Applying ultrasound in the diagnosis of gout
Gout is an inflammatory disorder characterized by hyperuricemia and the deposition of monosodium urate crystals, resulting in episodic gout flares, gouty arthropathy, and tophi formation.
Accurate diagnosis is critical for appropriate treatment of gout, but the differential diagnosis between gout and other causes of arthritis can be challenging.
The gold standard for the diagnosis of gout is the microscopic analysis of synovial fluid aspirate, which reveals negatively birefringent needle-shaped monosodium urate crystals in polarized light microscopy.
However, joint aspiration can be technically challenging in patients with small amounts of joint fluid, and identification via joint aspiration is not always possible. In addition, synovial fluid aspiration may not reveal uric acid crystals in up to 25% of patients with gout.
Ultrasound (US) may come to replace conventional invasive examinations in clinical practice.
A recent meta-analysis demonstrates that US offers good diagnostic accuracy. It helps in establishing the diagnosis of gout and can assist in differentiating gout from other arthritic diseases.
Therefore, US may prove to be an important diagnostic modality in the noninvasive assessment of gout.
> From: Lee et al., Semin Arthritis Rheum 47 (2018) 703-709. All rights reserved to Elsevier Inc. Click here for the online summary.