The pustule in palmoplantar psoriasis: transformed vesicle or mature microabscess? A three-dimensional study

Psoriasis on the palms and soles is characterized by pustules, vesicles and hyperkeratotic plaques. Several studies have postulated that the pustules and vesicles are round or egg-shaped. This three-dimensional study reveals that neither pustules nor vesicles have a regular spherical morphology. The vesicles are located in the upper and middle layers of the epidermis and may exhibit dumb-bell- or banana-shaped lumina. The pustules consist of different compartments combining characteristics of a dyshidrotic vesicle with those of a microabscess of Munro.