Microscopic Nail Clipping Findings in Patients With Psoriasis

Abstract

Nail clippings from patients with psoriasis present abnormally thickened subungual region with prominent hypercorneocytosis, serous lakes, bacteria, neutrophils, and blood collections. If fungi are present, usually there are spores. Clinically, normal-looking nails in patients with psoriasis can present microscopic abnormalities.

Clinical features and nail clippings in 52 children with psoriasis

“…Concerning nail plate thickness, our findings were similar to those that Werner and colleagues described . In adults with onychodystrophy, they observed that median thickness of the nail plate was 0.4 mm (range 0.26‐0.85 mm) and that median subungual region thickness was 0.15 mm (range 0‐0.7 mm).…”

“…Neutrophils were found in 12% of patients with visible onychodystrophy, versus 2% of those with normal appearance ( P = .07). Serous lakes were present in 46% of the dystrophic nails and in 33% of the clinically healthy nails ( P = .21) . In our pediatric population, neutrophils were found in 6 samples (7.6%) and serous lakes in 15 (19%).…”

“…Several layers of parakeratosis, serous lakes, and neutrophils were the main findings in psoriatic dystrophic nails. The authors also found microscopic alterations in normal‐looking nails …”

“…The procedure is quick and usually painless and can be repeated as many times as needed . It improves diagnosis of onychomycosis and can complement diagnosis of skin diseases with nail involvement, such as psoriasis . Machler and colleagues first used this method in adults with psoriasis in 1998.…”

“…They described only the presence of parakeratosis and neutrophils in few cases of nail dystrophy caused by psoriasis . Werner and colleagues, in a study of 96 adult patients with psoriasis, compared microscopic features of visually dystrophic nails and apparently normal ones using nail clipping . Several layers of parakeratosis, serous lakes, and neutrophils were the main findings in psoriatic dystrophic nails.…”