G-CAN endorsed labels and definitions of the disease elements of gout7
| Consensus label | Consensus definition | |
| Chemical elements | 1. MSU crystals | The pathogenic crystals in gout (chemical formula: C5H4N4NaO3) |
| 2. Urate | The circulating form of the final enzymatic product generated by xanthine oxidase in purine metabolism in humans (chemical formula: C5H3N4O3 –) | |
| 3. Hyperuricaemia* | Elevated blood urate concentration over the saturation threshold | |
| Clinical elements | 4. Gout flare | A clinically evident episode of acute inflammation induced by MSU crystals |
| 5. Intercritical gout | The asymptomatic period after or between gout flares, despite the persistence of MSU crystals | |
| 6. Chronic gouty arthritis | Persistent joint inflammation induced by MSU crystals | |
| 6a. G-CAN recommendation | The label ‘chronic gout’ should be avoided | |
| 7. Tophus | An ordered structure of MSU crystals and the associated host tissue response | |
| 8. Subcutaneous tophus | A tophus that is detectable by physical examination | |
| 9. Podagra | A gout flare at the first metatarsophalangeal joint | |
| Imaging elements | 10. Imaging evidence of MSU crystal deposition | Findings that are highly suggestive of MSU crystals on an imaging test |
| 11. Gouty bone erosion | Evidence of a cortical break in bone suggestive of gout (overhanging edge with sclerotic margin) |
*In British English, hyperuricaemia.
G-CAN, Gout, Hyperuricaemia and Crystal-Associated Disease Network; MSU, monosodium urate.