Matching between ctlinical examination and dermoscopy in patients with nail psoriasis: Should dermoscopy be used instead of clinical examination?

Background: Dermoscopy has emerged as a useful diagnostic tool to evaluate skin lesions, including psoriasis. We aimed to compare the clinical examination and digital dermoscopy findings of nail involvement in patients with psoriatic nails. Methods: This study included 60 patients with clinically diagnosed psoriasis. The nail findings and NAPSI were evaluated clinically and via dermoscopy, and then the severity of the disease was calculated using PASI criteria. Results: About 32 patients were males, with a median PASI score of 4.4, and pitting and subungual hyperkeratosis were the most common findings. The clinical and dermoscopic examination had a moderate diagnostic resemblance regarding onycholysis, subungual hyperkeratosis, and leukonychia. The resemblance between the two methods for the diagnosis of leukonychia in patients with a duration of disease <2 years (Kappa = 0.59) and 2-6 years was moderate (Kappa = 0.48), and for 6 years< was perfect (Kappa = 0.62). The resemblance for the diagnosis of subungual hyperkeratosis and onycholysis in subjects with a duration of disease <2 years was slight, and for 2-6 years and 6 years< were moderate. The resemblance between the NAPSI score by the two methods was also moderate (95%CI -0.89-0.81, Conclusion: Dermoscopy is an efficient, supportive, and non-invasive method providing a better diagnosis of nail psoriasis.