Histopathology of Psoriasis

1. Parakeratosis
2. Stratum granulosum, which is normally found under stratum corneum, is thinned or lost.
3. The spinal layer over the papillae is thinned.
4. Papillae are elongated and the upper parts are dilated (Papillomatosis)
5. Interpapiller regions are regularly extended and lower parts are thickened.