Sean Klepper M.D.
Artur Zembowicz M.D....
- Autosomal dominant familial and sporadic forms
- Large scaly plaques with islands of sparing, most often on the trunk
- Hyperkeratosis of the palms and soles and nail dystrophy may occur.
- Hyperkeratosis with horizontally and vertically alternating foci of parakeratosis (described as a "checkerboard" pattern)
- Mounds of parakeratosis at the edges of follicular ostia ("shoulder parakeratosis")
- Keratotic plugging of the follicular ostia
- Irregular to psoriasiform acanthosis with hypergranulosis and occasionally acantholysis
- Mild superficial perivascular lymphocytic infiltrate