[Indications and modes of use for interleukin (IL)-1 antagonists in inflammatory dermatosis: a new therapeutic approach to immune-mediated inflammatory diseases].

BACKGROUND: IL-1 antagonists are used in the treatment of patients with rheumatoid arthritis and cryopyrinopathies. As yet anecdotal observations suggest that they may allow effective treatment of patients with different types of inflammatory skin disease. This review focuses on our current knowledge of the use of IL-1 antagonists in dermatology.

PATIENTS AND METHODS: A Medline search was performed combining the keywords: "anakinra; canakinumab; rilonacept" AND "skin; neutrophilic dermatoses; Sweet syndrome; pyoderma gangrenosum; hidradenitis suppurativa; Schnitzler syndrome; Still disease". The precise dermatological phenotype of patients with IL-1 antagonist-responsive auto-inflammatory disorders was analysed in order to compare it to related complex disorders.

RESULTS: Double-blind randomized controlled trials have demonstrated the efficacy of these treatments in cryopyrinopathies with dermatological involvement including chronic infantile neurological cutaneous and articular (CINCA) syndrome, Muckle-Wells syndrome and familial cold urticaria. Anakinra is the only treatment for Schnitzler syndrome that is almost constantly efficacious, even in refractory disease, as attested by numerous case reports. It is also efficacious in the treatment of patients with adult-onset Still disease and systemic juvenile arthritis. Neutrophilic dermatoses constitute the cutaneous hallmark of IL-1-responsive auto-inflammatory disorders, and neutrophilic dermatoses could thus form an indication for this treatment. However, to date, only 9 reports have been published showing efficiency in patients with Sweet syndrome, in one case of neutrophilic panniculitis, and in two cases of pustular psoriasis. Anakinra appears less efficacious in patients with pyoderma gangrenosum.

CONCLUSION: IL-1 antagonists are a first-line treatment in patients with Schnitzler syndrome and cryopyrinopathies. They could become important alternatives in patients with acute and febrile neutrophilic dermatoses either unresponsive to or with contraindications to conventional treatments, but this requires confirmation by further clinical trials.