Contributions of dermoscopy in daily practice nailfold capillaroscopy

We read with great interest the article by Monfort et al.¹ demonstrating the value of nailfold dermoscopy to predict the absence of a scleroderma pattern on nailfold videocapillaroscopy (NVC) in the work-up for Raynaud's phenomenon (RP).

This study is valuable for the multidisciplinary microcirculatory community on different levels. Firstly, it suggests an easy-to-use screening tool for different specialists to exclude secondary RP, based on four ‘simple’ dermoscopy criteria. Dermoscopy has been shown in previous studies to be a suitable device for performing nailfold capillaroscopy. It has a reasonable cost and is easier to use than other devices such as a photomacrography system, stereomicroscope, digital USB microscope, ophthalmoscope or NVC. Secondly, commercially available image analysis software is currently limited to video capillaroscopes, allowing a standardized approach to analyse capillaroscopic characteristics and use in a research setting. This study emphasizes the advantages of dermoscopy and the difference we, as dermatologists accustomed to using and interpreting dermoscopy images, can make economically. These results underline the need for a more practical point of view in differentiating primary from secondary RP. The evolving landscape of artificial intelligence (AI) applications in dermatological diagnostics will certainly expand the future use of dermoscopy in the daily clinical work-up of RP.

Thirdly, this study also exposes several gaps in knowledge and controversies regarding the position of dermatoscopy in diagnosing connective tissue diseases. Because of its good validity and inter- and intra-observer reliability, it is suggested to be a useful tool for identifying capillary abnormalities suggestive of a scleroderma-spectrum disorder, comparable to NVC.² It is even proposed as part of the rheumatology fellow curriculum.³ Nevertheless, Monfort et al. clearly show in their study that dermoscopy has still poor specificity to detect capillary abnormalities.

In conclusion, this study shows that normal nailfold dermoscopy can predict normal NVC if four easy-to-observe criteria are absent, but also displays poor specificity for dermoscopy to detect capillary abnormalities, in contrast to previous literature. Differences in definitions between studies can explain different outcomes. AI could be a solution for a more accurate dermoscopy analysis in RP work-up in the future.

Yora Mostmans and Bertrand Richert declares no conflict of interest in relation to this work.