title: Exploratory study of radiographic change in patients with tophaceous gout treated with intensive urate-lowering therapy.
abstract: OBJECTIVE
  Tophi are strongly associated with structural damage in gout, and urate-lowering therapy reduces tophus size. Pegloticase leads to dramatic reductions in serum urate and subcutaneous tophi in treatment responders. The aim of this analysis was to examine whether profound urate lowering can alter radiographic findings in gout.
  
  
  METHODS
  Serial plain radiographs of the hands and feet were obtained from 8 patients with tophaceous gout treated with pegloticase. Radiographs were scored for erosion and joint space narrowing (JSN) according to the gout-modified Sharp/van der Heijde method. Scorers were blinded to each other's scores and to the clinical characteristics of the patients (including the clinical response to pegloticase). A detailed qualitative site-by-site analysis was undertaken to define additional changes observed from baseline.
  
  
  RESULTS
  All patients experienced a profound urate-lowering response (serum urate level <1 mg/dl) during pegloticase treatment. For the entire group, the median total radiographic scores reduced from 69.25 (range 1.5-138) at baseline to 57.25 (range 1.5-110) at 12 months (P = 0.02). Median erosion scores reduced over 1 year (P = 0.008), but JSN scores did not change (P = 0.50). Further reductions were observed in total scores and erosion scores in 5 patients with 24-month followup films (one-way analysis of variance P = 0.009 for total score, 0.02 for erosion, and 0.95 for JSN). Qualitative site-by-site analysis identified regression of soft tissue masses, increased sclerosis, and filling in of erosions in the followup films.
  
  
  CONCLUSIONS
  This exploratory study suggests that profound urate lowering can lead to improvement in structural damage, particularly bone erosion, in patients with tophaceous gout.
authors.affiliation: University of Auckland, Auckland, New Zealand.
authors.forename: Nicola
authors.initials: N
authors.lastname: Dalbeth
authors.forename: Anthony J
authors.initials: AJ
authors.lastname: Doyle
authors.forename: Fiona M
authors.initials: FM
authors.lastname: McQueen
authors.forename: John
authors.initials: J
authors.lastname: Sundy
authors.forename: Herbert S B
authors.initials: HS
authors.lastname: Baraf
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D003460:Crystallization; D018450:Disease Progression; D005260:Female; D033023:Foot Joints / Q000000981:diagnostic imaging* / Q000473:pathology; D006073:Gout / Q000097:blood / Q000000981:diagnostic imaging* / Q000188:drug therapy*; D006074:Gout Suppressants / Q000627:therapeutic use*; D050823:Hand Joints / Q000000981:diagnostic imaging* / Q000473:pathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D011092:Polyethylene Glycols / Q000627:therapeutic use*; D011859:Radiography; D016896:Treatment Outcome; D014503:Urate Oxidase / Q000627:therapeutic use*; D014527:Uric Acid / Q000097:blood
chemical_list: D006074:Gout Suppressants; D014527:Uric Acid; D011092:Polyethylene Glycols; D014503:Urate Oxidase; C031545:Pegloticase