Gout Diagnosis Calculator

A total score of ≥ 8 out of a maximum of 23 points classifies a subject as having gout according to the 2015 ACR-EULAR criteria. These criteria were designed for research classification purposes and should not replace clinical diagnosis. Scores below 8 make a gout classification less likely, while very low scores (especially with negative synovial fluid analysis) suggest an alternative diagnosis.

Allopurinol lowers serum urate levels, which can mobilise urate crystals already deposited in joints, triggering a new inflammatory flare. This is why urate-lowering therapy like allopurinol should not be started during an acute attack. When it is initiated, it should be accompanied by prophylactic colchicine or an NSAID for several months to prevent flares during the transition period.

Yes. During an acute gout flare, serum uric acid can be falsely low because the acute inflammatory state drives urate into tissues. This is why the ACR-EULAR criteria recommend measuring serum urate during the intercritical period (between attacks) for the most accurate result. A score of −4 is actually assigned when urate is below 4 mg/dL, reflecting its negative predictive value.

First-line treatment for an acute gout attack includes colchicine (1 mg followed by 0.5 mg one hour later), NSAIDs (e.g. naproxen or indomethacin at full doses), or corticosteroids if the former are contraindicated. Ice application and joint rest also provide symptomatic relief. Urate-lowering therapy should not be started or stopped during an acute flare.

High serum uric acid (hyperuricaemia) can result from reduced renal excretion (most common, ~90% of cases) or overproduction of urate. Risk factors include a purine-rich diet (red meat, shellfish, alcohol — especially beer), obesity, metabolic syndrome, chronic kidney disease, diuretic use, and certain genetic conditions like Lesch-Nyhan syndrome.

No. The ACR-EULAR Gout Classification Criteria were developed for research purposes — specifically to identify patients eligible for clinical studies — not for individual clinical diagnosis. A rheumatologist or physician should evaluate the full clinical picture, including medical history, physical examination, and laboratory tests, before confirming a diagnosis of gout.

If monosodium urate (MSU) crystals are identified by polarised light microscopy in a symptomatic joint, bursa, or tophus, the patient is automatically classified as having gout without needing to complete the full scoring system. This is the gold standard for gout diagnosis and overrides the point-based scoring entirely.

The ACR-EULAR criteria recognise two imaging modalities: ultrasound showing a double contour sign (hyperechoic band over cartilage surface) or dual-energy CT (DECT) demonstrating urate deposition, both scoring +4 points. Plain X-ray showing at least one gout-related erosion (cortical breakthrough with sclerotic margin) also scores +4 points in the imaging damage domain.