Joint and tendon subclinical involvement suggestive of gouty arthritis in asymptomatic hyperuricemia: an ultrasound controlled study

INTRODUCTION: In this study, we aimed to investigate ultrasonographic (US) changes suggestive of gouty arthritis in the hyaline cartilage, joints and tendons from asymptomatic individuals with hyperuricemia. METHODS: We conducted a cross-sectional, controlled study including US examinations of the knees and first metatarsal-phalangeal joints (first MTPJs), as well as of the tendons and enthesis of the lower limbs. Differences were estimated by χ(2 )or unpaired t-tests as appropriate. Associations were calculated using the Spearman's correlation coefficient rank test. RESULTS: Fifty asymptomatic individuals with hyperuricemia and 52 normouricemic subjects were included. Hyperechoic enhancement of the superficial margin of the hyaline cartilage (double contour sign) was found in 25% of the first MTPJs from hyperuricemic individuals, in contrast to none in the control group (P < 0.0001). Similar results were found on the femoral cartilage (17% versus 0; P < 0.0001). Patellar enthesopathy (12% versus 2.9%; P = 0.01) and tophi (6% versus 0; P = 0.01) as well as Achilles enthesopathy (15% versus 1.9%; P = 0.0007) were more frequent in hyperuricemic than in normouricemic individuals. Intra-articular tophi were found in eight hyperuricemic individuals but in none of the normouricemic subjects (P = 0.003). CONCLUSIONS: These data demonstrate that morphostructural changes suggestive of gouty arthritis induced by chronic hyperuricemia frequently occur in both intra- and extra-articular structures of clinically asymptomatic individuals.