Amicrobial pustulosis of the folds and palmoplantar pustulosis simultaneously induced by different tumor necrosis factor-α inhibitors: Demonstration of a shared pathophysiology

Abstract

Amicrobial pustulosis of the folds (APF) and palmoplantar pustulosis (PPP) are 2 rare autoinflammatory neutrophilic dermatoses. Many studies report PPP triggered by treatment of inflammatory bowel disease (IBD) with tumor necrosis factor-α (TNF-α) blockers.1, 2 APF is much rarer and predominantly affects young women with autoimmune conditions.3 Both conditions share histologic features of superficial spongiform pustulation associated with perivascular neutrophilic infiltration, without evidence of infection or vasculitis.3 The clinical differentiation of these disorders is largely based on anatomic location. APF commonly occurs on cutaneous folds of the skin, the scalp, and the periorificial areas of the head. PPP, as the name suggests, primarily occurs on the palms and soles. These 2 conditions are currently considered separate entities. TNF-α blockers are used in a variety of diseases, notably IBD, psoriasis, and rheumatoid arthritis. Pustular reactions, whether PPP or APF, occur in less than 1% of patients treated with TNF-α inhibitors.4 We report a novel case of APF and PPP occurring and relapsing together in a patient after treatment with adalimumab and certolizumab.