Introduction: Anti-centromere antibody (ACA)-positive Sjögren's syndrome (SS) is considered a subtype of SS. ACA-positive SS patients display several features, such as Raynaud's phenomenon, sclerodactyly, and extraglandular dysfunction. However, information on the features of ACA-positive SS is insufficient and the clinical significance of ACA in SS has not been fully established. The aim of this study was to clarify the features of ACA-positive SS.
Methods: All patients with primary SS who visited our hospital were enrolled. Clinical information and immunological tests were collected and statistically analyzed.
Results: A total of 585 patients were classified as having primary SS. They were divided into four groups by serum ACA and anti-SS-A antibody status as follows: 22 had ACA only (ACA alone), 464 had anti-SS-A antibodies only (SS-A alone), 26 had both ACA and anti-SS-A antibodies (double-positive), and 73 had neither ACA nor anti-SS-A antibodies (seronegative). The proportion of patients with dryness did not differ between the four groups. The proportion of patients with Raynaud's phenomenon or sclerodactyly was higher in the ACA alone and double-positive groups. The proportion of patients with increased serum IgG or IgA was 0 and 5% in the ACA alone group, 61 and 20% in the SS-A alone group, 52 and 28% in the double-positive group, and 20 and 4% in the seronegative group (p < 0.01 and p < 0.01), respectively. The proportion of patients with leukocytopenia was significantly lower in the SS-A-negative group than in the other groups.
Conclusions: Our study identified characteristics of ACA-positive SS patients that differ from those of anti-SS-A antibody-positive SS patients.
Keywords: Anti-SS-A antibody; Anti-centromere antibody; Sjögren’s syndrome.