To describe the capillaroscopic abnormalities observed in patients with primary Sjögren's Syndrome (pSS), associating them with clinical and serologic features, and comparing these findings to those observed in normal controls.
Sixty-one consecutive patients with pSS were studied by clinical evaluation, serology, and nailfold capillary microscopy (NCM). Twenty-one normal controls were also examined. Capillaroscopic findings were recorded in a standardized way by a blinded observer Capillary loss on NCM was evaluated using a deletion score.
NCM was normal in 59.0% of pSS patients; 29.5% had non-specific abnormalities, and 11.5% presented a SD-like pattern. Patients presented a higher deletion score than controls (p < 0.001). Other capillaroscopic parameters (number of dilated, bizarre, and meandering capillaries; capillary hemorrhages; venous plexus visibility) did not differ significantly between patients and controls. Among patients, the deletion score was higher in those with systemic manifestations (p = 0.022) and Raynaud's phenomenon (p = 0.050). No association between the presence of antinuclear antibodies, rheumatoid factor, anti-SSA/Ro and anti-SSB/La with qualitative or quantitative NCM findings was found. Among the 7 patients with SD-like pattern on NCM, 6 had Raynaud's phenomenon, but only 2 presented autoantibodies related to systemic sclerosis (1 with anticentromere and 1 with low titer antitopoisomerase I). None of these patients met the ACR criteria for SSc.
SD-like pattern on NCM is observed in a small but significant proportion of pSS patients. The association of systemic involvement with a higher deletion score may be related to the hypothesis that these manifestations represent clinical expressions of systemic vasculitis.