Background the nail unit is a shared topic of interest both for dermatologist and rheumatologist . It is easy to study using imaging techniques such as ultrasonography. The nail was considered one of the possible target of assessment for the disease, especially when ultrasonography is performed. Ultrasound imaging of nails is a quite new technique, available since high frequencies probes were introduced in musculoskeletal examination and nail was considered one of the possible target for assessing the disease and defining its prognosis [2,3].
Objectives to evaluate the presence of the nail involvement and subclinical alterations using ultrasonography in psoriasis and psoriatic arthritis.
Methods the study sample included 82 patients affected by psoriasis and/or psoriatic arthritis and 50 healthy controls (HC). The patients were consecutively enrolled during their routine visit in the outpatient clinic and they performed clinical and ultrasonographic evaluation of the nail. Activity indexes (DAPSA, PASI, NAPSI) and other clinimetric parameters were considered.
Results multivariate analysis of variance (mANOVA) was performed between groups and the nail plate and nail bed thickness, PASI, NAPSI, age and BMI were considered (table 1). Post hoc analysis underlined the differences between groups, in particular between healthy and affected. The lesions for nail plate and nail bed in the PASI score were analyzed using Pearson's chi square test and, secondary, odd ratios for significant results were calculated. Nail plate thickness and nail bed thickness were correlated with PASI, NAPSI, BMI and DAPSA. ROC curves were calculated obtaining also quantitative cut offs for nail plate and nail bed thickness in the affected vs healthy ones.
Conclusions the application of ultrasonography is of potential advantages supported by the data of this study and strengthens the information available in literature, also adding quantitative parameters for the ultrasonography of the nail.
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Raposo I, Torres T. Nail psoriasis as a predictor of the development of psoriatic arthritis. Actas Dermo-Sifiliográficas Engl Ed 2015;106:452–7. doi: 10.1016/j.adengl.2015.02.001.
Gutierrez M, Filippucci E, De Angelis R, et al. A sonographic spectrum of psoriatic arthritis: “the five targets.” Clin Rheumatol 2010;29:133–42. doi: 10.1007/s10067-009-1292-y.
Disclosure of Interest None declared