Gout and risk of knee replacement for severe knee osteoarthritis in the Singapore Chinese Health Study

Advanced Erosive Gouty Arthropathy of the Knee

A 57-year-old male, with chronic bilateral knee pain and a history of poorly controlled hyperuricemia leading to gouty attacks, underwent orthopedic assessment. Radiographic and MRI findings confirmed chronic gouty arthropathy with erosive bony defects, the most significant on the right proximal tibia. Total knee arthroplasty (TKA) was performed without any complications, addressing the bony defect with cement and a semi-constrained prosthesis. However, a gouty attack led to prolonged wound discharge and periprosthetic infection postoperatively, prompting revision surgery with debridement, antibiotics, and implant retention (DAIR). Intraoperative cultures revealed methicillin-sensitive Staphylococcus aureus (MSSA). The treatment included vancomycin and rifampicin. Two years post-surgery, the patient walked pain-free with a knee range of motion of 0-90º. This report highlights the complexity of treating gout-related knee osteoarthritis, emphasizing early intervention to mitigate risks of extensive surgical procedures and infections.

Associations of Changes in Knee Hyaline Cartilage Composition Measured With Dual-Energy Computed Tomography in Gout, Aging and Osteoarthritis

OBJECTIVE

To characterize dual-energy computed tomography (DECT) changes depicting hyaline cartilage changes in gout patients with and without osteoarthritis (OA) and in comparators without gout.

DESIGN

Patients with suspected crystal-associated arthropathy were enrolled and underwent bilateral DECT scans of the knees. Standardized regions of interest were defined in the femorotibial hyaline cartilage. Five DECT parameters were obtained: CT numbers in Hounsfield units (HU) at 80 and 140 kV, the electron density (Rho), the effective atomic number (Zeff), and the dual-energy index (DEI). Zones were compared between patients with gout, with and without knee OA, and between patients with gout and comparators without gout, after adjustment for confounders.

RESULTS

A total of 113 patients with gout (mean age 63.5 ± 14.3 years) and 15 comparators without gout (mean age 75.8 ± 11.5 years) were included, n = 65 (51%) had knee OA, and 466 zones of hyaline cartilage were analyzed. Older age was associated with lower attenuations at 80 kV (P < 0.01) and 140 kV (P < 0.01), and with Rho (P < 0.01). OA was characterized by lower attenuation at 140 kV (P = 0.03), but the lower Rho was nonsignificant after adjustment for confounders. In gout, hyaline cartilage exhibited lower Rho values (adjusted P = 0.04). Multivariable coefficients of association with Rho were -0.21 [-0.38;-0.04] (P = 0.014) for age, -4.15 [-9.0;0.7] (P = 0.093) for OA and 0.73 [-0.1;1.56] (P = 0.085) for monosodium urate volume.

CONCLUSION

Gout was associated with DECT-detected changes in cartilage composition, similar to those observed in older patients, with some similarities and some differences to those seen in OA. These results suggest the possibility of potential DECT biomarkers of OA.

The Effects of Gout Following total Knee Arthroplasty: A Retrospective Analysis

BACKGROUND

The prevalence of gout is increasing along with the number of total knee arthroplasties (TKA) performed annually. The purpose of this study was to evaluate the incidence of gout following TKA in patients who had a previous history of gout and to determine if it is associated with an increased rate of postoperative joint complications.

METHODS

Patients who did and did not have a preoperative diagnosis of gout and underwent a primary TKA were identified from a national database. The gout patients were matched 1:1 to patients who did not have gout and rates of postoperative gout diagnoses within 2 years of surgery were compared. Complication rates at mean 1 and 2 years were then compared for both patient cohorts using multivariable logistic regressions. A total of 17,463 patients with a prior diagnosis of gout were matched with 17,463 controls.

RESULTS

There were 53.8% of patients who had previous gout and had a recurrence of gout within 2 years versus 3.6% of controls (Odds Ratios [OR]: 30.86). At mean 1-year, patients who had gout were significantly more likely to experience prosthetic joint infections (PJIs) and revision procedures. At mean 2 years, gout patients were at increased risk of prosthetic loosening, PJI, revision, and incision and debridement procedures.

CONCLUSION

This study suggests that patients who had a prior diagnosis of gout are significantly more likely to experience recurrent episodes of gout after TKA. Gout attacks after TKA are associated with an increase in the rate of joint complications.

LEVEL OF EVIDENCE

Level III.

Serum uric acid and knee osteoarthritis in community residents without gout: a longitudinal study

OBJECTIVES

Emerging evidence suggests a potential link between OA and gout; however, the association between serum uric acid (UA) itself and knee OA remains uncertain due to a lack of longitudinal studies. Here, we investigated the association between serum UA and knee OA according to cartilage status in elderly community residents without gout.

METHODS

In this longitudinal study, participants without a history of gout were recruited from among the Korean cohort of the Hallym Aging Study (n = 296 for radiography study and n = 223 for MRI study). Weight-bearing knee radiographs and 1.5-T MRI scans, along with blood collection for analysis of serum UA, were performed at baseline and after 3 years. The severity and structural progression of knee OA were evaluated using the Kellgren-Lawrence grading system and the Whole-Organ MRI Score (WORMS) cartilage scoring method. Multivariable logistic regression analysis was conducted using generalized estimating equation (GEE) models.

RESULTS

Serum UA levels were not associated with radiographic progression after adjusting for age, sex and BMI. There was no significant association between serum UA and tibiofemoral cartilage loss on MRI. However, baseline serum UA levels were negatively associated with patellofemoral cartilage loss over 3 years (adjusted odd ratio 0.70 per 1 mg/dl increase, 95% CI: 0.49, 0.98).

CONCLUSION

In this population-based cohort, serum UA was not a risk factor for knee OA progression. Further large-scale longitudinal studies in other populations are needed to validate the effects of UA on cartilage damage.

The efficacy and tolerability of febuxostat treatment in a cohort of Chinese Han population with history of gout

Objective

To measure the effect of febuxostat on the serum levels of uric acid (sUA) and the proinflammatory cytokines interleukin (IL)-6, IL-17 and tumour necrosis factor-α (TNF-α) in Chinese Han patients with gout and hyperuricaemia.

Methods

This randomized, double-blind, placebo-controlled pilot study enrolled patients with gout and hyperuricaemia (sUA ≥ 8 mg/dl). Patients were randomized to receive either febuxostat 80 mg or placebo once daily for 24 weeks. The serum levels of sUA, IL-6, IL-17 and TNF-α were measured at weeks 0 (baseline), 2, 4, 8, 12, 16 and 24. Baseline clinical and demographic characteristics were recorded for all patients.

Results

A total of 156 patients were randomized: placebo group (n = 78) and febuxostat group (n = 78). The febuxostat group showed a significantly greater reduction in sUA compared with the placebo group. Serum uric acid concentration was reduced below 8 mg/dl in 46 of 61 patients (75.4%) by week 24. There were also reductions in the serum levels IL-6, IL-17 and TNF-α in the febuxostat group. In the febuxostat group, 10 of 78 patients (12.82%) discontinued treatment due to adverse drug reactions.

Conclusion

Febuxostat reduced the levels of sUA, TNF-α, IL-6 and IL-17, but there were some side-effects.

Gout in primary total knee arthroplasty: Prevalent but not independently associated with complications

BACKGROUND

Gout is a common synovial pathology, but its prevalence in patients undergoing total knee arthroplasty (TKA) and potential association with complications such as periprosthetic infection (PJI) and revision are unknown.

METHODS

Medicare data from 2009 to 2013 was retrospectively reviewed using PearlDiver. All patients 65 years of age or older and undergoing primary TKA with at least 3 years of pre-TKA records were included. The prevalence of gout was based on ICD-9 codes. Univariable associations of gout with PJI and revision at 1 year were assessed using odds ratios with 95% confidence intrervals (C.I.). To control for potential confounding, patients with a history of gout were matched on age, gender, smoking history, and Elixhauser Comorbidity Index (ECI) to patients without gout and associations reassessed.

RESULTS

The prevalence of gout in Medicare patients undergoing primary TKA was 5.7%. On univariable analysis, patients with a history of gout were more likely to develop PJI (O.R., 1.58; 95% C.I., 1.45-1.72) and undergo revision (O.R., 1.33; 95% C.I., 1.25-1.41) at 1 year. After matching for confounders, a history of gout was no longer associated with developing PJI (O.R., 0.98; 95% C.I., 0.90-1.06) or undergoing revision (O.R., 0.94; 95% C.I., 0.89-1.00) at 1 year.

CONCLUSIONS

Gout is a relatively common pathology in patients undergoing TKA. While gout is associated with increased complications, this appears to be driven by confounding through its association with other medical comorbidities. Gout does not appear to be an independent risk factor for complications following TKA.

Association between hyperuricemia, gout, urate lowering therapy, and osteoarthritis: A protocol for a systematic review and meta-analysis

INTRODUCTION

Osteoarthritis (OA), a chronic and degenerative joint disease characterized by articular cartilage degeneration, sclerosis of subchondral bone, and osteophyte formation, is deemed a leading cause of activity limitation and disability among the elderly people. Serum uric acid (UA) is a terminal metabolite of purine compound, while hyperuricemia (HU) and UA crystals are recognized causes of gout. Several studies have investigated the correlations between HU, gout and OA, but the findings are inconclusive. We are also concerned whether the urate lowering therapy (ULT) can become a potential treatment for OA and intend to undertake this meta-analysis to clarify the related hypotheses.

METHODS

Systematic literature search will be conducted on PubMed, Embase, and Web of Science to identify relevant studies up to February 2020 using appropriate search strategies. All citations and abstracts retrieved from literature search will be assessed by two reviewers independently. The Newcastle-Ottawa Scale or the Cochrane risk of bias assessment tool will be used as appropriate to assess the quality and the risk of bias of the included studies. The heterogeneity and the publication bias of the studies will be investigated accordingly.

RESULTS

We propose to undertake this meta-analysis as a feasible approach to clarify the associations between HU, gout or ULT, and OA.

DISCUSSIONS

This meta-analysis will help to strengthen our knowledge of the pathogenesis of OA and promote the development of preventive or treatment strategies.

REGISTRATION

PROSPERO registration number CRD42020168769.

Urate and osteoarthritis: Evidence for a reciprocal relationship

Hyperuricemia is a common condition, and in a subset of patients leads to gout, the most common inflammatory arthritis. Osteoarthritis is the most common form of arthritis overall, and gout and osteoarthritis frequently coexist in the same patient. However, the relationship between the two remains poorly defined. More particularly, the impact of osteoarthritis on the development of gout, and the impact of gout on the development of osteoarthritis, remain to be determined. Additionally, whether hyperuricemia mediates osteoarthritis in the absence of gout is uncertain. Here, we review the evidence linking gout and osteoarthritis, with a special focus on the role of hyperuricemia in the presence or absence of gout. Since disease modifying agents are currently available for hyperuricemia and gout but not for osteoarthritis, a contributory role for urate in the pathogenesis of osteoarthritis could have important clinical implications.

The association between asymptomatic hyperuricemia and knee osteoarthritis: data from the third National Health and Nutrition Examination Survey

OBJECTIVE

In vitro and clinical studies suggest that urate may contribute to osteoarthritis (OA) risk. We tested the associations between hyperuricemia and knee OA, and examined the role of obesity, using a cross-sectional, nationally representative dataset.

METHOD

National Health and Nutrition Examination Survey (NHANES) III used a multistage, stratified probability cluster design to select USA civilians from 1988 to 1994. Using NHANES III we studied adults >60 years, with or without hyperuricemia (serum urate > 6.8 mg/dL), excluding individuals with gout (i.e., limiting to asymptomatic hyperuricemia (AH)). Radiographic knee OA (RKOA) was defined as Kellgren-Lawrence grade ≥ 2 in any knee, and symptomatic radiographic knee osteoarthritis (RKOA) (sRKOA) was defined as RKOA plus knee pain (most days for 6 weeks) in the same knee.

RESULTS

AH prevalence was 17.9% (confidence interval (CI) 15.3-20.5). RKOA prevalence was 37.7% overall (CI 35.0-40.3), and was 44.0% for AH vs 36.3% for normouricemic adults (p = 0.056). symptomatic radiographic knee osteoarthritis (sRKOA) was more prevalent in AH vs normouricemic adults (17.4% vs 10.9%, p = 0.046). In multivariate models adjusting for obesity, model-based associations between AH and knee OA were attenuated (for RKOA, prevalence ratio (PR) = 1.14, 95% CI 0.95, 1.36; for sRKOA, PR = 1.40, 95% CI 0.98, 2.01). In stratified multivariate analyses, AH was associated with sRKOA in adults without obesity (PR = 1.66, 95% CI 1.02, 2.71) but not adults with obesity (PR = 1.21, 95% CI 0.66, 2.23).

CONCLUSIONS

Among adults aged 60 or older, AH is associated with knee OA risk that is more apparent in adults without obesity.

Common gene variants interactions related to uric acid transport are associated with knee osteoarthritis susceptibility

BACKGROUND

The presence of genetic variants in uric acid (UA) transporters can be associated with hyperuricemia, and therefore with an increased risk of monosodium urate (MSU) crystal precipitation. The inflammatory process triggered by these crystals leads to cartilage damage, which, in turn, could promote knee osteoarthritis (KOA).

OBJECTIVE

To determine whether genetic polymorphisms of the UA transporters and their interactions are associated with KOA.

MATERIALS AND METHODS

Two hundred forty-three unrelated Mexican-mestizo individuals were recruited for this case-control study. Ninety-three of them were KOA patients but without gout, and one hundred and fifty healthy individuals with no symptoms or signs of KOA were recruited as controls. Forty-one single-nucleotide polymorphisms (SNPs) involved in the UA transporters were genotyped with OpenArray technology in a QuantStudio 12K flex-System with both cases and controls.

RESULTS

After adjusting by age, gender, BMI, and ancestry, significant associations were found for eight SNPs: rs1260326 (GCKR), rs780093 (GCKR), rs17050272 (INHBB), rs1471633 (PDZK1), rs12129861 (PDZK1), rs7193778 (IGF1R), rs17786744 (STC1), and rs1106766 (R3HDM2). With respect to gene-gene interactions, the pairwise interactions of rs112129861 (PDZK1) and rs7193778 (IGF1R); rs17050272 (INHBB) and rs1106766 (R3HDM2); rs1106766 (R3HDM2) and rs780093 (GCKR); rs1260326 (GCKR) and rs17786744 (STC1); and rs17786744 (STC1) and rs1106766 (R3HDM2) make it possible to visualize the synergistic or antagonistic effect of their genotypes or alleles on KOA development.

CONCLUSIONS

Our preliminary results show that the common gene variants related to UA transport are associated with KOA in the Mexican population. Further studies must be carried out to corroborate it.

Consistency of the Sonographic Image (Double Contour Sign) in Patients with Gout after Ambulation

The aim of this study was to know whether or not any crystal shedding occurs after ambulation in patients with gout and how it affects the consistency of the sonographic image of crystal deposition on hyaline cartilage. A total of 18 consecutive patients (29 knees), 11 with early gout (17 knees) and seven with chondrocalcinosis (12 knees), were prospectively scanned by ultrasound. Examination at rest and after ambulation was performed in each patient. Crystal aggregates were measured in a transverse view. Crystal shedding after ambulation was noted in two patients (two knees) with gout. However, crystal deposits on the surface of the articular cartilage in gout kept invariable size. In patients with chondrocalcinosis, crystal shedding by ambulation was absent. The conclusion of this study is that the size of crystal deposits on the hyaline cartilage in gout and chondrocalcinosis assessed by ultrasound is not modifiable by ambulation.

Gout and healthcare utilization and complications after hip arthroplasty: a cohort study using the US National Inpatient Sample (NIS)

Little is known about the effect of gout on in-hospital complications and healthcare utilization after total hip arthroplasty (THA). We used the 1998-2014 U.S. National Inpatient Sample (NIS) to examine this question using cohort study design. Multivariable-adjusted Cox regression analyses included age, race, gender, underlying diagnosis, Deyo-Romano comorbidity index, insurance payer, and income. In adjusted analyses, we found that gout was associated with 9-20% higher healthcare utilization and 6% higher hazard of transfusion after primary THA. These findings can inform surgeons and patients of gout-associated complications post-THA.

Utility of Serological Markers for Detecting Persistent Infection in Two-Stage Revision Arthroplasty in Patients With Inflammatory Arthritis

BACKGROUND

Serum erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) are commonly used for the diagnosis of persistence of infection after the first stage of 2-stage revision arthroplasty for periprosthetic joint infection (PJI). As both ESR and CRP are markers of systemic inflammation, the utility of these tests to monitor infection clearance in patients with inflammatory arthritis is unclear.

METHODS

From 2001 to 2016, 44 two-stage revision total hip or knee arthroplasties in patients with an inflammatory arthritis diagnosed by a rheumatologist were identified. Persistence of infection at the time of planned second stage was defined as satisfying the Musculoskeletal Infection Society criteria for PJI (14 infected, 30 noninfected). ESR and CRP values were compared between the stages using nonparametric tests. Receiver operating characteristic analysis was performed to obtain the diagnostic parameters.

RESULTS

ESR and CRP decreased between the stages in the noninfected group (ESR: mean decrease = 31.6 mm/h [19.2-44.0], P < .001; CRP: mean decrease = 5.2 mg/dL [2.1-8.2], P < .001), but remained elevated in the infected group (ESR: mean decrease = 7.7 [-23.1 to 36.6], P = .572; CRP: mean decrease = 1.5 [-2.2 to 5.1], P = .258). Optimal thresholds for persistent infection were 29.5 mm/h and 2.8 mg/dL, respectively, for ESR and CRP. The sensitivity and specificity at the optimal thresholds were 64% and 77% for ESR, and 64% and 90% for CRP.

CONCLUSION

ESR and CRP responded to the treatment of PJI in patients with inflammatory arthritis and had reasonably high specificities with moderate sensitivities. ESR and CRP appear to be useful tools in diagnosing persistent infection even in patients with inflammatory arthritis.

Diagnostic Utility of Histological Analysis for Detecting Ongoing Infection During Two-Stage Revision Arthroplasty in Patients With Inflammatory Arthritis

BACKGROUND

Surgeons often rely on intra-operative histology (frozen sections [FS]) to determine the next step in surgical management during the second stage (re-implantation surgery) of 2-stage revision arthroplasty. The purpose of the study is to assess the accuracy of permanent sections (PS) and FS in the diagnosis of persistent infection during re-implantation in patients with an inflammatory arthritis.

METHODS

From 2001 to 2016, 47 planned second-stage revision total hip arthroplasty and total knee arthroplasty in patients with inflammatory arthritis were identified. Revisions were classified as having persistent infection if they were Musculoskeletal Infection Society positive at the time of second stage. PS or FS was considered to be positive for infection when at least one of the specimens demonstrated an acute inflammation. Receiver operating characteristic analysis was performed to obtain the diagnostic parameters.

RESULTS

There were 9 (19%) persistent infections. Both PS and FS had very high specificity (PS = FS = 94.7%). Sensitivity of PS was higher than FS, although not statistically significant (PS = 88.9%, FS = 55.6%, P = .083). Overall, PS had a better diagnostic utility than FS (area under the curve: PS vs FS = 0.92 vs 0.75, P = .045). Four specimens had discrepancies between PS and FS histology. In all 4 instances, the specimens were read as positive (infected) by PS, but negative by FS.

CONCLUSION

Histological analysis is recommended at the time of re-implantation surgery even in patients with inflammatory arthritis. PS had a better diagnostic utility than FS suggesting that areas of acute inflammation may be scattered and may not always be captured in the specimens taken for FS.

Exploring the Link between Uric Acid and Osteoarthritis

Both gout and osteoarthritis (OA) are common forms of arthritis that inflict a huge burden to an aging population with the increasing prevalence of obesity. Clinicians have long observed the link between these two conditions. In this review, we summarize the evidence from epidemiologic and immunological studies that described the possible relationship between the two conditions. The recent new understanding on monosodium uric acid crystal-induced inflammation has given insight into probable shared pathogenesis pathways for both conditions. We describe the potential therapeutic implications, particularly regarding the possibility of repurposing traditional gout medications for use in OA.