Scleroderma-like nailfold capillaroscopic abnormalities are associated with anti-U1-RNP antibodies and Raynaud's phenomenon in SLE patients.

This study aimed to evaluate the association between nailfold capillary abnormalities and the presence of Raynaud's phenomenon (RP), anti-U1-RNP, and anti-cardiolipin (aCL) antibodies in SLE patients. One-hundred SLE patients were studied. Widefield nailfold capillaroscopy was considered abnormal according to five criteria. Intercapillary distance, capillary width and capillary length were registered by videomorphometry in two fingers in 100 patients and in four fingers in 40 of these patients. Both the presence of alterated capillaroscopy and the presence of scleroderma-pattern (SD-pattern), characterized by the presence of avascular areas and enlarged or giant loops, were associated with the isolated presence of RP (P < 0.001) or anti-U1-RNP antibodies (P < 0.01), as well as with the simultaneous presence of RP and anti-U1RNP antibodies (P < 0.001). There was a negative association between the presence of aCL antibodies and SD-pattern (P < 0.05). Higher figures for the videomorphometric parameters capillary width, intercapillary distance and capillary length (measured on four fingers) were observed in patients with RP. Patients presenting both RP and anti-U1-RNP antibodies showed higher figures for intercapillary distance and capillary width. This study demonstrated significant association between nailfold capillaroscopic abnormalities and either RP or anti-U1-RNP antibodies in SLE patients. The association of RP, anti-U1-RNP antibodies, and 'scleroderma-like' findings on nailfold capillaroscopy (SD-pattern) in patients with SLE may suggest a new SLE subset with subclinical features of systemic sclerosis.