Consensus-based evaluation of dermatoscopy versus nailfold videocapillaroscopy in Raynaud's phenomenon linking USA and Europe: a European League against Rheumatism study group on microcirculation in rheumatic diseases project.

Nailfold videocapillaroscopy (NVC) is the current gold standard for detection and quantification of capillary abnormalities in Raynaud's phenomenon (RP). The objective of this study is to evaluate the role of dermatoscopy as a further screening tool in RP. Nailfold capillaries of RP patients were examined by a hand-held non-contact polarised dermatoscope connected to the digital camera (D1) and connected to an iPad (D2). Both dermatoscopic images were marked with an arrowhead. NVC examination was evaluated at the arrowhead. Single blinded reader performed all examinations. NVC was graded as per standard of European League against Rheumatism (EULAR) study group on microcirculation in rheumatic diseases. Consensus evaluation of dermatoscopy characteristics/grade was determined and each dermatoscopic image was given a final impression of 'normal', 'non-specific' or 'scleroderma' pattern. The final interpretation by both techniques was compared after completion of the blinded reading. Classification of 100 consecutive dermatoscopic images resulted in 37 (wide view) 'non-interpretable', 2 'normal', 48 'non-specific' and 13 'scleroderma' pattern with D1; 23 'non-interpretable', 4 'normal', 52 'non-specific' and 21 'scleroderma' pattern by the experts with D2; 0 non-interpretable, 4 normal, 13 non-specific and 83 'scleroderma' pattern with NVC. Overall, 50% of dermatoscopic images were classified as non-specific and 30% were classified as non-interpretable in RP patients. However, all images classified by dermatoscopy as "normal" or as overt "scleroderma" pattern were confirmed by concomitant NVC analysis. These findings demonstrate tenuous promise for dermatoscopy as a tool for the initial screening of nailfold capillaries in RP. Further regular work up with NVC is needed to further clarify non-interpretable and non-specific findings possibly related to non-scleroderma patterns.