Efficacy and Tolerability of Celecoxib in the Treatment of Acute Gouty Arthritis: A Randomized Controlled Trial

Pathophysiology and Treatment of Gout Arthritis; including Gout Arthritis of Hip Joint: A Literature Review

Gout is triggered by the accumulation of uric acid in the body, leading to hyperuricemia. Genetic, metabolic, and environmental factors can influence this condition. Excessive uric acid buildup results in the formation of monosodium urate (MSU) crystals, which precipitate in specific areas of the body, including the joints, where they can cause symptoms of gout. While the acute and chronic symptoms of gout have been well-documented, diagnosis of gout affecting the hip joint poses significant challenges. The global incidence of gout, the most prevalent form of inflammatory arthritis, is on the rise. Evaluation of the clinical signs, laboratory results, and imaging results is generally required for diagnosis of gout in cases where MSU crystals have not been detected. Hyperuricemia is considered a primary cause of arthritis symptoms, and comprehensive guidelines for treatment are available. Therefore, the choice of medication is straightforward, and moderate effectiveness of treatment has been demonstrated. Gout is a chronic disease, requiring lifelong uric acid-lowering medications, thus application of a treatment strategy based on the target blood uric acid concentration is necessary. Consequently, cases of gout will likely be observed more frequently by hip surgeons in clinical scenarios in the future. The objective of this review is to provide an overview of the pathophysiology of gout and subsequently examine recent advances in diagnostic methods and therapeutic agents based on an understanding of its underlying mechanisms. In addition, literature on gout-related issues affecting the hip joint, providing a useful reference for hip surgeons is examined.

H. Ralph Schumacher

Dr Schumacher was a force in rheumatology for more than half a century through his multiple roles as a researcher, clinician, mentor, and educator. He is not likely to be soon forgotten by the rheumatology community; however, it is hoped that this chapter can provide a faithful recollection that will help bring his memory to life for some and that rings true to those who knew him and learned from him.

MiRNA-23a-5p is the biomarkers for gouty arthritis and promotes inflammation in rats of gouty arthritis via MyD88/NF-κB pathway by induction TLR2

Objectives

In this study, we aimed to examine the efficacy of micro ribonucleic acid (miRNA)-23a-5p in gouty arthritis and to investigate its possible mechanism.

Materials and methods

Gouty arthritis in rat was established by intraarticular injection of 0.2 mL monosodium urate crystal (20 mg/mL) inside knee joint cavity. THP-1 cell was induced using lipopolysaccharides (LPS) for in vitro model.

Results

Serum miRNA-23a-5p expression levels were increased in rats of gouty arthritis. However, overexpression of miRNA-23a-5p promoted inflammation and induced myeloid differential protein-88 (MyD88)/nuclear factor-kappa B (NF-κB) pathway by induction toll-like receptor-2 (TLR2) in vitro. The inhibition of TLR2 attenuated the pro-inflammation effects of miRNA-23a-5p in inflammation in in vitro model of gouty arthritis.

Conclusion

Our findings demonstrate that miRNA-23a-5p is a biomarker for gouty arthritis and promotes inflammation in rats of gouty arthritis via MyD88/NF-κB pathway by targeting TLR2.

Management and Cure of Gouty Arthritis

Gout is the most common inflammatory arthritis in the United States. Gouty arthritis is associated with significant morbidity and mortality and is the result of chronic hyperuricemia. Gout is effectively managed and potentially cured by decreasing the overall urate burden with serum urate-lowering therapy. When serum urate is maintained at less than 6.0 mg/dL, urate deposition is resolved, and gout can be cured. Unfortunately, because of less than optimal physician monitoring and dose escalation, many patients do not achieve these urate levels.

Gouty Arthropathy: Review of Clinical Manifestations and Treatment, with Emphasis on Imaging

Gout, a crystalline arthropathy caused by the deposition of monosodium urate crystals in the articular and periarticular soft tissues, is a frequent cause of painful arthropathy. Imaging has an important role in the initial evaluation as well as the treatment and follow up of gouty arthropathy. The imaging findings of gouty arthropathy on radiography, ultrasonography, computed tomography, dual energy computed tomography, and magnetic resonance imaging are described to include findings of the early, acute and chronic phases of gout. These findings include early monosodium urate deposits, osseous erosions, and tophi, which may involve periarticular tissues, tendons, and bursae. Treatment of gout includes non-steroidal anti-inflammatories, colchicine, glucocorticoids, interleukin-1 inhibitors, xanthine oxidase inhibitors, uricosuric drugs, and recombinant uricase. Imaging is critical in monitoring response to therapy; clinical management can be modulated based on imaging findings. This review article describes the current standard of care in imaging and treatment of gouty arthropathy.

2021 Asia-Pacific League of Associations for Rheumatology clinical practice guideline for treatment of gout

BACKGROUND

Gout is the most prevalent inflammatory arthritis in the Asia-Pacific region and worldwide. This clinical practice guideline (CPG) aims to provide recommendations based on systematically obtained evidence and values and preferences tailored to the unique needs of patients with gout and hyperuricemia in Asia, Australasia, and the Middle East. The target users of these guidelines are general practitioners and specialists, including rheumatologists, in these regions.

METHODS

Relevant clinical questions were formulated by the Steering Committee. Systematic reviews of evidence were done, and certainty of evidence was assessed using Grading of Recommendations Assessment, Development and Evaluation methodology. A multi-sectoral consensus panel formulated the final recommendations.

RESULTS

The Asia-Pacific League of Associations for Rheumatology Task Force developed this CPG for treatment of gout with 3 overarching principles and 22 recommendation statements that covered the treatment of asymptomatic hyperuricemia (2 statements), treatment of acute gout (4 statements), prophylaxis against gout flare when initiating urate-lowering therapy (3 statements), urate-lowering therapy (3 statements), treatment of chronic tophaceous gout (2 statements), treatment of complicated gout and non-responders (2 statements), treatment of gout with moderate to severe renal impairment (1 statement), and non-pharmacologic interventions (5 statements).

CONCLUSION

Recommendations for clinically relevant scenarios in the management of gout were formulated to guide physicians in administering individualized care.

Non-steroidal anti-inflammatory drugs for acute gout

BACKGROUND

Gout is an inflammatory arthritis resulting from the deposition of monosodium urate crystals in and around joints. Non-steroidal anti-inflammatory drugs (NSAIDs) are commonly used to treat acute gout. This is an update of a Cochrane Review first published in 2014.

OBJECTIVES

To assess the benefits and harms of non-steroidal anti-inflammatory drugs (NSAIDs) (including cyclo-oxygenase-2 (COX-2) inhibitors (COXIBs)) for acute gout.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, and Embase for studies to 28 August 2020. We applied no date or language restrictions.

SELECTION CRITERIA

We considered randomised controlled trials (RCTs) and quasi-RCTs comparing NSAIDs with placebo or another therapy for acute gout. Major outcomes were pain, inflammation, function, participant-reported global assessment, quality of life, withdrawals due to adverse events, and total adverse events.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures as expected by Cochrane.

MAIN RESULTS

We included in this update 28 trials (3406 participants), including 5 new trials. One trial (30 participants) compared NSAIDs to placebo, 6 (1244 participants) compared non-selective NSAIDs to selective cyclo-oxygenase-2 (COX-2) inhibitors (COXIBs), 5 (712 participants) compared NSAIDs to glucocorticoids, 13 compared one NSAID to another NSAID (633 participants), and single trials compared NSAIDs to rilonacept (225 participants), acupuncture (163 participants), and colchicine (399 participants). Most trials were at risk of selection, performance, and detection biases. We report numerical data for the primary comparison NSAIDs versus placebo and brief results for the two comparisons - NSAIDs versus COX-2 inhibitors and NSAIDs versus glucocorticoids. Low-certainty evidence (downgraded for bias and imprecision) from 1 trial (30 participants) shows NSAIDs compared to placebo. More participants (11/15) may have a 50% reduction in pain at 24 hours with NSAIDs than with placebo (4/15) (risk ratio (RR) 2.7, 95% confidence interval (CI) 1.1 to 6.7), with absolute improvement of 47% (3.5% more to 152.5% more). NSAIDs may have little to no effect on inflammation (swelling) after four days (13/15 participants taking NSAIDs versus 12/15 participants taking placebo; RR 1.1, 95% CI 0.8 to 1.5), with absolute improvement of 6.4% (16.8% fewer to 39.2% more). There may be little to no difference in function (4-point scale; 1 = complete resolution) at 24 hours (4/15 participants taking NSAIDs versus 1/15 participants taking placebo; RR 4.0, 95% CI 0.5 to 31.7), with absolute improvement of 20% (3.3% fewer to 204.9% more). NSAIDs may result in little to no difference in withdrawals due to adverse events (0 events in both groups) or in total adverse events; two adverse events (nausea and polyuria) were reported in the placebo group (RR 0.2, 95% CI 0.0, 3.8), with absolute difference of 10.7% more (13.2% fewer to 38% more). Treatment success and health-related quality of life were not measured. Moderate-certainty evidence (downgraded for bias) from 6 trials (1244 participants) shows non-selective NSAIDs compared to selective COX-2 inhibitors (COXIBs). Non-selective NSAIDs probably result in little to no difference in pain (mean difference (MD) 0.03, 95% CI 0.07 lower to 0.14 higher), swelling (MD 0.08, 95% CI 0.07 lower to 0.22 higher), treatment success (MD 0.08, 95% CI 0.04 lower to 0.2 higher), or quality of life (MD -0.2, 95% CI -6.7 to 6.3) compared to COXIBs. Low-certainty evidence (downgraded for bias and imprecision) suggests no difference in function (MD 0.04, 95% CI -0.17 to 0.25) between groups. Non-selective NSAIDs probably increase withdrawals due to adverse events (RR 2.3, 95% CI 1.3 to 4.1) and total adverse events (mainly gastrointestinal) (RR 1.9, 95% CI 1.4 to 2.8). Moderate-certainty evidence (downgraded for bias) based on 5 trials (712 participants) shows NSAIDs compared to glucocorticoids. NSAIDs probably result in little to no difference in pain (MD 0.1, 95% CI -2.7 to 3.0), inflammation (MD 0.3, 95% CI 0.07 to 0.6), function (MD -0.2, 95% CI -2.2 to 1.8), or treatment success (RR 0.9, 95% CI 0.7 to 1.2). There was no difference in withdrawals due to adverse events with NSAIDs compared to glucocorticoids (RR 2.8, 95% CI 0.5 to 14.2). There was a decrease in total adverse events with glucocorticoids compared to NSAIDs (RR 1.6, 95% CI 1.0 to 2.5).

AUTHORS' CONCLUSIONS

Low-certainty evidence from 1 placebo-controlled trial suggests that NSAIDs may improve pain at 24 hours and may have little to no effect on function, inflammation, or adverse events for treatment of acute gout. Moderate-certainty evidence shows that COXIBs and non-selective NSAIDs are probably equally beneficial with regards to improvement in pain, function, inflammation, and treatment success, although non-selective NSAIDs probably increase withdrawals due to adverse events and total adverse events. Moderate-certainty evidence shows that systemic glucocorticoids and NSAIDs probably are equally beneficial in terms of pain relief, improvement in function, and treatment success. Withdrawals due to adverse events were also similar between groups, but NSAIDs probably result in more total adverse events. Low-certainty evidence suggests no difference in inflammation between groups. Only low-certainty evidence was available for the comparisons NSAID versus rilonacept and NSAID versus acupuncture from single trials, or one NSAID versus another NSAID, which also included many NSAIDs that are no longer in clinical use. Although these data were insufficient to support firm conclusions, they do not conflict with clinical guideline recommendations based upon evidence from observational studies, findings for other inflammatory arthritis, and expert consensus, all of which support the use of NSAIDs for acute gout.

Pharmacotherapy for gout

Background: Gout is a common disease that is mainly caused by hyperuricemia. Although it is relatively easy to treat, adherence to drug treatment and the rate at which treatment targets are met is low.Current Concepts: For the treatment of acute gout attack, colchicine, nonsteroidal anti-inflammatory drugs, and glucocorticoids can be used alone or in combination depending on the severity of symptoms. To prevent gout attacks, patients are started on colchicine prior to or concurrent with treatment with uric acid–lowering drugs. The treatment is maintained until serum uric acid levels have returned to normal, and the patient has had no acute attacks for three to six months. Ultimately, the symptoms of gout are controlled in the long term by treating the patient’s hyperuricemia. For this purpose, allopurinol, febuxostat, and benzbromarone are used, and the side effects and contraindications for each drug should be checked. The goal for the treatment of chronic gout is to maintain a serum uric acid concentration below 6.0 mg/dL.Discussion and Conclusion: Patients visit the emergency departments of hospitals for sudden gout attacks. However, gout is a chronic disease that requires the lifelong use of uric acid–lowering agents. Therefore, it is necessary to educate patients on a serum urate-based treat-to-target approach.

Therapeutic approaches in the treatment of gout

Gout is a disease in which the metabolic condition hyperuricemia leads to the formation of monosodium urate crystals, which provoke acute and chronic inflammatory responses through activation of the innate immune system. Recent advances in our knowledge of gout pathogenesis have emphasized the role of the kidneys in urate handling, the evolutionary loss of uricase as a necessary precondition for hyperuricemia, and the central role of IL-1ß in the pathogenesis of gouty inflammation. These, and other advances, have shaped our current strategies for managing gout. Here, we review the most current, evidence-based gout management approaches, including treating acute flares, addressing gout through the long-term regulation of serum urate, and prophylaxis against gouty flares during urate lowering.

Efficacy and Safety of Pharmacologic Interventions in Patients Experiencing a Gout Flare: A Systematic Review and Network Meta-Analysis

OBJECTIVE

To compare the relative efficacy and safety of pharmacologic antiinflammatory interventions for gout flares.

METHODS

We searched Ovid Medline, Embase, and Cochrane library for randomized controlled trials (RCTs) that compared pharmacologic antiinflammatory treatment of gout flares. We conducted a network meta-analysis (NMA) using a frequentist framework and assessed the certainty of evidence and made conclusions using the Grading of Recommendations Assessment, Development, and Evaluation for NMA.

RESULTS

In the 30 eligible RCTs, canakinumab provided the highest pain reduction at day 2 and at longest follow-up (mean difference relative to acetic acid derivative nonsteroidal antiinflammatory drugs [NSAIDs] -41.12 [95% confidence interval (95% CI) -53.36, -29.11] on a 0-100 scale at day 2, and mean difference -12.84 [95% CI -20.76, -4.91] at longest follow-up; both moderate certainty; minimum important difference -19). Intravenous or intramuscular corticosteroids were inferior to canakinumab but may be better than the other commonly used interventions (low to very low certainty). For joint tenderness, canakinumab may be the most effective intervention at day 2. Acetic acid derivative NSAIDs improved joint swelling better than ibuprofen NSAIDs at day 2 (mean difference -0.29 [95% CI -0.56, -0.02] on a 0-4 scale; moderate certainty) and improved patient global assessment (PtGA) greater than ibuprofen NSAIDs at the longest follow-up (mean difference -0.44 [95% CI -0.86, -0.02]; moderate).

CONCLUSION

Canakinumab may be superior to other alternatives and intravenous or intramuscular corticosteroids may be the second best in pain reduction. Acetic acid derivative NSAIDs may be superior to ibuprofen NSAIDs in improving joint swelling and PtGA.

Management and Cure of Gouty Arthritis

Gout is the most common inflammatory arthritis in the United States. Gouty arthritis is associated with significant morbidity and mortality and is caused by hyperuricemia. Gout is effectively managed and potentially cured by decreasing the overall urate burden with serum urate-lowering therapy. When serum urate is maintained at less than 6.0 mg/dL urate deposition is resolved and gout can be cured. Unfortunately, owing to a lack of physician monitoring and dose escalation the majority of patients do not achieve these urate levels.

2020 American College of Rheumatology Guideline for the Management of Gout

OBJECTIVE

To provide guidance for the management of gout, including indications for and optimal use of urate-lowering therapy (ULT), treatment of gout flares, and lifestyle and other medication recommendations.

METHODS

Fifty-seven population, intervention, comparator, and outcomes questions were developed, followed by a systematic literature review, including network meta-analyses with ratings of the available evidence according to the Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology, and patient input. A group consensus process was used to compose the final recommendations and grade their strength as strong or conditional.

RESULTS

Forty-two recommendations (including 16 strong recommendations) were generated. Strong recommendations included initiation of ULT for all patients with tophaceous gout, radiographic damage due to gout, or frequent gout flares; allopurinol as the preferred first-line ULT, including for those with moderate-to-severe chronic kidney disease (CKD; stage >3); using a low starting dose of allopurinol (≤100 mg/day, and lower in CKD) or febuxostat (<40 mg/day); and a treat-to-target management strategy with ULT dose titration guided by serial serum urate (SU) measurements, with an SU target of <6 mg/dl. When initiating ULT, concomitant antiinflammatory prophylaxis therapy for a duration of at least 3-6 months was strongly recommended. For management of gout flares, colchicine, nonsteroidal antiinflammatory drugs, or glucocorticoids (oral, intraarticular, or intramuscular) were strongly recommended.

CONCLUSION

Using GRADE methodology and informed by a consensus process based on evidence from the current literature and patient preferences, this guideline provides direction for clinicians and patients making decisions on the management of gout.

2020 American College of Rheumatology Guideline for the Management of Gout

OBJECTIVE

To provide guidance for the management of gout, including indications for and optimal use of urate-lowering therapy (ULT), treatment of gout flares, and lifestyle and other medication recommendations.

METHODS

Fifty-seven population, intervention, comparator, and outcomes questions were developed, followed by a systematic literature review, including network meta-analyses with ratings of the available evidence according to the Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology, and patient input. A group consensus process was used to compose the final recommendations and grade their strength as strong or conditional.

RESULTS

Forty-two recommendations (including 16 strong recommendations) were generated. Strong recommendations included initiation of ULT for all patients with tophaceous gout, radiographic damage due to gout, or frequent gout flares; allopurinol as the preferred first-line ULT, including for those with moderate-to-severe chronic kidney disease (CKD; stage >3); using a low starting dose of allopurinol (≤100 mg/day, and lower in CKD) or febuxostat (<40 mg/day); and a treat-to-target management strategy with ULT dose titration guided by serial serum urate (SU) measurements, with an SU target of <6 mg/dl. When initiating ULT, concomitant antiinflammatory prophylaxis therapy for a duration of at least 3-6 months was strongly recommended. For management of gout flares, colchicine, nonsteroidal antiinflammatory drugs, or glucocorticoids (oral, intraarticular, or intramuscular) were strongly recommended.

CONCLUSION

Using GRADE methodology and informed by a consensus process based on evidence from the current literature and patient preferences, this guideline provides direction for clinicians and patients making decisions on the management of gout.

Gout: state of the art after a decade of developments

This review article summarizes the relevant English literature on gout from 2010 through April 2017. It emphasizes that the current epidemiology of gout indicates a rising prevalence worldwide, not only in Western countries but also in Southeast Asia, in close relationship with the obesity and metabolic syndrome epidemics. New pathogenic mechanisms of chronic hyperuricaemia focus on the gut (microbiota, ABCG2 expression) after the kidney. Cardiovascular and renal comorbidities are the key points to consider in terms of management. New imaging tools are available, including US with key features and dual-energy CT rendering it able to reveal deposits of urate crystals. These deposits are now included in new diagnostic and classification criteria. Overall, half of the patients with gout are readily treated with allopurinol, the recommended xanthine oxidase inhibitor (XOI), with prophylaxis for flares with low-dose daily colchicine. The main management issues are related to patient adherence, because gout patients have the lowest rate of medication possession ratio at 1 year, but they also include clinical inertia by physicians, meaning XOI dosage is not titrated according to regular serum uric acid level measurements for targeting serum uric acid levels for uncomplicated (6.0 mg/dl) and complicated gout, or the British Society for Rheumatology recommended target (5.0 mg/dl). Difficult-to-treat gout encompasses polyarticular flares, and mostly patients with comorbidities, renal or heart failure, leading to contraindications or side effects of standard-of-care drugs (colchicine, NSAIDs, oral steroids) for flares; and tophaceous and/or destructive arthropathies, leading to switching between XOIs (febuxostat) or to combining XOI and uricosurics.

How Would You Manage This Patient With Gout?: Grand Rounds Discussion From Beth Israel Deaconess Medical Center

Gout is the most common form of inflammatory arthritis. In 2012, the American College of Rheumatology (ACR) issued a guideline, which was followed in 2017 by one from the American College of Physicians (ACP). The guidelines agree on treating acute gout with a corticosteroid, nonsteroidal anti-inflammatory drug, or colchicine and on not initiating long-term urate-lowering therapy (ULT) for most patients after a first gout attack and in those whose attacks are infrequent (<2 per year). However, they differ on treatment of both recurrent gout and problematic gout. The ACR advocates a "treat-to-target" approach, and the ACP did not find enough evidence to support this approach and offered an alternative strategy that bases intensity of ULT on the goal of avoiding recurrent gout attacks ("treat-to-avoid-symptoms") with no monitoring of urate levels. They also disagree on the role of a gout-specific diet. Here, a general internist and a rheumatologist discuss these guidelines; they debate how they would manage an acute attack of gout, if and when to initiate ULT, and the goals for ULT. Lastly, they offer specific advice for a patient who is uncertain about whether to begin this therapy.

Treatment with Allopurinol is Associated with Lower Risk of Acute Kidney Injury in Patients with Gout: A Retrospective Analysis of a Nested Cohort

INTRODUCTION

Gout is characterized by recurrent episodes of acute inflammation of joint structures, called gout flares, and flares are commonly treated with nonsteroidal anti-inflammatory drugs (NSAIDs). The objective of the study was to evaluate risk factors associated with acute kidney injury (AKI) attributed to NSAIDs in a cohort of patients who were exposed to NSAIDs to treat gout flares prior to urate-lowering therapy.

METHODS

Retrospective analysis of a nested cohort of 983 gout patients in whom general variables (age, gender, renal function, ethanol intake, hypertension, hyperlipidemia, diabetes, vascular events, diuretic use) and also variables related to gout and severity of gout (serum urate levels, number for flares per year, presence of tophi, joint distribution, X-ray involvement, previous urate-lowering therapy) were available for analysis. Outcomes considered were loss of renal function attributed to NSAID prescription following the RIFLE classification for (risk, injury, and failure) for acute renal events. Variables associated with increased risk in Kaplan-Meier survival analysis were tested with multivariable Cox survival analysis, using time from onset of gout to the event as time exposed to NSAIDs.

RESULTS

Of 983 patients, 55 (5.6%) experienced AKI; the number of flares in the year previous to the renal event and polyarticular joint distribution were associated with higher risk of renal events. Other variables previously described in the literature, such as previous chronic renal disease, use of diuretics, and presence of previous vascular events, were also independently associated with increased risk of AKI. Interestingly, patients who had been previously prescribed allopurinol showed a lower risk of acute renal events.

CONCLUSION

In addition to classic risk factors, the number of flares and extensive joint distribution were associated with higher risk for renal injury in patients with gout, while previous prescription of allopurinol was associated with lower risk.

Current and future therapies for gout

INTRODUCTION

Gout is a common disease responsible for recurrent flares triggered by the deposition of monosodium urate crystals secondary to longstanding hyperuricaemia. The management of gout implies both the treatment of flares and the treatment of hyperuricaemia itself. Recent improvement in the understanding of the disease led to the development of new drugs. Areas covered: This review covers data related to 'old' treatments of flares and hyperuricaemia, evidence on the recently approved drugs and emerging therapies in development. Expert opinion: Recent data provide a good grasp of the optimal use of colchicine, corticosteroids and NSAIDs for the treatment of flares. Interleukin-1 blocking therapies have an increasing role in the management of difficult-to-treat gout. Sub-optimal use of allopurinol is common and its potency to reduce serum uric acid (SUA) levels is underestimated. Febuxostat effectively reduces SUA levels. New uricosurics, notably lesinurad and arhalofenate, in combination with xanthine oxidase inhibitors, offer promising perspectives to help a greater number of patients achieve sufficient SUA reduction.

2016 updated EULAR evidence-based recommendations for the management of gout

BACKGROUND

New drugs and new evidence concerning the use of established treatments have become available since the publication of the first European League Against Rheumatism (EULAR) recommendations for the management of gout, in 2006. This situation has prompted a systematic review and update of the 2006 recommendations.

METHODS

The EULAR task force consisted of 15 rheumatologists, 1 radiologist, 2 general practitioners, 1 research fellow, 2 patients and 3 experts in epidemiology/methodology from 12 European countries. A systematic review of the literature concerning all aspects of gout treatments was performed. Subsequently, recommendations were formulated by use of a Delphi consensus approach.

RESULTS

Three overarching principles and 11 key recommendations were generated. For the treatment of flare, colchicine, non-steroidal anti-inflammatory drugs (NSAIDs), oral or intra-articular steroids or a combination are recommended. In patients with frequent flare and contraindications to colchicine, NSAIDs and corticosteroids, an interleukin-1 blocker should be considered. In addition to education and a non-pharmacological management approach, urate-lowering therapy (ULT) should be considered from the first presentation of the disease, and serum uric acid (SUA) levels should be maintained at<6 mg/dL (360 µmol/L) and <5 mg/dL (300 µmol/L) in those with severe gout. Allopurinol is recommended as first-line ULT and its dosage should be adjusted according to renal function. If the SUA target cannot be achieved with allopurinol, then febuxostat, a uricosuric or combining a xanthine oxidase inhibitor with a uricosuric should be considered. For patients with refractory gout, pegloticase is recommended.

CONCLUSIONS

These recommendations aim to inform physicians and patients about the non-pharmacological and pharmacological treatments for gout and to provide the best strategies to achieve the predefined urate target to cure the disease.

Gout: optimizing treatment to achieve a disease cure

Gout is one of the most common inflammatory arthritides. The disease is due to the deposition of monosodium urate crystals. These deposits are reversible with proper treatment, suggesting that gout is a curable disease. The main aim in gout is to lower serum uric acid levels to a pre-established target; there are different urate-lowering drugs (xanthine oxidase inhibitors, uricosurics and uricases) through which this can be achieved. Proper treatment of gout also involves correct management of acute flares and their prevention. To ensure treatment adherence it is necessary to explain to the patient what the objectives are.

Activation of peripheral KCNQ channels relieves gout pain

Supplemental Digital Content is Available in the Text.

Combining electrophysiology and in vivo pain models, the concept that activation of peripheral KCNQ channels relieves the gout pain is demonstrated.

Intense inflammatory pain caused by urate crystals in joints and other tissues is a major symptom of gout. Among therapy drugs that lower urate, benzbromarone (BBR), an inhibitor of urate transporters, is widely used because it is well tolerated and highly effective. We demonstrate that BBR is also an activator of voltage-gated KCNQ potassium channels. In cultured recombinant cells, BBR exhibited significant potentiation effects on KCNQ channels comparable to previously reported classical activators. In native dorsal root ganglion neurons, BBR effectively overcame the suppression of KCNQ currents, and the resultant neuronal hyperexcitability caused by inflammatory mediators, such as bradykinin (BK). Benzbromarone consistently attenuates BK-, formalin-, or monosodium urate–induced inflammatory pain in rat and mouse models. Notably, the analgesic effects of BBR are largely mediated through peripheral and not through central KCNQ channels, an observation supported both by pharmacokinetic studies and in vivo experiments. Moreover, multiple residues in the superficial part of the voltage sensing domain of KCNQ channels were identified critical for the potentiation activity of BBR by a molecular determinant investigation. Our data indicate that activation of peripheral KCNQ channels mediates the pain relief effects of BBR, potentially providing a new strategy for the development of more effective therapies for gout.

Efficacy and safety of etoricoxib compared with NSAIDs in acute gout: a systematic review and a meta-analysis

The aim is to study the efficacy and safety of etoricoxib in the treatment of acute gout, as compared with non-steroidal anti-inflammatory drugs (NSAIDs). We conducted a computerized search of electronic databases: PubMed, EMBASE, Web of Science, China Biology Medicine disc, and Cochrane Library. The search terms were as follows: gout arthritis, tophus, etoricoxib, indometacin naproxen, diclofenac, and NSAIDs. Articles were searched from 1983 until August 2014. A manual search of peer-reviewed English documents was performed by cross-checking the bibliographies of selected studies. These trials reported pain relief as the primary outcome. Tenderness, swelling, patients' global assessments of response to treatment, and investigators' global assessments of response to treatment were reported as the secondary outcomes. All adverse events were recorded for safety assessment. Six trials including 851 patients were identified. Both etoricoxib and NSAIDs had an effect on inflammation and analgesia. Compared with indometacin and diclofenac, etoricoxib had a lower incidence of adverse events. Etoricoxib 120 mg administered orally once daily has the same efficacy on acute gout as indometacin and diclofenac. Etoricoxib is tolerated better by patients than NSAIDs such as indometacin and diclofenac.

In vitro evidence that phosphatidylcholine protects against indomethacin/bile acid-induced injury to cells

Indomethacin is a powerful analgesic nonsteroidal anti-inflammatory drug (NSAID), but is limited in use by its primary side effect to cause gastrointestinal bleeding and serious injury. One factor important for exacerbating NSAID injury is the presence of bile acids, which may interact with indomethacin to form toxic mixed micelles in the gut. The development of a safer gastrointestinal formulation of indomethacin that is chemically complexed with phosphatidylcholine (PC-indomethacin) may offer an improved therapeutic agent, particularly in the presence of bile acid, but its potential protective mechanism is incompletely understood. Intestinal epithelial cells (IEC-6) were tested for injury with indomethacin (alone and plus various bile acids) compared with PC-indomethacin (alone and plus bile acids). To explore a role for bile acid uptake into cells as a requirement for NSAID injury, studies were performed using Madin-Darby canine kidney cells transfected with the apical sodium-dependent bile acid transporter (ASBT). Indomethacin, but not PC-indomethacin, was directly and dose-dependently injurious to IEC-6 cells. Similarly, the combination of any bile acid plus indomethacin, but not PC-indomethacin, induced cell injury. The expression of ASBT had a modest effect on the acute cytotoxicity of indomethacin in the presence of some conjugated bile acids. Complexing PC with indomethacin protected against the acute intestinal epithelial injury caused by indomethacin regardless of the presence of bile acids. The presence of luminal bile acid, but not its carrier-mediated uptake into the enterocyte, is required for acute indomethacin-induced cell injury. It is likely that initial cell damage induced by indomethacin occurs at or near the cell membrane, an effect exacerbated by bile acids and attenuated by PC.

Non-steroidal anti-inflammatory drugs for acute gout

BACKGROUND

Gout is an inflammatory arthritis that is characterised by the deposition of monosodium urate crystals in synovial fluid and other tissues. The natural history of articular gout is generally characterised by three periods: asymptomatic hyperuricaemia, episodes of acute gout and chronic gouty arthritis. Non-steroidal anti-inflammatory drugs (NSAIDs) including selective cyclo-oxygenase-2 (COX-2) inhibitors (COXIBs) are commonly used to treat acute gout. Published guidelines recommend their use to treat acute attacks, using maximum recommended doses for a short time.

OBJECTIVES

To assess the benefit and safety of NSAIDs (including COXIBs) for acute gout.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE and EMBASE for studies to 7 October 2013, the 2010 and 2011 ACR and EULAR abstracts and performed a handsearch of reference lists of articles. We searched the World Health Organization (WHO) trial register and ClinicalTrials.gov. We applied no date or language restrictions.

SELECTION CRITERIA

We considered all published randomised controlled trials (RCTs) and quasi-randomised controlled clinical trials that compared NSAIDs with placebo or another therapy (including non-pharmacological therapies) for acute gout. Major outcomes were pain (proportion with 50% or more reduction in pain or mean pain when the dichotomous outcome was unavailable), inflammation (e.g. measured by joint swelling/erythema/tenderness), function of target joint, participant's global assessment of treatment success, health-related quality of life, withdrawals due to adverse events and total adverse events.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected the studies for inclusion, extracted the data, performed a risk of bias assessment and assessed the quality of the evidence using the GRADE approach.

MAIN RESULTS

We included 23 trials (2200 participants).One trial (30 participants) of low-quality evidence compared an NSAID (tenoxicam) with placebo. It found that significantly more participants had more than 50% reduction in pain after 24 hours (11/15 participants) compared with those taking placebo (4/15 participants) (risk ratio (RR) 2.75, 95% confidence interval (CI) 1.13 to 6.72). A similar outcome was seen for more than 50% improvement in joint swelling after 24 hours (5/15 participants taking NSAIDs versus 2/15 participants taking placebo; RR 2.50, 95% CI 0.57 to 10.93). The trial did not measure function, participant global assessment of treatment success and health-related quality of life. There were no adverse events reported with the use of tenoxicam; two adverse events (nausea and polypuria) were reported in the placebo group. No between-group differences in outcome were observed after four days.Moderate-quality evidence based upon four trials (974 participants) indicated that NSAIDs and COXIBs produced similar benefits in terms of pain, swelling and global improvement, but COXIBs were associated with fewer adverse events. Pain reduction was 1.9 points on a 0- to 10-point scale with COXIBs (0 was no pain) while pain reduction with NSAIDs was 0.03 points lower or better (mean difference (MD) -0.03, 95% CI -0.19 to 0.13). Joint swelling in the COXIB group was 1.64 points on a 0- to 3-point scale (0 is no swelling) and 0.13 points higher with NSAIDs (MD 0.13, 95% CI -0.08 to 0.34). Function was not reported. Participant-reported global assessment was 1.56 points on a 0- to 4-point scale with COXIBs (0 was the best score) and was 0.04 points higher with NSAIDs (MD 0.04, 95% CI -0.12 to 0.20). Health-related quality of life assessed using the 36-item Short Form showed no evidence of a statistically significant between-group difference (MD 0.49, 95% CI -1.61 to 2.60 for the physical component). There were significantly fewer withdrawals due to adverse events in participants treated with COXIBs (3%) compared with NSAIDs (8%) (RR 2.39, 95% CI 1.34 to 4.28). There was a significantly lower number of total adverse events in participants treated with COXIBs (38%) compared with NSAIDs (60%) (RR 1.56, 95% CI 1.30 to 1.86).There was moderate-quality evidence based on two trials (210 participants) that oral glucocorticoids did not differ in pain reduction, function or adverse events when compared with NSAIDs. Pain reduction was 9.5 on a 0- to 100-point scale with glucocorticoids, pain reduction with NSAIDs was 1.74 higher or worse (MD 1.74, 95% CI -1.44 to 4.92). The trials did not assess inflammation. Function measured as walking disability was 17.4 points on a 0- to 100-point scale with glucocorticoids, function with NSAIDs was 0.1 lower or better (MD -0.10, 95% CI -4.72 to 4.52). The trials did not measure participant-reported global assessment and health-related quality of life. There were no withdrawals due to adverse events. There was no evidence of a difference in total number of adverse events with glucocorticoids (31%) versus NSAIDs (49%) (RR 1.58, 95% CI 0.76 to 3.28).

AUTHORS' CONCLUSIONS

Limited evidence supported the use of NSAIDs in the treatment of acute gout. One placebo-controlled trial provided evidence of benefit at 24 hours and little or no harm. We downgraded the evidence due to potential selection and reporting biases, and imprecision. While these data were insufficient to draw firm conclusions, they did not conflict with clinical guideline recommendations based upon evidence from observational studies, other inflammatory arthritis and expert consensus, which support the use of NSAIDs in acute gout.Moderate-quality evidence suggested that selective COX-2 inhibitors and non-selective NSAIDs are probably equally beneficial although COX-2 inhibitors are likely to be associated with significantly fewer total and gastrointestinal adverse events. We downgraded the evidence due to an unclear risk of selection and reporting biases. Moderate-quality evidence indicated that systemic glucocorticoids and NSAIDs were also equally beneficial in terms of pain relief. There were no withdrawals due to adverse events and total adverse events were similar between groups. We downgraded the evidence due to unclear risk of selection and reporting bias. There was low-quality evidence that there was no difference in function. We downgraded the quality due to unclear risk of selection bias and imprecision.