Distinct phenotypes and prognosis between Jo-1 and non-Jo-1 subtypes in anti-synthetase syndrome: a retrospective...

Anti-synthetase syndrome (ASyS) is characterized by anti-aminoacyl-tRNA synthetase antibodies and heterogeneous multi-organ involvement. This study compared clinical phenotypes and outcomes between Jo-1-positive and non-Jo-1 ASyS patients in a Chinese cohort.

We retrospectively analyzed 184 ASyS patients treated between June 2017 and December 2020 at a tertiary academic center. Data included clinical records, laboratory results, CT imaging, and pulmonary function tests.

Among 184 patients, anti-aminoacyl-tRNA synthetase antibodies included Jo-1 (n = 76, 41.3%), EJ (n = 45, 24.5%), PL-7 (n = 35, 19.0%), PL-12 (n = 26, 14.1%), and OJ (n = 2, 1.1%). ILD prevalence was 94.0% (173/184), with 14 (7.6%) classified as RP-ILD. Malignancy was documented in 10 (5.4%) patients. Anti-Jo-1 patients showed significantly higher frequencies of myalgia (P < 0.001) and muscle weakness (P = 0.001), while non-Jo-1 patients exhibited more Gottron's sign (P = 0.005), malignancy (P = 0.039), RP-ILD (P = 0.034), and concurrent connective tissue diseases (P = 0.014). Laboratory analysis revealed higher CK, LDH, AST, ALT, and CD3 + CD8 + T-cell counts in Jo-1 patients (all P < 0.01), alongside lower complement C4 and ESR (P = 0.005 and P = 0.003). Survival analysis demonstrated a significantly better prognosis in Jo-1 patients (P = 0.002), with anti-PL-7 subgroup having the poorest outcome (P = 0.005). Multivariate logistic analysis identified RP-ILD and elevated serum ferritin as independent predictors of mortality.

Jo-1 and non-Jo-1 ASyS demonstrate distinct clinical phenotypes. Non-Jo-1 antibodies are associated with higher risks of RP-ILD and malignancy, indicating a more severe disease course and worse prognosis. Key Points • Anti-Jo-1 syndrome and non-Jo-1 anti-synthetase syndrome represent distinct clinical phenotypes with significant differences in organ involvement. • Non-Jo-1 antibody positivity is associated with a more severe disease profile, including higher risks of rapidly progressive interstitial lung disease and malignancy. • The anti-PL-7 subtype identifies a patient subgroup with the poorest long-term prognosis. • Rapidly progressive ILD and elevated serum ferritin are independent prognostic factors for mortality in anti-synthetase syndrome.