Title : Clinical, immunological, and cytokine profiles of primary Sjögren’s syndrome in a Western Algerian population
Abstract:
Background: Primary Sjögren’s syndrome (pSS) is a complex systemic autoimmune disease characterized by significant clinical and biological heterogeneity, driven by intricate genetic and immunological factors. Data regarding North African pSS cohorts remain scarce. This study aims to investigate the clinical, immunological, and genetic characteristics of pSS patients from Western Algeria and explore their correlations with disease expression.
Patients and Methods: A descriptive and analytical case-control study was conducted on a well-characterized cohort of pSS patients from Western Algeria diagnosed according to international criteria. Comprehensive clinical evaluations assessed glandular (ocular/oral dryness, parotidomegaly) and extra-glandular manifestations (articular, muscular, pulmonary, renal, and neurological involvements). The immunological profile included antinuclear antibodies (ANA), anti-Ro/SSA, anti-La/SSB, rheumatoid factor (RF), serum gamma-globulin levels, complement fractions, and serum interferon-gamma (IFN-$\gamma$) concentrations quantified by ELISA. HLA-DR and HLA-DQ class II polymorphisms were also evaluated.
Results: The cohort exhibited a mean age at diagnosis of 50.52 $\pm$ 12.41 years with a pronounced female predominance (sex-ratio F/H of 12:1; 90.24% females). Glandular involvement was universal (100%), predominated by ocular (87.2%) and oral (88.5%) dryness. Extra-glandular manifestations were observed in the majority of patients, with articular involvement being the most frequent (77.9%), followed by muscular (45.5%) and vascular/neurological manifestations. Immunologically, anti-SSA/Ro antibodies were detected in 67% of patients and showed a significant positive correlation with hypergammaglobulinemia ($p = 0.011$). Serum IFN-$\gamma$ was positive in 53.12% of cases and demonstrated a highly significant association with earlier disease onset and elevated titers of anti-SSA/Ro and anti-SSB/La autoantibodies ($p < 0.001$). Genetic screening revealed characteristic distributions of HLA-DRB1 and HLA-DQB1 alleles within this population, mirroring broader Mediterranean and Caucasian trends while highlighting regional specificities.
Conclusion: This study provides a comprehensive overview of pSS in Western Algeria, emphasizing the critical role of Th1-associated cytokines like IFN-γ and autoantibody profiles in disease
severity and early onset. These findings contribute to a deeper understanding of pSS immunopathology across diverse ethnic backgrounds and underscore the need for integrated immunogenetic surveillance in autoimmune disorders.
