Treatment of Palmoplantar Pustulosis with the Combination of Ustekinumab and Apremilast: A Case Report

Palmoplantar pustulosis (PPP) is characterized by sterile pustules on the palms and soles along with hyperkeratosis, scaling and fissuring [1]. PPP can present by itself, or along with plaque psoriasis where it is considered Palmoplantar pustular psoriasis (PPPP) [1,2]. Genetic studies indicate that PPP may not be related to psoriasis, possibly accounting for their different responses to certain treatments, namely TNF-α antagonists [3]. Gene expression microarray analysis has shown that PPP and PPPP are not distinct clinical entities and differ from psoriasis based on increased expression of GPRIN1 and ADAM23 at the gene and protein level [2]. PPP is more common in middle-aged women, diabetics and smokers [1]. PPP may also be associated with thyroid dysfunction [4] and is part of the of clinical SAPHO syndrome, where it may occur with one or more of the following: synovitis, acne, pustulosis, hyperostosis and osteitis [5].