Psoriasis – Nail Psoriasis
Nail changes are a very common finding in Psoriasis and I encounter Psoriatic nails often in both my The Woodlands dermatology and Conroe dermatology offices. Up to 50% of all patients with Psoriasis exhibit signs of Psoriatic nail involvement. Only 5% of patients with Psoriatic nails have no cutaneous signs of Psoriasis. There are many abnormal nail findings in Psoriatic nails and they depend on the exact location of the Psoriatic involvement in the nail. Plaques of Psoriasis can form on the nail matrix which disrupts the normal production of a healthy nail plate. Oil spots are the most diagnostic nail finding in Psoriasis in which red to yellow discoloration can be appreciated below the nail plate. Nail pitting is another very common finding which appears like small pin head size depressions in the nail plate due to loss of the parakeratotic scale in the nail plate. Horizontal indentations called Beau’s Lines can be seen in the nail plate due to temporary arrest of the nail plate growth. Leukonychia in which the entire nail plate is white due to foci of parakeratotic scale in the nail plate can occur. Onycholysis can occur which is the nail plate splitting off of the nail bed. To confirm that a patient has nail Psoriasis, a biopsy in the nail matrix or nail bed can be performed. Treatment of nail Psoriasis is difficult but topical steroids are used on the nail fold as well as intralesional kenalog injections. PUVA light therapy has also had some success. Many patients treated with systemic agents for Psoriasis also note improvement in their nail Psoriasis.