The increase in serum urate concentrations (hyperuricaemia, ≥7.0 mg/dL) creates crystals, which promote inflammation and joint lesions. Ultrasonography can reveal these urate deposits. The presence of crystals suggests that a patient with hyperuricaemia is actually experiencing asymptomatic gout, and that a patient with gout without subcutaneous tophi could experience tophaceous gout. The information offered by ultrasound (double contour sign and hyperechoic concretions mimicking clouds) enables a more specific classification of hyperuricaemia and gout. Additionally, this information can lead to relevant changes in terms of the diagnosis and therapeutic approach for patients with hyperuricaemia and gout.
- Double contour sign