Scleroderma-specific autoantibodies: Should they be included in the diagnostic work-up for Sjögren's syndrome?

• Published in: Seminars in arthritis and rheumatism 2022-08, Vol.55, p.152026-152026, Article 152026
• Main Authors: Marketos, Nikolaos, Koulouri, Vasiliki, Piperi, Evangelia P., Georgaki, Maria E., Nikitakis, Nikolaos G., Mavragani, Clio P.
• Format: Article
• Language: English
• Subjects: anti-La/SSB; anti-Ro/SSA; Antibodies, Antinuclear; Autoantibodies; Humans; Scleroderma, Localized; Scleroderma, Systemic - complications; Scleroderma, Systemic - diagnosis; Scleroderma-specific autoantibodies; Sicca; Sjogren's Syndrome - complications; Sjögren's syndrome
• ISSN: 0049-0172; 1532-866X
• DOI: 10.1016/j.semarthrit.2022.152026

•Systemic sclerosis (SSc) specific autoantibodies are frequently detected in unselected patients with sicca complaints evaluated for Sjögren's syndrome.•At strong titers, they are associated with histopathological features compatible with Sjögren's syndrome (SS), independently of anti-Ro/SSA and La/SSB status.•These data possibly imply SSc antibodies as an additional tool in the diagnosis and classification of Sjögren's syndrome. Sicca complaints are a frequent reason for rheumatologic consultation. Testing for specific antibodies against Ro/SSA and La/SSB antigens and minor salivary gland (MSG) biopsy are among the main tools implemented in the diagnostic work-up. Anticentromere antibodies and sicca manifestations are frequently detected in Sjögren's syndrome (SS) and systemic sclerosis (SSc), respectively. Herein, we aimed to determine the frequency and clinical associations of a wide spectrum of scleroderma (SSc)-specific autoantibodies in consecutive patients referred for evaluation of possible SS. Demographic, clinico-pathological, and laboratory data were recorded in 216 consecutive patients with sicca complaints. All study participants were tested for SSc-specific autoantibodies (against CENP, PM/Scl, Scl-70, Ku, NOR90, RP11, RP155, fibrillarin, PDGFR, and Th/To) using a commercially available immunoblot kit. According to band intensity, the identified autoantibodies were further classified in those with strong and medium titers. SSc-specific autoantibodies were detected in 41.7% (90/216) patients evaluated (19% at strong, 22.7% at medium titers) without significant differences between anti-Ro/SSA positive and negative groups. At strong titers was significantly higher in patients with MSG biopsies fulfilling SS histopathological criteria (30% vs 12.5%, p = 0.009). This association remained significant after adjustment for antibodies against Ro/SSA and La/SSB autoantigens [OR 95% (CI): 4.1 (1.5–10.6)]. SSc-specific autoantibodies are frequently detected among patients presenting with sicca complaints and at strong but not medium titers are independently associated with MSG biopsy positivity. Taken together, these data imply a useful role of SSc antibody testing in the diagnostic work-up and possibly in the classification criteria for SS.