Further exploratory analyses demonstrated that self-reported chlamydial infection was significantly associated with ACPA positivity (aOR = 2.66; 95% CI: 1.24, 5.36), RF positivity (aOR = 1.83; 95% CI: 1.1, 2.93) and double positivity (aOR = 4.97; 95% CI: 1.43, 16.05) (Table 2). Here, PRTN3 is linked to chlamydia trachomatis infectious disease.