International rheumatology guidelines advocate a treat to serum urate target (T2T) approach for gout management. While individual studies have reported regional and national-level gout management, global patterns in gout care have not been synthesized. This study aimed to systematically review and meta-analyze global T2T care for patients with gout. Electronic databases were searched for studies reporting medication and serum urate testing in patients with gout. Meta-analyses were conducted to determine the pooled proportion of patients with gout achieving pre-specified T2T indicators. Sixty-seven papers were included from North America (n = 31 studies), Europe (n = 22), Oceania (n = 7), Asia (n = 6), and reporting data from multiple continents (n = 1). The global pooled percentages (95% confidence interval (CI)) of patients with gout achieving T2T indicators were: 52% (45%, 59%) on urate lowering therapy (ULT), 50% (40%, 61%) on ULT receiving regular uninterrupted ULT, 53% (40%, 65%) on ULT having any serum urate testing, and 34% (28%, 41%) on ULT achieving a serum urate target. Outside North America and Europe, there are relatively few studies about T2T care for gout management. However, available data demonstrate that a minority of people with gout receive T2T care worldwide. For those prescribed ULT, there are low rates of continuous therapy, serum urate testing, and achievement of serum urate target.

Background: Ankylosing spondylitis (AS) is a chronic inflammatory rheumatic disease affecting the axial skeleton and peripheral joints. The etiology of this disease remains poorly understood, but interactions between genetic and environmental factors have been implicated. The present study identified differentially expressed proteins in the synovial fluid (SF) of AS patients to elucidate the underlying cause of AS. Methods: A cohort of 40 SF samples from 10 AS and 10 each of rheumatoid arthritis (RA), gout, and osteoarthritis (OA) patients were analyzed by liquid chromatography tandem mass spectrometry (LC–MS/MS) to identify differentially expressed proteins specific to AS. The label-free LC–MS/MS results were verified by western blotting. Results: We identified 8 proteins that were > 1.5-fold upregulated in the SF of AS patients compared to that of the disease control groups, including HP, MMP1, MMP3, serum amyloid P-component (APCS), complement factor H-related protein 5 (CFHR5), mannose-binding lectin 2 (MBL2), complement component C9 (C9), and complement C4-A (C4A). CFHR5 and C9 were previously found in serum from AS patients, while APCS was previously found in SF as well as in serum. However, the present study has identified C4A, and MBL2 as potential AS biomarkers for the first time. The expression levels of MMP3, C9, and CFHR5 were verified in AS SF using western blotting. Conclusion: We performed quantitative comparative proteomic analysis using by LC–MS/MS of the SF from four disease states: RA, gout, and OA. This systematic comparison revealed novel differentially expressed proteins in AS SF, as well as two previously reported candidate biomarkers. We further verified the expression of MMP3, C9 and CFHR5 by western blot. These proteins may serve as diagnostic or prognostic biomarkers in patients with AS, and may thus improve the clinical outcomes of this serious disease.

Kim SH, et al. J Korean Med Sci. 2015 May;30(5):552-558. https://doi.org/10.3346/jkms.2015.30.5.552

The safety and efficacy of febuxostat in patients with stage 4-5 chronic kidney disease (CKD) are still unclear owing to a lack of studies in these patients. Therefore, we aimed to evaluate the effect of febuxostat on renal function, general safety, and efficacy in gout patients with stage 4-5 CKD. Among 739 patients who had been administered febuxostat from May 2012 to December 2016 at a single hospital in Korea, 370 patients who had been monitored for 1 year were analyzed. Serum uric acid levels and estimated glomerular filtration rate (eGFR) of patients with gouty arthritis were collected at baseline and 1 year after febuxostat administration. Among the 370 patients, 280 patients were stage 1-3 CKD, 63 patients were stage 4-5 CKD, and 27 patients were on dialysis. The eGFR of 63 patients with stage 4-5 CKD, excluding dialysis patients, was 19.84 ± 7.08 mL/min/1.73 m2 when they began to take febuxostat and 23.49 ± 16.67 mL/min/1.73 m2 after 12 months (p = 0.13). The urate-lowering effect after 12 months of febuxostat medication showed statistical significance (8.96 ± 2.31 mg/dL at baseline and 4.88 ± 1.68 mg/dL after 12 months, p < 0.01). The difference in incidence of adverse events among patients with stage 1-3 CKD, those with stage 4-5 CKD, and those on dialysis was not significant. Febuxostat demonstrated renal safety and good urate-lowering efficacy in gout patients with stage 4-5 CKD, who are not yet on dialysis.

Son CN, et al. J Korean Med Sci. 2014 Aug;29(8):1090-1093. https://doi.org/10.3346/jkms.2014.29.8.1090