title: Dual-energy computed tomography for monitoring the effect of urate-lowering therapy in gouty arthritis.
abstract: OBJECTIVE
  To investigate the relationships between changes in serum urate levels and dual-energy computed tomography (DE-CT) results during urate-lowering therapy (ULT) and to investigate the effects of treatment duration and drugs on changes in DE-CT results.
  
  
  METHODS
  Forty-four patients diagnosed with gout were enrolled in this investigation. DE-CT was conducted on the foot at baseline and the end of follow-up (6-24 months). Crystals were classified as: (i) L, number of large crystals with diameter ≥ 3 mm; (ii) S, number of small crystals with diameter < 3 mm; (iii) T, total number of crystals; and (iv) Vmax, volume of the maximal crystal.
  
  
  RESULTS
  Number of urate crystals (L, S as well as T) and Vmax decreased significantly through ULT. Significant decrease of urate crystal numbers and/or Vmax was observed in different follow-up groups, and the decrease in serum urate levels was positively related to the decrease of T (r = 0.43, P = 0.04) and Vmax (r = 0.63, P = 0.04). Moreover, analysis of covariance results demonstrated significant effects of treatment duration and serum urate levels on results of DE-CT.
  
  
  CONCLUSIONS
  Both urate crystal numbers and Vmax decreased significantly during ULT. Additionally, ULT duration and serum urate levels had significant effects on the decrease of Vmax and number of large crystals measured by DE-CT.
authors.affiliation: Department of Rheumatology, Zhongshan Hospital, Fudan University, Shanghai, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Sun
authors.affiliation: Department of Rheumatology, Zhongshan Hospital, Fudan University, Shanghai, China.
authors.forename: Huiyong
authors.initials: H
authors.lastname: Chen
authors.affiliation: Department of Rheumatology, Zhongshan Hospital, Fudan University, Shanghai, China.
authors.forename: Zhuojun
authors.initials: Z
authors.lastname: Zhang
authors.affiliation: Department of Rheumatology, Zhongshan Hospital, Fudan University, Shanghai, China.
authors.forename: Lili
authors.initials: L
authors.lastname: Ma
authors.affiliation: Department of Radiology, Zhongshan Hospital, Fudan University, Shanghai, China.
authors.forename: Jianjun
authors.initials: J
authors.lastname: Zhou
authors.affiliation: Department of Radiology, Zhongshan Hospital, Fudan University, Shanghai, China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Zhou
authors.affiliation: Department of Radiology, Zhongshan Hospital, Fudan University, Shanghai, China.
authors.forename: Yuqin
authors.initials: Y
authors.lastname: Ding
authors.affiliation: Department of Statistics, Zhongshan Hospital, Fudan University, Shanghai, China.
authors.forename: Xuejuan
authors.initials: X
authors.lastname: Jin
authors.affiliation: Department of Rheumatology, Zhongshan Hospital, Fudan University, Shanghai, China.
authors.forename: Lindi
authors.initials: L
authors.lastname: Jiang
mesh_terms: D000328:Adult; D000368:Aged; D015210:Arthritis, Gouty / Q000097:blood / Q000000981:diagnostic imaging* / Q000188:drug therapy*; D015415:Biomarkers / Q000097:blood; D003460:Crystallization; D016903:Drug Monitoring / Q000379:methods*; D005260:Female; D005529:Foot Bones / Q000000981:diagnostic imaging* / Q000187:drug effects* / Q000378:metabolism; D006074:Gout Suppressants / Q000627:therapeutic use*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome; D014527:Uric Acid / Q000097:blood*
chemical_list: D015415:Biomarkers; D006074:Gout Suppressants; D014527:Uric Acid
keywords: dual-energy computed tomography; gouty arthritis; urate-lowering therapy; uric acid