In this radiology lecture, we review the ultrasound appearance of gout!

Key teaching points include:

Gout is a crystal arthropathy due to monosodium urate crystal deposition in and around joints
Most common in males over age 40
Risk factors: Metabolic (hyperuricemia, obesity, diabetes, hypertension), renal (chronic kidney disease), dietary (high purine foods, sugary drinks, alcohol), and genetic (family history)
Typically presents as acute monoarthritis with a red, inflamed, swollen joint. First metatarsophalangeal joint most common site of involvement (podagra)
Can progress to asymmetric polyarticular disease and chronic tophaceous gout
Ultrasound findings include: Joint effusion +/- hyperechoic foci (crystals/microtophi), synovial hypertrophy, and erosions typically at medial aspect of distal first metatarsal
Erosions are juxtaarticular in distribution with overhanging edges yielding a “punched-out” appearance
Gouty tophus: Amorphous, echogenic area containing internal hyperechoic foci surrounded by an anechoic inflammatory halo. May have associated cortical erosions
Tophi may involve tendons, tendon sheaths, and bursae. Other common sites include olecranon region (elbow), patellar and popliteal tendons (knee)
Double contour sign, AKA urate icing: Hyperechoic monosodium urate crystals coating hyaline cartilage surface. Disappears when serum urate levels drop below 6 mg/dL*
Distinct from chondrocalcinosis seen in calcium pyrophosphate deposition disease which will have echogenic crystals within cartilage as opposed to on surface

References:

*Thiele RG, Schlesinger N. Ultrasonography shows disappearance of monosodium urate crystal deposition on hyaline cartilage after sustained normouricemia is achieved. Rheumatol Int. 2010;30(4):495–503
Jacobson JA. Fundamentals of Musculoskeletal Ultrasound. 3rd ed. Elsevier; 2018

To learn more about the Samsung RS85 Prestige ultrasound system, please visit: https://www.bostonimaging.com/rs85-prestige-ultrasound-system-4

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This video is for informational purposes only. It does not replace the advice or counsel of a doctor or health care professional.

Ultrasound of Gout