Psoriasis is an inflammatory chronic recurrent skin disease affecting 1-3% of population 1. Psoriatic lesions characterized by erythematous-squamous skin plaques due to the presence of epidermal hyper-proliferation 2. Psoriasis either present alone or in combination may involve skin, joints, and nails 3. Nail psoriasis represents 50% of psoriatic patients. It may affect some or all nails and may cause mild cosmetic changes or extend to severe pain and disability. 4. Isolated nail psoriasis is seen in 5-10% of patients 5. Nail involvement is a relevant manifestation of psoriasis may be associated with life impairment. Accordingly, management of psoriasis should include a special focus on nail involvement 6. Pitting, onycholysis with erythematous bordersand salmon colored patches on the nail bed, are the main signs for nail psoriasis. Other signs are also seen like Splinter hemorrhages, nail-bed hyperkeratosis, nail thickening, crumbling, paronychia, leukonychia, trachyonychia and erythema of the lunula 7.
The severity of nail psoriasis is assisted by the nail psoriasis Severity Index (NAPSI) which designed to grade disease 8. The NAPSI score and a modified version of this severity index score have been used to monitor the response to nail psoriasis therapy 9. Dermoscopy is a highly practical diagnostic technique that allows for an in vivo evaluation of the morphological features of pigmented and non-pigmented skin lesions 10. In the last few years, dermoscopy has been widely used as an effective tool in the diagnosis of nail diseases 11. Dermoscop was used as a good a tool to detect signs of psoriasis in the nails and to find if any signs can help in early detection of nail affection 12.
Sever nail psoriasis can lead to functional or emotional impairment, so, every patient should be treated even those with sole nail change. Topical or laser treatments may be suitable for limited disease or may take part in combination therapies for more severe disease, while classical systemic agents or biologic treatments are preserved for severe cases with extensive cutaneous disease or psoriatic arthritis 13. Topical therapy is limited by difficulty in achieving adequate antipsoriatic concentrations at the the inflammatory sites 14. Nail psoriasis therapy with biologics showed faster, better, and more sustained response 15. Infliximab taken systemically was found to be effective therapy for nail psoriasis 16. Intralesional corticosteroids injections are considered to be a standard treatment for nail psoriasis 17. Triamcinolone acetonide used in doses of 2.5–10 mg/mL at four injection sites (two into the proximal nail fold and two in the lateral nail fold), twice monthly for 5-6 months. Injections to the proximal nail fold are very effective in treating nail matrix disease such as pitting or ridging. 18. Nail Psoriasis Severity Index (NAPSI) score was reduced with improvement in both nail bed and nail matrix lesions was seen after three treatment sessions using 595 nm PDL monthly 19.