Neutrophilic urticarial dermatosis: a variant of neutrophilic urticaria strongly associated with systemic disease. Report of 9 new cases and review of the literature.

We conducted the current study to define within the spectrum of the neutrophilic dermatoses a group of patients with an urticarial rash clinically and a neutrophilic dermatosis histopathologically. We reviewed the literature on neutrophilic urticaria and we report here a series of patients with this unique presentation. We reviewed all cutaneous biopsies submitted to our department between 2000 and 2006 in which histopathologic evaluation was compatible with this entity. We then retrieved the patient medical records and obtained information about follow-up and associated diseases. This allowed us to identify 9 patients with an urticarial eruption that was characterized histopathologically by a perivascular and interstitial neutrophilic infiltrate with intense leukocytoclasia but without vasculitis and without dermal edema. Four patients also had small foci of necrobiotic collagen bundles. The eruption consisted of pale, flat or only slightly raised, nonpruritic macules, papules, or plaques. Elementary lesions resolved within 24 hours. Purpura, angioedema, and facial swelling were not seen, but dermographism was present in 1 patient. Six patients had fever, 7 had polyarthritis, and 6 had leukocytosis. Seven patients had associated systemic diseases: adult-onset Still disease (3 patients), systemic lupus erythematosus (3 patients), and Schnitzler syndrome (1 patient).A similar rash has been reported previously in the literature, mostly in patients with systemic inflammatory diseases, but the majority of patients reported under the undefined designation of "neutrophilic urticaria" did have a different clinicopathologic presentation. Thus, we suggest naming this eruption "neutrophilic urticarial dermatosis," to emphasize that this entity expands the broad group of cutaneous manifestations of neutrophilic aseptic disease. This entity bears important medical significance as it is strongly indicative of an associated systemic disease, mainly Schnitzler syndrome, adult-onset Still disease, lupus erythematosus, and the hereditary autoinflammatory fever syndromes.