The aim of this study is to compare the efficacy of excimer laser in combination with intralesional MTX injection to intralesional MTX injection alone in treating nail psoriasis

Psoriasis is a chronic inflammatory disease affecting the skin, nails, and joints. Approximately 61% of psoriatic patients have nail involvement. This percentage can increase up to 90% in patients with psoriatic arthritis. Clinically, nail disease has many presentations depending on the location of the inflammatory process in either the matrix, the nail bed, or the periungual tissue, which results in distinct injury patterns.

Nail psoriasis can lead to impairment in the quality of life and work function due to pain, discomfort, and poor esthetic aspect. Treating nail involvement is important in improving the health outcomes and quality of life among patients with psoriasis. Nail psoriasis is a clinical diagnosis generally made in the context of existing psoriatic skin lesions. The nail psoriasis severity index (NAPSI) has recently been reported as a possible reproducible, objective, and simple tool for clinical assessment of psoriatic nail disease.

Treatment of nail psoriasis is challenging because of the anatomical properties of the nail unit that act as a barrier to active drug delivery and the naturally slow growth rate of the nail plate, which often delays noticeable clinical responses by months. Treatment options available for nail psoriasis include topical therapy, intralesional injections, and systemic and biologic agents. Poor penetration of topical therapy into the nail and surrounding tissue, adverse effects and monitoring of systemic therapies, and patient adherence to therapy make the treatment of nail psoriasis a challenge.

Few publications have been recently concerned intralesional injection of methotrexate in nail psoriasis. This therapy was documented for the first time in 2011. Intramatricial injection of methotrexate is an interesting intralesional therapy as it provides a higher concentration of the drug at the site of action, while avoiding the complications seen with triamcinolone acetonide (injection site atrophy, disappearance of the phalanx under injection, or tendon rupture) The use of excimer laser for the treatment of psoriasis was first documented in 1997. The excimer laser induces T-cell apoptosis characterized by breaks in DNA strands as well as expression of mitochondrial proteins associated with cell death.

Inclusion Criteria:

• patients with bilateral fingernail psoriasis will be recruited. The diagnosis will be based upon the clinical characteristics of nail psoriasis.
• Patients will be included after they have stopped any systemic therapy for at least 8 weeks.

Exclusion Criteria:

• Pregnant or lactating woman
• Patients with history of photosensitivity or keloid formation.