Subcorneal Pustular Dermatosis Exhibiting a High Serum TARC/CCL17 Level.

Subcorneal pustular dermatosis (SPD) is a rare, relapsing, symmetric sterile pustular eruption that dominantly involves flexural areas. It is considered one form of neutrophilic dermatoses, which are associated with interleukin (IL)-17-producing T helper (Th) 17 cells that induce IL-8 production. We have previously reported that Th17 might be involved in the pathomechanism of Th2-dominant atopic dermatitis [Koga et al.: J Invest Dermatol 2008;128:2625-2630]. On the other hand, it has been a debate whether Th2 is involved in the etiology of neutrophilic dermatoses. Herein, we report a case of SPD that exhibited a high serum thymus and activation-regulated chemokine/chemokine (C-C motif) ligand 17 level, thereby raising the possibility of a Th2 association in its pathogenesis. Although it was limited to a single observation, our case raised the possibility that SPD may possess Th2 properties.