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Facts about the skin from DermNet New Zealand Trust. Topic index: A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

Nail psoriasis

What is nail psoriasis?

Psoriatic nail dystrophy mainly occurs in patients whom also suffer from psoriasis of the skin. Less than 5% of patients have solely psoriasis of the nails. It is commonly (53-86%) seen in patients with psoriatic arthritis especially when the arthritis affects the fingers and toes.

Nails in psoriasis Nails in psoriasis Nails in psoriasis
Psoriatic nails

More images of nail psoriasis ...

What are the signs and symptoms?

The nail unit is made up of several parts; nail plate, nail bed, hyponychium, nail matrix, nail folds, cuticle, anchoring portion of the nail bed, and distal phalangeal bones. Signs of nail psoriasis vary according to the part of the nail affected and the nature of the deformity.

Sign/symptom Site Features
Oil drop or salmon patch Nail bed Translucent yellow-red discoloration in the nail bed, resembles drop of oil under nail plate
Pitting Proximal nail matrix Loss of parakeratotic cells from surface of nail plate
Beau's lines Proximal nail matrix Transverse lines in nails due to intermittent inflammation causing growth arrest lines
Leukonychia Midmatrix disease Areas of white nail plate due to foci of parakeratosis within the body of the nail plate
Subungual hyperkeratosis Hyponychium and nail bed Excessive proliferation of the nail bed and hyponychium. May lead to onycholysis.
Onycholysis Nail bed and hyponychium Nail plate separates from its underlying attachment to nail bed. Nail plate whitens and may detach. Secondary infection may occur.
Nail plate crumbling Nail bed or nail matrix Nail plate weakens due to disease of underlying structures
Acrodermatitis continua of Hallopeau Nail bed, nail matrix, tips of digits Nail plate destroyed by pustular eruption

A nail biopsy is occasionally needed to confirm the diagnosis of nail psoriasis as some other nail disorders may look similar.

What treatment is available?

There is no cure for nail psoriasis but it may improve by itself and may even return to a normal appearance. Although nail psoriasis is a benign condition, it can be uncomfortable and look unsightly causing significant dysfunction and psychological distress.

Several treatment options are available. Currently no one option has been identified as the best and all of them may prove disappointing. Treatment depends on the site and severity of the nail disease in individual patients.

Related information


  1. Ed Rook A, Wilkinson DS, Ebling FJB, Champion RH, Burton JL. Textbook of Dermatology. Fourth edition. Blackwell Scientific Publications.
  2. Cantoresi F, Caserini M, Bidoli A, Maggio F, Marino R, Carnevale C, Sorgi P, Palmieri R. randomized controlled trial of a water-soluble nail lacquer based on hydroxypropyl-chitosan (hPCh), in the management of nail psoriasis. Clinical, Cosmetic and Investigational Dermatology 2014:7;185-190

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Author: Vanessa Ngan, staff writer

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