Bullous delayed pressure urticaria responding to omalizumab

Abstract

Delayed pressure urticaria (DPU) has been reported to occur in up to 37% of patients with chronic spontaneous urticaria (CSU), but frequently goes unrecognized on account of its delayed onset (1). Lesions are typically painful and persist for up to 72 h. DPU has been shown to cause significantly greater impairment in quality of life than other forms of urticaria (2). The pathogenesis is unclear, but, unlike CSU, eosinophils are thought to play an important pathophysiological role. DPU is generally unresponsive to high-dose antihistamines, and medicaments such as dapsone and corticosteroids are neither consistently effective nor, in the latter case, suited for long-term therapy. While there are reports of omalizumab (anti-IgE) having a favourable effect on DPU (3, 4) a recent case responded neither to omalizumab nor to tumour necrosis factor (TNF)-α blockade with adalimumab (5). With regard to TNF-α blockade, a case of DPU responding to etanercept without relapse on switching to infliximab has been published (6). In contrast to DPU, bullous DPU is an extremely rare entity, with only 2 cases published to date (7-9). We describe here a rare case of bullous DPU with complete response to omalizumab treatment.