Time Required for Disappearance of Urate Crystals from Synovial Fluid After Successful Hypouricaemic Treatment Relates to the Duration of Gout
Overview
Authors
Affiliations
Objectives: To determine whether hypouricaemic treatment results in the disappearance of urate crystals from gouty joints and to define the time required.
Methods: In 18 patients with monosodium urate (MSU) crystal proven gout, and after the initiation of successful serum uric acid (SUA)-lowering treatment, an arthrocentesis of the asymptomatic signal joint (11 knees, 7 first metatarsophalangeal joints) was performed every 3 months to obtain a synovial fluid (SF) sample. The sample was then analysed for the presence of MSU crystals, and the number of crystals/400x field was noted. SUA levels and the duration of gout were also noted.
Results: MSU crystals disappeared from the SF of all 18 joints after reduction of SUA to normal levels. The time required for disappearance ranged from 3 to 33 months; disappearance time correlated with the duration of gout (r(s) = 0.71; p<0.01). The median number of MSU crystals in the SF samples before urate-lowering treatment was 7.5 (2.5-11) crystals/400x field, reducing to 3 (1-6.5) crystals/400x field (p<0.05) at 3 months. Crystal counts continued to decrease after 3 months.
Conclusions: In gout, reduction of SUA to normal levels results in disappearance of urate crystals from SF, requiring a longer time in those patients with gout of longer duration. This indicates that urate crystal deposition in joints is reversible. Normalisation of SUA levels results in a decrease in the concentration of MSU crystals in SF in the asymptomatic gouty joints. This may partially explain the reduced frequency of gouty attacks when a patient has been treated with SUA-lowering drugs.
Peeters I, den Broeder A, Taylor W, den Broeder N, Flendrie M, van Herwaarden N Trials. 2023; 24(1):282.
PMID: 37072799 PMC: 10114395. DOI: 10.1186/s13063-023-07242-y.
The Hong Kong Society of Rheumatology consensus recommendations for the management of gout.
Yip R, Cheung T, So H, Chan J, Ho C, Tsang H Clin Rheumatol. 2023; 42(8):2013-2027.
PMID: 37014501 PMC: 10345000. DOI: 10.1007/s10067-023-06578-9.
Critical appraisal of serum urate targets in the management of gout.
Stamp L, Dalbeth N Nat Rev Rheumatol. 2022; 18(10):603-609.
PMID: 35974164 DOI: 10.1038/s41584-022-00816-1.
Hooper M, He L J Pain Res. 2022; 15:1825-1835.
PMID: 35791391 PMC: 9250783. DOI: 10.2147/JPR.S367536.
Dietary supplements for chronic gout.
Andres M, Sivera F, Buchbinder R, Pardo J, Carmona L Cochrane Database Syst Rev. 2021; 11:CD010156.
PMID: 34767649 PMC: 8589461. DOI: 10.1002/14651858.CD010156.pub3.