These authors contributed equally to the text.

No abstract

The term 'sclerosing diseases of the skin' comprises specific dermatological entities which have fibrotic changes of the skin in common. These diseases mostly manifest in different clinical subtypes according to cutaneous and extracutaneous involvement and can sometimes be difficult to distinguish from each other. The present guideline focuses on characteristic clinical and histopathological features, diagnostic scores and the serum autoantibodies most useful for differential diagnosis. In addition, current strategies in the first- and advanced-line therapy of sclerosing skin diseases are addressed in detail. Part 2 of this guideline provides clinicians with an overview of the diagnosis and treatment of scleromyxedema, scleredema (of Buschke) and nephrogenic systemic sclerosis (nephrogenic fibrosing dermopathy).

Hydroquinone and other cutaneous depigmenting agents are widely used by dermatologists to treat pigmentary disorders. On 29 August 2006, the US Food and Drug Administration (FDA) published a monograph in the US Federal Register proposing to ban all hydroquinone products that have not been approved via a New Drug Application process. Reports in the scientific literature on the occurrence of exogenous ochronosis, in relation to the use of hydroquinone, was one of the concerns expressed by the FDA in relation to this agent. However, a review of the English-language scientific literature reveals that most of the reported cases of hydroquinone-induced exogenous ochronosis occurs in Africa, where the cultural practice of skin bleaching is highly prevalent. Skin bleaching is the practice of applying hydroquinone and/or other depigmenting agents to specific or widespread areas of the body, the primary function being to lighten normally dark skin. This practice typically occurs in men and women with Fitzpatrick skin phototypes IV to VI. It is a dangerous practice associated with a diverse range of side-effects, including mercury poisoning. Thus, this current discussion within the dermatological community on the safety of hydroquinone provides a unique opportunity to raise awareness about skin bleaching.

Objective. Hypocomplementemic urticarial vasculitis (HUV) is an uncommon vasculitis of unknown etiology that is rarely described in the literature. We undertook this study to analyze the clinical spectrum and the therapeutic management of patients with HUV.Methods. We conducted a French nationwide retrospective study that included 57 patients with chronic urticaria, histologic leukocytoclastic vasculitis, and hypocomplementemia. We assessed clinical and laboratory data and evaluated the patients' cutaneous and immunologic responses to therapy. We evaluated