Impact of double positive for anti-centromere and anti-SS-a/Ro antibodies on clinicopathological characteristics of primary Sjogren's syndrome: a retrospective cohort study

Objectives: The purpose of our study was to define the clinical characteristics of anti-centromere antibody and anti-SS-A/Ro antibody (ACA/SS-A) double positive Sjogren's syndrome (SS) and to clarify the clinical impact of these antibodies.Methods: We examined 108 patients (6 males, mean age 57.9 years) with SS who underwent labial salivary gland biopsy. The patients were divided into four groups by ACA and anti-SS-A/Ro antibody positivity. Symptoms, laboratory and pathological data, and scleroderma-related data were compared among the groups.Results: The cohort consisted of 16 ACA/SS-A double positive, 20 ACA single positive, 67 SS-A single positive, and 5 ACA/SS-A double negative SS. ACA/SS-A double positive SS were significantly older than SS-A single positive SS (mean age 71.1 vs. 53.1 years). They had higher EULAR Sjogren's syndrome disease activity index (ESSDAI) at diagnosis (mean 3.81 vs. 0.50) and higher serum IgG (mean 2009 vs. 1389mg/dL) than ACA single positive SS. No patients developed skin sclerosis during a mean follow-up period of 45.6 months (range: 1-178).Conclusion: These results demonstrate that ACA/SS-A double positive SS is distinct from ACA single positive and SSA single positive SS. The combination of ACA and anti-SS-A/Ro antibody in SS should deserve greater attention in clinical practice.