Table 1.

Diagnostic criteria for reactive arthritis

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

A “definite” diagnosis of ReA is based on the completion of both major criteria and a relevant minor criterion, while both major criteria characterize a “probable” diagnosis but no relevant minor criterion or one major criterion and one or more of the minor criteria