[Nail-fold capillaroscopy in dermatology]

Nail-fold capillaroscopy is a non-invasive tool to study the microcirculation and is increasingly being used in dermatology, angiology and rheumatology. More recently, the use of video-capillaroscopy has allowed computer storage of capillaroscopic images (video-capillaroscopy), enabling evaluation of changes in capillaroscopic abnormalities during the follow-up of patients with systemic sclerosis or mixed connective tissue disease. Qualitative and quantitative assessment of the nail-fold dermal capillaries and of their organization can readily distinguish between a normal capillaroscopic pattern in primary Raynaud phenomenon and a specific sclerodermic pattern in secondary Raynaud phenomenon carrying a very high risk of systemic sclerosis. Apart from its important role as a diagnostic tool for distinguishing between primary and secondary Raynaud phenomenon, capillaroscopy is now used to predict the risk of development of digital ulcers and of future visceral complications in patients with systemic sclerosis. Moreover, nail-fold capillaroscopy is essential for differential diagnosis between connective tissue diseases, for the etiologic diagnosis of digital necrosis and diffuse interstitial lung disease, and in sclerodermiform syndromes.