The spectrum of nail involvement in palmoplantar pustulosis.

Abnormalities of the nail are not a well recognized feature of palmoplantar pustulosis (PPP). However, in a group of 50 patients with PPP, we found nail dystrophy in 15 (30%). The most frequent pattern was subungual pustulation, present in 10 patients, and progressing to nail destruction in two. Onycholysis and pitting of the nail were present in a few patients. In contrast to psoriasis vulgaris, the rate of linear nail growth in PPP was no greater than in matched normal controls. This is another clinical feature of PPP that separates it from psoriasis vulgaris.