis for the scalp: Here, it occurs most frequently, lesions terminate sharply in frontal skin beyond the hair line and are difficult to treat. Yet, surprisingly, scalp psoriasis only rarely causes alopecia, even though the pilosebaceous unit clearly is affected. Here, we systematically explore the peculiar, insufficiently investigated connection between psoriasis and growing (anagen) terminal scalp hair follicles (HFs), with emphasis on shared regulatory mechanism and therapeutic targets. Interestingly, several drugs and stressors that can trigger/aggravate psoriasis can inhibit hair growth (e.g. beta-blockers, chloroquine, carbamazepine, interferon-alpha, perceived stress). Instead, several anti-psoriatic agents can stimulate hair growth (e.g. cyclosporine, glucocorticoids, dithranol, UV irradiation), while skin/HF trauma (Köbner phenomenon/depilation) favours the development of psoriatic lesions and induces anagen in "quiescent" (telogen) HFs. On this basis, we propose two interconnected working models: (a) the existence of a bidirectional "hair follicle-psoriasis axis," along which keratinocytes of anagen scalp HFs secrete signals that favour the development and maintenance of psoriatic scalp lesions and respond to signals from these lesions, and (b) that anagen induction and psoriatic lesions share molecular "switch-on" mechanisms, which invite pharmacological targeting, once identified. Therefore, we advocate a novel, cross-fertilizing and integrative approach to psoriasis and hair research that systematically characterizes the "HF-psoriasis axis," focused on identification and therapeutic targeting of selected, shared signalling pathways in the future management of both, psoriasis and hair growth disorders.

Skin atrophy caused by topical glucocorticoids is less common in patients with atopic dermatitis than in those with psoriasis

Although the long-term use of topical glucocorticoids (TGC) may induce skin atrophy including striae distensae (SD), patients with atopic dermatitis (AD) appear to have lesser degree of skin atrophy than those with psoriasis (PSO). Periostin, encoded by POSTN, is involved in tissue remodelling processes of chronic AD lesions. This study was designed to investigate the difference in the occurrence of skin atrophy in patients with AD or PSO when treated with TGC and to elucidate the association between skin atrophy and periostin. Big data analysis using Korean Health Claims Database was performed to determine the prevalence of SD in AD and PSO patients. Blood and skin eosinophils count and dermal fibrosis between AD and PSO patients were compared, and immunohistochemistry for periostin and mRNA sequencing in the dermis were performed. Animal experiments using AD and PSO murine model were conducted. Big data analysis revealed that patients with AD have significantly lesser degree of SD than patients with PSO. The ratio of the dermal fibrous tissues and eosinophil counts were significantly higher in AD patients. In AD skin, periostin was more widely distributed in the entire dermis and POSTN mRNAs were significantly upregulated. Dermal thickness and fibrosis were significantly higher in AD mice even after TGC treatment. A significant positive correlation was observed between dermal fibrosis and tissue eosinophil counts. Lesser skin atrophy in AD patients even after long-term TGC application could be resulted from skin fibrosis caused by increased tissue eosinophils and periostin deposition.

Compounded topical preparations in plaque psoriasis: Still a place for it in 2018?

Compounded topical preparations (CTP) were used to treat psoriasis until the last century and have disappeared from guidelines. The present authors report two severe psoriasis patients who were treated with CTP. A man had psoriasis with a PASI of 23 and a body surface area (BSA) of 43%. He had been using daily for several weeks a CTP including minoxidil, clobetasol propionate and hydroxyprogesterone formulated in an alcohol based vehicle. A woman suffered from psoriasis with an annular inflammatory pattern and a central healing. The PASI was 20 and the BSA was 30%. She had been using a CTP daily for 4 months including resorcinol, salicylic acid, 0.05% tretinoin cream, bethamethasone dipropionate cream. Until the 1970s, the dermatological textbooks recommended to treat severe psoriasis with CTP. Nowadays, CTP are considered outdated because of the large therapeutic armamentarium. The stability and benefit risks of the CTP used here were not documented. The use of CTP in psoriasis should be regulated and must be evidence based. Strict protocol and stability evaluation for preparations must be confirmed prior to compounding.