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

Abstract

IntroductionIn 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.MethodsWe 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 χ2 or unpaired t-tests as appropriate. Associations were calculated using the Spearman's correlation coefficient rank test.ResultsFifty 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).ConclusionsThese 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.

Clinical and Ultrasonic Characteristics of 100 New Crystal Proven Gouty Patients in a Rheumatology Clinic

“…The US findings of ISHE areas in the majority of patients confirm gout as a urate deposition disease, and the occurrence of ISHE areas was significantly correlated to disease duration and disease severity. The DC sign was significantly correlated to p-urate, which is in concordance with other studies describing DC in asymptomatic hyperuricaemic patients [16]. In a previous report DC sign was significantly correlated to s-urate but ISHE areas were not investigated [17].…”

Is the Double Contour Sign Specific for Gout? Or Only for Crystal Arthritis?

“…A false-negative DC sign may be due to poorly visualized joints with thin cartilage (tarsal joints) or damaged cartilage, as in osteoarthritis (OA). The DC sign has also been described in up to 29% of individuals with asymptomatic hyperuricemia 7,8 . It seems likely that this finding in asymptomatic hyperuricemia represents true subclinical MSU crystal deposition, because the DC sign was observed at much lower frequency in normouricemic controls (0-5%) in the same studies 7,8 .…”

“…The DC sign has also been described in up to 29% of individuals with asymptomatic hyperuricemia 7,8 . It seems likely that this finding in asymptomatic hyperuricemia represents true subclinical MSU crystal deposition, because the DC sign was observed at much lower frequency in normouricemic controls (0-5%) in the same studies 7,8 . Further, another study of 26 asymptomatic individuals with hyperuricemia, of whom 9 had urate crystals documented from joint fluid, DC, or hyperechoic cloudy area, had a positive predictive value of 82%, sensitivity of 100%, and specificity of 88% 9 .…”

Ultrasound as an Outcome Measure in Gout. A Validation Process by the OMERACT Ultrasound Working Group

“…In comparison to DECT, US appears to be more feasible because it is patient-friendly, safe and non-invasive, free of ionizing radiation, allows multiple target assessment in real time, and may aid the aspiration process for relevant material for microscopy 7 . Several published studies have highlighted the ability of US to detect crystal deposits and have addressed its possible role in very early diagnosis, based on their US findings indicative of gout in patients with asymptomatic hyperuricemia 7,8,9 .…”