Excellent response to the clinical treatment of tophaceous gout

Limited Knee-Joint Range of Motion in Patients With Tophaceous Gout Improved With Medical Treatment: A 18-Months Follow Up

Objectives: Tophi may occur within the knee joint causing limited knee-joint range of motion (knee motion). We investigated the relationships between knee motion, total intra-articular tophi size (tIA-tophi), and total subcutaneous tophi size (tSC-tophi) and determined knee motion improvement after continual urate-lowering therapy (ULT). Methods: A total of 26 patients with tophaceous gout and limited knee motion were enrolled. Inclusion criteria were age ≤ 60 years and preserved knee joint space on a plain radiograph. tSC-tophi were measured using a Vernier caliper and tIA-tophi were measured using magnetic resonance imaging software. All patients were re-evaluated after 12-24 months of continual ULT. Upon initial visit, knee motion was related to tIA-tophi and tSC-tophi. Results: After an average of 18.2 months of ULT, the reduction in tSC-tophi was correlated with the reduction in tIA-tophi (P = 0.014, r = 0.395) and improvement in knee motion (P = 0.038, r = 0.408). Knee motion can be eventually improved even in cases of poor initial knee motion (P = 0.000, r = -0.911) or large initial tIA-tophi (P = 0.014, r = 0.476). Tophi can occur in any location within the knee joint. In multiple lineal regression, knee motion was predicted to improve 8.39° for every 10cm of tIA-tophi reduction. Conclusions: Limited knee motion in patients with intra-articular tophi improved with medical treatment, regardless of initial severity. Furthermore, tSC-tophi can be used as an indicator of limited knee motion and their improvement as a predictor of knee motion improvement.

Recent pharmacological advances in the management of gout

Gout is the most common cause of inflammatory arthritis worldwide, and reports show that despite availability of therapies, management is still suboptimal. The new EULAR 2016 recommendations for the treatment of gout highlight the huge development in gout therapies, and the number of drugs being trialled only continues to increase. A clinical review of the evidence that underlies the recommendations from EULAR can reveal possible gaps in the literature and avenues for future research into gout therapies.

Interventions for tophi in gout

BACKGROUND

Tophi develop in untreated or uncontrolled gout. Their presence can lead to severe and potentially fatal complications. To date there have been no systematic reviews focused on the management of tophi in gout.

OBJECTIVES

To assess the benefits and harms of non-surgical and surgical treatments for the management of tophi in gout.

SEARCH METHODS

We searched three databases: the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE. We handsearched American College of Rheumatology (ACR) and European League against Rheumatism (EULAR) abstracts from 2010 to 2011, references from included studies and trial registries. We completed the most recent search on 20 May 2013.

SELECTION CRITERIA

All published randomised controlled trials (RCTs) or controlled clinical trials with quasi-randomised methods of allocating participants to treatment examining interventions for tophi in gout in adults. Possible interventions included urate-lowering pharmacological treatment (e.g. benzbromarone, probenecid, allopurinol, febuxostat, pegloticase), surgical removal or other interventions such as haemodialysis.

DATA COLLECTION AND ANALYSIS

Two review authors extracted data from titles, abstracts and selected studies for detailed review, and extracted data and risk of bias independently. Major outcomes were number of participants with complete resolution of tophi, number of study participant withdrawals due to adverse events, joint pain reduction, function, quality of life, serum urate normalisation and total adverse events.

MAIN RESULTS

Only one study, at low risk of all biases, met the inclusion criteria. This was the pooled results from two RCTs (225 participants, 145 with tophi at baseline) randomised to one of three arms; pegloticase infusion every two weeks (biweekly), monthly pegloticase infusion (pegloticase infusion alternating with placebo infusion every two weeks) and placebo. Moderate-quality evidence from one study indicated that biweekly pegloticase 8 mg infusion reduced tophi in the subset of participants with tophi, but increased withdrawals due to adverse events in all participants, and monthly infusion appeared to result in less benefit.Biweekly pegloticase treatment resulted in resolution of tophi in 21/52 participants compared with 2/27 who received placebo (risk ratio (RR) 5.45, 95% confidence intervals (CI) 1.38 to 21.54; number needed to treat for an additional beneficial outcome (NNTB) 3 (95% CI 2 to 6).Eleven of 52 participants with monthly pegloticase treatment had complete resolution of one or more tophi compared with 2/27 who received placebo (RR 2.86, 95% CI 0.68 to 11.97).Participant-reported pain relief of 30% or greater, function, quality of life, serum urate normalisation, were reported for all participants but not separately for those with tophi; therefore, we did not include the results.Pegloticase administered biweekly resulted in more withdrawals due to adverse events compared with placebo (15/85 participants with pegloticase versus 1/43 participants with placebo; RR 7.59, 95% CI 1.04 to 55.55; number needed to treat for an additional harmful outcome (NNTH) 7, 95% CI 4 to 17). Pegloticase administered monthly also resulted in more withdrawals due to adverse events than placebo (16/84 participants with pegloticase versus 1/43 participants with placebo; RR 8.19, 95% CI 1.12 to 59.71; NNTH 6, 95% CI 4 to 14). Most withdrawals were due to infusion reactions.Total adverse events were high in all treatment groups: 80/85 participants administered pegloticase biweekly reported an adverse event compared with 41/43 from the placebo group (RR 0.99, 95% CI 0.91 to 1.07); 84/84 participants administered pegloticase monthly reported an adverse event versus 41/43 in the placebo group (RR 1.05, 95% CI 0.98 to 1.14). As 80% of adverse events were due to flares of gout, probably unrelated to the drug treatment per se, this may explain the high rate of adverse events in the placebo group - who were essentially untreated.

AUTHORS' CONCLUSIONS

This study showed pegloticase is probably beneficial in the management of tophi in gout, in terms of resolution of tophi, but with a high risk of adverse infusion reactions. However, there is a need for more RCT data considering other interventions, including surgical removal of tophi.