Abstract
In some patients, psoriasis appears refractory to many treatments, particularly when the disease is confined to some specific body regions. In this respect, palmoplantar psoriasis and palmoplantar pustulosis are possibly related conditions in their immunopathomechanisms involving Il-12, IL-23, and Th17. Nail psoriasis and scalp psoriasis are two other particular psoriasis manifestations. Accordingly, ustekinumab was tested in a few of these patients. The present paper is limited to peer-reviewed case reports. Data were not supported by bioinstrumental assessments and controlled trials. Overall, they are indicative of potential efficacy. The cost-effectiveness and the risk-benefit assessments merit further investigations.