Levels of Cytokines and MicroRNAs in Individuals With Asymptomatic Hyperuricemia and Ultrasonographic Findings of Gout: A Bench-to-Bedside Approach.

OBJECTIVE: To assess potential associations among serum cytokines and microRNA (miR) levels with ultrasound (US) findings suggestive of urate deposits in chronic asymptomatic hyperuricemia and gout. METHODS: All participants underwent musculoskeletal US and measurements of serum interleukin-1ß (IL-1ß), IL-2, IL-4, IL-5, IL-6, IL-8, IL-10, IL-12, IL-13, interferon-γ, tumor necrosis factor, monocyte chemoattractant protein 1, and epithelial neutrophil-activating peptide 78, as well as miR-146a, miR-155, and miR-223 levels. RESULTS: Thirty individuals with asymptomatic hyperuricemia, 31 normouricemic controls, and 30 patients with gout were included. The frequency of synovitis and double contour sign using US was similar between asymptomatic hyperuricemia (67% and 27%, respectively) and patients with gout (77% and 27%, respectively), and each had a higher frequency than controls (45% and 0%, respectively). Serum IL-6 and IL-8 levels were similar between patients with asymptomatic hyperuricemia (mean ± SD 69.7 ± 73.4 and 18.5 ± 25.6 pg/ml, respectively) and gout (mean ± SD 75.8 ± 47.6 and 24.4 ± 31.7 pg/ml, respectively), and higher than controls (mean ± SD 28.2 ± 17.6 and 7.4 ± 6.0 pg/ml, respectively). A similar distribution was observed for miR-155 levels in asymptomatic hyperuricemia, patients with gout, and controls (mean ± SD 0.22 ± 0.18, 0.20 ± 0.14, and 0.08 ± 0.04, respectively). Associations between morphostructural abnormalities suggestive of urate deposits (regardless of clinical diagnosis) and serum markers were assessed. Subjects with urate deposits had higher IL-6 (257.2 versus 47.0 pg/ml; P = 0.005), IL-8 (73.2 versus 12.0 pg/ml; P = 0.026), and miR-155 (0.21 versus 0.16; P = 0.015) levels than those without deposition findings. CONCLUSION: In individuals with chronic asymptomatic hyperuricemia, the presence of synovitis and double contour sign by US may represent a subclinical manifestation of monosodium urate crystal nucleation, capable of triggering inflammatory pathways (IL-6 and IL-8) and mechanisms of intercellular communication (miR-155), similar to what is observed in patients with gout.

Sonographic characterization of Hoffa's fat pad. A pilot study.

This study addresses a topic that was previously unaddressed in the literature: the normal sonographic appearance of the Hoffa's fat pad (HFP) in young, asymptomatic subjects. The aim of the study is to describe the sonoanatomical features of HFP, including its echostructure, echogenicity, elasticity, and vascularization, in subjects without knee pathology. Knees of healthy subjects were examined with grayscale ultrasound (US) to determine the sonographic characteristics of the HFP. Echogenicity was assessed by pixel intensity quantification. Vascularity was evaluated by color Doppler (CD) US. Elasticity of the adipose tissue was examined by sonoelastography. The absence of HFP pathology was confirmed clinically in all participants and by magnetic resonance imaging in randomly selected participants. Seventy-two knees from 36 subjects were assessed. The HFP presented a characteristic well-defined two-layered echostructure: the superficial adipose tissue was hypoechoic with respect to the nearby patellar tendon and contained septae, whereas the deeper layer was homogeneously hypoechoic and lacked connective tissue septae. Echogenicity differed between the superficial and deeper layers (the deeper layer was brighter), suggesting that the degree of acoustic impedance differed between layers. CD detected blood flow in 55.5% of HFPs. The superficial HFP layer presented greater elasticity than the deeper HFP layer (88.8 vs. 75.3 Kpa; p < .001). Our study provides a comprehensive description of the normal sonographic features of the HFP, which is useful to increase the potential of US for the discrimination of pathological findings involving this anatomical area.