The presence of 4 or more of 8 clinical findings—multiple attacks of acute arthritis, rapid pain and swelling, monarthritis or oligoarthritis or both, podagra, erythema, tophi, unilateral attacks, and hyperuricemia—is highly suggestive of a diagnosis of gout when monosodium urate (MSU) crystals in synovial fluid or tophi cannot be demonstrated. This chronic gout diagnosis proposal is based on clinical data from the American College of Rheumatology's (ACR) proposed classification criteria and European League Against Rheumatism (EULAR) evidence-based recommendations for diagnosis of gout.
Peláez-Ballestas and colleagues examined data from 549 patients to determine which criteria from the ACR and the EULAR are fulfilled by patients identified by their physicians as having gout. They also analyzed samples for MSU crystals in 15% of the patients.
Most patients with acute gout had hyperuricemia, rapid onset of pain/swelling, and podagra—criteria shared by the ACR and the EULAR systems. Most patients had a history of multiple attacks of acute arthritis affecting at least 1 joint. About half had asymmetrical joint swelling and subcortical cysts without erosions; a few more than half had erythema and swelling.
The authors noted that documenting the presence of MSU crystals increases the diagnostic accuracy of these findings.