title: Prevalence of monosodium urate deposits in a population of rheumatoid arthritis patients with hyperuricemia.
abstract: To investigate the prevalence of monosodium urate (MSU) crystal deposits, indicative for gout, in a population of rheumatoid arthritis (RA) patients with concomitant hyperuricemia and to analyze the clinical and disease-specific characteristics of RA patients who exhibit MSU crystal deposits.
  
  
  
  Overall, 100 consecutive patients with the diagnosis of RA and a serum urate level above 6mg/dl underwent dual energy computed tomography (DECT) of both feet and hands to search for MSU crystals in a prospective study between October 2011 and July 2013. Presence and extent of MSU crystal deposits on DECT was assessed by automated volume measurement. Demographic and disease-specific characteristics were recorded and included into two logistic regression models to test for the factors associated with MSU crystal deposits in RA.
  
  
  
  Hyperuricemic RA patients were mostly male (55%), over 60 years of age (63 ± 11 years), had established disease (8.7 ± 10.5 years) and a mean disease activity score 28 (DAS 28) of 3.2. In total, 20 out of 100 patients displayed MSU crystal deposits in DECT. Interestingly, the majority (70%) of the RA patients positive for MSU crystal deposits were seronegative RA patients. Hence, every third seronegative RA patient had MSU crystal deposits. According to logistic regression model analysis, seronegative status correlated positively with presence of urate deposits (p = 0.019).
  
  
  
  These data show that a considerable number of RA patients display periarticular MSU crystal deposits. Seronegative patients were shown to be predominantly affected with every third patient being positive for urate deposits.
authors.affiliation: Department of Internal Medicine 3, Rheumatology and Immunology, University of Erlangen-Nuremberg, Ulmenweg 18, 91054 Erlangen, Germany.
authors.forename: Christina
authors.initials: C
authors.lastname: Petsch
authors.affiliation: Department of Internal Medicine 3, Rheumatology and Immunology, University of Erlangen-Nuremberg, Ulmenweg 18, 91054 Erlangen, Germany.
authors.forename: Elizabeth G
authors.initials: EG
authors.lastname: Araujo
authors.affiliation: Department of Internal Medicine 3, Rheumatology and Immunology, University of Erlangen-Nuremberg, Ulmenweg 18, 91054 Erlangen, Germany.
authors.forename: Matthias
authors.initials: M
authors.lastname: Englbrecht
authors.affiliation: Department of Internal Medicine 3, Rheumatology and Immunology, University of Erlangen-Nuremberg, Ulmenweg 18, 91054 Erlangen, Germany.
authors.forename: Sara
authors.initials: S
authors.lastname: Bayat
authors.affiliation: Department of Radiology, University of Erlangen-Nuremberg, Ulmenweg 18, 91054 Erlangen, Germany.
authors.forename: Alexander
authors.initials: A
authors.lastname: Cavallaro
authors.affiliation: Department of Internal Medicine 3, Rheumatology and Immunology, University of Erlangen-Nuremberg, Ulmenweg 18, 91054 Erlangen, Germany.
authors.forename: Axel J
authors.initials: AJ
authors.lastname: Hueber
authors.affiliation: Department of Radiology, University of Erlangen-Nuremberg, Ulmenweg 18, 91054 Erlangen, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Lell
authors.affiliation: Department of Internal Medicine 3, Rheumatology and Immunology, University of Erlangen-Nuremberg, Ulmenweg 18, 91054 Erlangen, Germany.
authors.forename: Georg
authors.initials: G
authors.lastname: Schett
authors.affiliation: Department of Internal Medicine 3, Rheumatology and Immunology, University of Erlangen-Nuremberg, Ulmenweg 18, 91054 Erlangen, Germany.
authors.forename: Bernhard
authors.initials: B
authors.lastname: Manger
authors.affiliation: Department of Internal Medicine 3, Rheumatology and Immunology, University of Erlangen-Nuremberg, Ulmenweg 18, 91054 Erlangen, Germany. Electronic address: juergen.rech@uk-erlangen.de.
authors.forename: Juergen
authors.initials: J
authors.lastname: Rech
mesh_terms: D017677:Age Distribution; D000368:Aged; D001172:Arthritis, Rheumatoid / Q000097:blood / Q000000981:diagnostic imaging / Q000453:epidemiology* / Q000276:immunology; D015897:Comorbidity; D005260:Female; D033023:Foot Joints / Q000000981:diagnostic imaging*; D006073:Gout / Q000097:blood / Q000000981:diagnostic imaging / Q000453:epidemiology*; D050823:Hand Joints / Q000000981:diagnostic imaging*; D006801:Humans; D033461:Hyperuricemia / Q000453:epidemiology*; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D011446:Prospective Studies; D012217:Rheumatoid Factor / Q000276:immunology; D017678:Sex Distribution; D014057:Tomography, X-Ray Computed; D014527:Uric Acid
chemical_list: D014527:Uric Acid; D012217:Rheumatoid Factor
keywords: Dual energy computed tomography; Gout; Hyperuricemia; Monosodium urate; Rheumatoid arthritis