Capillaroscopy: a useful tool in the early diagnosis of connective tissue disease and non-scleroderma spectrum disorders.

Background: Detection of early capillaroscopic alterations in the preclinical phase may prove useful in patients with non-scleroderma connective tissue disease (CTD). We aimed to verify whether certain capillaroscopic alterations, alone or in combination, might be predictive of CTD.

Methods: We retrospectively collected data on patients with Raynaud's phenomenon who underwent capillaroscopy conducted by highly expert examiners with a degree in vascular medicine at our institutions. Included subjects were divided in two groups: those developing rheumatic disease during follow-up, and those without subsequent diagnosis of CTD. Notably, we excluded subjects who presented with an evident scleroderma pattern or rheumatic disease during their initial examination.

Results: We included a total of 76 patients, 60 of whom developed CTD during follow-up, which spanned in this group 23±7 months, and 16 who did not develop CTD during follow-up, which spanned 23±9 months. The following features were significantly associated with Raynaud's phenomenon: 1) angiotectonic disorder (P<0.001); 2) nonhomogeneous loop morphology (P<0.001); 3) avascular areas (P<0.001); 4) pseudo-avascular areas (P<0.001), and, albeit to a lesser degree; and 5) ectasias (P<0.050). Notably, the initial capillaroscopic pattern did not undergo any changes in subsequent tests.

Conclusions: Although certain pathological characteristics of the capillaroscopic pattern are non-specific and not diagnostic if considered individually, they can be significantly suggestive for latent CTD when found in combination. At the very least, they warrant an in-depth diagnostic analysis and a lengthy follow-up.