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.

Hyperuricemia on Admission Predicts Short-Term Mortality due to Myocardial Infarction in a Population with High Prevalence of Cardiovascular Risk Factors.

BACKGROUND: National health surveys have revealed an outstandingly high prevalence of obesity, hypertension, and diabetes in Mexico. OBJECTIVE: To assess whether serum uric acid levels on admission may predict short-term mortality in patients with ST-segment elevation myocardial infarction in a population with an unusually high prevalence of classic cardiovascular risks. METHODS: A total of 795 ST-segment elevation myocardial infarction patients undergoing primary reperfusion therapy were classified as having normouricemia or hyperuricemia according to serum uric acid levels at admission, and the occurrence of mortality and major adverse cardiovascular events during coronary care unit stay was assessed. RESULTS: Patients with hyperuricemia (n = 291; mean age 61.2 ± 11.9 years; 74.8% males) were older, obese, hypertensive, and had a higher Killip class at admission than those with normouricemia (n = 504; mean age 57.6 ± 11.3 years; 88.9% males). Mortality rates were 1.7 and 0.7 cases/100 patients per day of coronary care unit stay in hyperuricemic and normouricemic patients, respectively. Comparatively, no association was observed for the occurrence of major adverse cardiovascular events. After multivariate adjustments, independent predictors for short-term mortality were only Killip class ≥ 2 (HR: 13.15; 95% CI: 5.29-29.85; p < 0.0001) and elevated serum uric acid levels (HR: 1.99; 95% CI: 1.08-3.66; p = 0.026). CONCLUSIONS: Hyperuricemia on admission remains associated with short-term mortality in ST-segment elevation myocardial infarction patients from a population with an unusually high prevalence of cardiovascular risk factors.

The Type of Trypanosoma Cruzi Strain (Native or Non-Native) Used as Substrate for Immunoassays Influences the Ability of Screening Asymptomatic Blood Donors.

BACKGROUND: The origin (native or non-native) of Trypanosoma cruzi strains used as substrate for immunoassays may influence their performance. OBJECTIVE: To assess the performance of an immunoassay based on a native T. cruzi strain compared to another based on non-native T. cruzi strains, in asymptomatic blood donors from Mexico. METHODS: Serum samples from a tertiary referral center were tested by both ELISA-INC9 (native) and Chagatest (non-native) assays. All reactive serum samples were further analyzed by indirect immunofluorescence. RESULTS: Sera from 1,098 asymptomatic blood donors were tested. A 4.3 and 0.7% serum reactivity prevalence was observed using ELISA-INC9 and Chagatest, respectively (kappa = 0.13; -0.11 to 0.38). Subsequently, indirect immunofluorescence analyses showed higher positivity in serum samples reactive by ELISA-INC9 compared to those reactive by Chagatest (79 vs. 62.5%; p < 0.001). Furthermore, out of the 47 positive samples by both ELISA-INC9 and indirect immunofluorescence, only four (8.5%) were reactive in Chagatest assay. Meanwhile, four (80%) out of the five positive samples by both Chagatest and indirect immunofluorescence were reactive using ELISA-INC9. CONCLUSION: Immunoassays based on a native T. cruzi strain perform better than those based on non-native strains, highlighting the need to develop and validate screening assays in accordance to endemic T. cruzi strains.