Pseudotumor of gout in the patella of a kidney transplant recipient

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.

The broad spectrum of urate crystal deposition: unusual presentations of gouty tophi

OBJECTIVES

Gout is typically described as an inflammatory arthropathy that affects the peripheral joints. Our aim was to describe atypical and rare clinical presentations of gouty tophi to help increase physician awareness and aid in patient care.

METHODS

The relevant English literature of unusual gout manifestations was searched using the keywords gout, toph*, monosodium urate, uric acid, unusual, and rare. Well-described case reports, case series, and review articles were evaluated and included, if relevant, in the literature review.

RESULTS

Review of the literature revealed many unusual manifestations of gouty tophi involving the head and neck, skin, viscera, bones, tendons, ligaments, nerves, and axial skeleton. Transplant recipients, women, and elderly people are particularly susceptible to developing tophi. Furthermore, gout can cause diagnostic dilemmas, as it can be a great mimicker of and can coexist with infection, malignancy, and other connective tissue diseases. Imaging modalities can help detect tophi in atypical locations.

CONCLUSIONS

Tophi can present in unexpected locations, even as the first sign of gout, and vigilance is required when unusual symptoms or signs occur in a patient with gout.

Mimicry in older patients: tophaceous pseudogout as a tumorlike lesion: a case report

Pseudogout is frequently seen in painful arthritis of larger joints, especially the knees and shoulders. This case report describes a rare clinical entity of soft-tissue calcium pyrophosphate dihydrate crystal deposition disease surrounding the second metatarsal bone of an 81-year-old man with moderate painful swelling of the right forefoot for 2 years. Diagnostic imaging demonstrated a calcified soft-tissue tumor adjacent to the second metatarsal bone by considering a neoplastic process in the differential diagnosis. Excisional biopsy revealed a chalklike material on the calcified soft tissue that was pathognomonic for chondrocalcinosis or pseudogout. The excisional biopsy findings led to stagnation of the clinical symptoms, and no recurrence of the initial tumor was seen during 12-month follow-up. In the literature, only 28 cases of tophaceous pseudogout tumors in the extremities have been described. In these cases, the lesions were suspected of being chondrosarcomas. For this reason, a correct diagnosis has to be pursued by performing a biopsy to treat the disease correctly.

Utility of synovial biopsy

Synovial biopsies, gained either by blind needle biopsy or minimally invasive arthroscopy, offer additional information in certain clinical situations where routine assessment has not permitted a certain diagnosis. In research settings, synovial histology and modern applications of molecular biology increase our insight into pathogenesis and enable responses to treatment with new therapeutic agents to be assessed directly at the pathophysiological level. This review focuses on the diagnostic usefulness of synovial biopsies in the light of actual developments.

Cystic pseudotumours in both upper ankle joints in gouty arthritis

This case demonstrates a yet unreported clinical entity of bilateral tophaceous cystic lesions of the tibiotalar joints of an 37-year-old white male who presents with moderate painful swelling in both upper ankle joints for 2 years. Radiodiagnostic studies show cystic lesions in both upper ankle joints and the right talus considering neoplastic processes in the differential diagnosis. The incisional biopsy reveals chalk-like material of the intraosseous lesions which was pathognomonic for tophaceous gout. Antihyperuricemic medication led to a stagnation of growth of the lesions without a sign of osseous remodeling. However, due to limitation of discomfort, personal preferences and a lack of surgical options conservative treatment was maintained.