Major criteria | (1) Arthritis with 2 of 3 of the following findings |
| - Asymmetric |
| - Monoarthritis or oligoarthritis |
| - Lower limb involvement |
| (2) Preceding symptomatic infection with 1 or 2 of the following findings: |
| - Enteritis (defined as diarrhoea for at least 1 day, and 3 days to 6 weeks before the onset of arthritis) |
| - Urethritis (dysuria or discharge for at least 1 day, 3 days to 6 weeks before the onset of arthritis) |
Minor criteria | At least one of the following: |
| (1) Evidence of triggering infection: |
| - Positive urine ligase reaction or urethral/cervical swab for Chlamydia trachomatis
|
| - Positive stool culture for enteric pathogens associated with reactive arthritis |
| (2) Evidence of persistent synovial infection (positive immunohistology or PCR for Chlamydia) |