Doctor's Notes on Nail Psoriasis
Psoriasis is a common, chronic skin condition that usually manifests as patches of raised, red skin with silvery scales. These skin changes in psoriasis usually occur on the elbows, scalp, knees, and trunk. Psoriasis can also affect the fingernails and toenails. The cause of psoriasis is not well understood, although it is known to run in families. Nail psoriasis most likely is caused by a combination of genetic (inherited), immunologic, and environmental factors.
Signs and symptoms of nail psoriasis include thickened nails, pitting, ridges in the nails, nails loosening from the nail bed, and irregular contour of the nails. Other associated symptoms can include crumbling of the nails, white areas on the nail plate, furrows known as Beau's lines that run across the nails, and thickened skin beneath the nail bed.
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Psoriasis causes the top layer of skin cells to become inflamed and grow too quickly and flake off.
See AnswerREFERENCE:
Kasper, D.L., et al., eds. Harrison's Principles of Internal Medicine, 19th Ed. United States: McGraw-Hill Education, 2015.