The "snowstorm" sign refers to the ultrasound appearance of motile hyperechoic specks within synovial fluid and has been reported to have a high specificity for gout. We describe three additional etiologies commonly encountered in the rheumatology clinic that can produce a snowstorm: calcium pyrophosphate deposition disease, fibrin collections/rice bodies, and gas bubbles in viscous synovial fluid.
Keywords: Calcium pyrophosphate; gout; rice body; snowstorm.
Copyright: © 2020 Journal of Medical Ultrasound.