Nailfold capillaroscopy in systemic diseases: short overview for internal medicine

Nailfold capillaroscopy (NFC) is now one of the main imaging tools in systemic sclerosis and imposed over time as an easy, non-invasive method for the nailfold microvascular bed assessment. In qualitative NFC normal pattern is characterized by homogeneous, parallel fashion arrangement of the last capillaries row as well as by capillaries with hairpin or non-specific variations like tortuous and/ or crossing shape. Nailfold capillaroscopy is strongly recommended for evaluation of all patients with Raynaud phenomenon. Appearance of giant capillaries is chronologically the first relevant finding for scleroderma spectrum disorders development (systemic sclerosis, dermatomyositis, undifferentiated and mixed connective tissue disease). Collapses of the giant loops generate microhemorrhages and further capillary loss with subsequent hypoxia, and neoangiogenesis seen as ramified/ bushy capillaries. Nailfold capillaroscopy is indicated especially in systemic sclerosis, being also included in the classification criteria. Based on these major NFC pathologic findings (giant capillaries, microhemorrhages, avascularity and neoangiogenesis), three evolutive stages were described in systemic sclerosis, namely the early, active, and late scleroderma pattern. In other connective tissue diseases than those scleroderma-related, like systemic lupus erythematosus, psoriatic arthritis, or antiphospholipid syndrome, the interest for capillaroscopy is growing, but the attempts of defining specific characteristics failed until now. Besides qualitative NFC, semiquantitative and quantitative capillaroscopic assessments were proposed for more accurate evaluation. Lately, automated systems are under development. There is still need of more studies to sustain the nailfold capillaroscopy validity as diagnostic and prognostic test.