Nailfold capillaroscopy in rheumatic connective tissue diseases.

Capillaroscopy is a non-invasive examination used for imaging of capillary vessels of the papillary layer of the finger nailfold. It allows the detection of microcirculation disorders in systemic connective tissue diseases. According to the "Fast Track" algorithm recommended by the European Alliance of Associations for Rheumatology, capillaroscopic findings should be categorized as a scleroderma or non-scleroderma pattern. Scleroderma microangiopathy may also occur in polymyositis and "scleroderma spectrum" diseases such as dermatomyositis, mixed connective tissue disease, or undifferentiated connective tissue disease. These capillaroscopic features are called scleroderma-like microangiopathy. Numerous studies have shown a correlation between capillaroscopic patterns and the severity of organ involvement. Available data indicate the occurrence of capillaroscopic changes in patients with other systemic connective tissue diseases, such as systemic lupus erythematosus, Sjögren's disease, rheumatoid arthritis, and antiphospholipid syndrome. The importance of capillaroscopy in diseases beyond the scleroderma spectrum requires further investigation.