title: The effect of the systemic inflammatory response, as provoked by elective orthopaedic surgery, on serum uric acid in patients without gout: a prospective study.
abstract: OBJECTIVE
  Acute gout is associated with a decrease in serum uric acid (SUA) that is considered to be in response to acute inflammation but it may be a feature of gout itself. We, therefore, aimed to investigate the effect of the acute systemic inflammatory response (SIR) on SUA concentrations in subjects without gout.
  
  
  METHODS
  SUA and urinary excretion of uric acid (UA) (expressed as fractional excretion of UA; FEua%) were measured in 30 patients before and 48 h after elective knee or hip surgery. The SIR was assessed by measuring serum CRP and urine microalbumin excretion [expressed as the albumin-creatinine ratio (ACR)] before and after surgery in the same patients.
  
  
  RESULTS
  The mean (s.d.) serum CRP increased following surgery [5.0 (5.5) vs 116.0 (81.2) mg/l; P < 0.0001) as did urine ACR [0.85 (1.03) vs 2.10 (2.60) mg/mmol; P = 0.004]. SUA decreased following surgery [312 (64) vs 282 (82) µmol/l; P = 0.0033] but FEua% was unchanged [6.4 (2.3) vs 7.3 (3.3)%; P = 0.1726].
  
  
  CONCLUSIONS
  The SIR is associated with a decrease in SUA concentrations in normouricaemic patients without gout. The decrease in SUA concentrations is not due to increased urinary excretion of UA. This study supports the notion that the decrease in SUA during acute gout is due to the associated SIR rather than gout per se.
authors.affiliation: Department of Clinical Chemistry, New Cross Hospital, Wolverhampton, West Midlands, UK. jenna.waldron@nhs.net
authors.forename: Jenna L
authors.initials: JL
authors.lastname: Waldron
authors.forename: Helen L
authors.initials: HL
authors.lastname: Ashby
authors.forename: Cyrus
authors.initials: C
authors.lastname: Razavi
authors.forename: Osmond L
authors.initials: OL
authors.lastname: Thomas
authors.forename: Sanjiv
authors.initials: S
authors.lastname: Chugh
authors.forename: Shreeram
authors.initials: S
authors.lastname: Deshpande
authors.forename: Clare
authors.initials: C
authors.lastname: Ford
authors.forename: Rousseau
authors.initials: R
authors.lastname: Gama
mesh_terms: D000368:Aged; D000419:Albuminuria; D002097:C-Reactive Protein / Q000378:metabolism; D003404:Creatinine / Q000652:urine; D017558:Elective Surgical Procedures; D005260:Female; D006073:Gout / Q000097:blood; D006801:Humans; D007249:Inflammation / Q000097:blood / Q000209:etiology* / Q000652:urine; D008297:Male; D008875:Middle Aged; D019637:Orthopedic Procedures / Q000009:adverse effects*; D015207:Osteoarthritis, Hip / Q000097:blood / Q000601:surgery*; D020370:Osteoarthritis, Knee / Q000097:blood / Q000601:surgery*; D011446:Prospective Studies; D014527:Uric Acid / Q000097:blood*
chemical_list: D014527:Uric Acid; D002097:C-Reactive Protein; D003404:Creatinine