Immunological profile in primary Sjögren syndrome: Clinical significance, prognosis and long-term evolution to other auto-immune disease

Objective To study evolution of pSS immunological profile, impact on pSS activity and the long-term evolution of patients with atypical auto-antibodies in a bicentric cohort of patients with pSS (n = 445, mean age 53.6 ± 14 years, mean follow-up 76.1 ± 51 months). Results 212 patients were SSA positive and 131 were both SSA and SSB positive. During follow-up, SSA antibodies disappear in 8 patients; 2 of them exhibit new systemic complications of pSS. 68 patients had cryoglobulinemia. 52 patients had other anti-nuclear antibodies (ANA) specificities: anti-RNP (n = 12), anti-centromere (n = 14), anti-DNA native (n = 19), anti-Scl70 (n = 3), anti-JO1 (n = 3), anti-Sm (n = 3) and anti-histone (n = 1). Fourteen patients developed ANA-associated auto-immune disease during the follow-up: 5 polymyositis (mean apparition delay 78 months), 6 systemic lupus erythematosus (mean occurrence delay 77 months) and 2 systemic sclerosis (mean occurrence delay 133 ± 64 months). Among these 14 patients, only three presented atypical-ANA at pSS diagnosis. Cryoglobulinemia and anti-SSA and SSB antibodies at diagnosis were associated with new systemic involvements. In conclusion Cryoglobulinemia and SSA/SSB positivity are associated with systemic activity after diagnosis in pSS. Although atypical ANA are found in 12% of the cases, long-term evolution to ANA associated auto-immune diseases concerned patients with active immunological profile and extra-glandular manifestations.