title: Sensitivity and specificity of ultrasonographic features of gout in intercritical and chronic phase.
abstract: OBJECTIVE
  This study aimed to assess the sensitivity and specificity of ultrasonographic features of gout in intercritical and chronic stages and compared ultrasonographic features of gout between patients with persistent high serum uric acid (SUA) and patients with low SUA.
  
  
  METHODS
  Adult patients with gout confirmed by demonstration of monosodium urate crystals were recruited, if they were in intercritical or chronic stage clinically. Ultrasonographic examination of the first metatarsophalangeal joints (MTPJs) and the knee joints of both sides were done by a blinded rheumatologist trained in musculoskeletal ultrasound.
  
  
  RESULTS
  Sixty-two patients with gout and 30 control subjects were examined. The double contour sign (DCS) was found in 71 (57.3%) first MTPJs and tophi were found in 54 (43.5%) first MTPJs. DCS was present in 43 (69.4%) gout patients but none in the control group (P < 0.001). Sensitivity and specificity (95% CI) of DCS in gout patients were 69.4% (56.4-80.4%) and 100% (88.3-100%), respectively, while of tophi they were 66.1% (53-77.7%) and 100% (88.3-100%), respectively. The sensitivity of DCS increased to 100% in high the SUA subgroup (SUA ≥ 7 mg/dL). The low SUA (SUA < 7 mg/dL) gout subgroup showed significantly higher occurrence of erosions (40%) and tophi (50%) in first MTP joints than the control group.
  
  
  CONCLUSIONS
  MSUS is useful for diagnosis of gout in intercritical or chronic stages, especially in patients with persistently high SUA level.
authors.affiliation: Department of Rheumatology, Institute of Postgraduate Medical Education and Research, Kolkata, West Bengal, India.
authors.forename: Shyamashis
authors.initials: S
authors.lastname: Das
authors.affiliation: Department of Rheumatology, Institute of Postgraduate Medical Education and Research, Kolkata, West Bengal, India.
authors.forename: Alakendu
authors.initials: A
authors.lastname: Ghosh
authors.affiliation: Department of Rheumatology, Institute of Postgraduate Medical Education and Research, Kolkata, West Bengal, India.
authors.forename: Parasar
authors.initials: P
authors.lastname: Ghosh
authors.affiliation: Department of Rheumatology, Institute of Postgraduate Medical Education and Research, Kolkata, West Bengal, India.
authors.forename: Debasish
authors.initials: D
authors.lastname: Lahiri
authors.affiliation: Department of Rheumatology, Institute of Postgraduate Medical Education and Research, Kolkata, West Bengal, India.
authors.forename: Pradyot
authors.initials: P
authors.lastname: Sinhamahapatra
authors.affiliation: Department of Rheumatology, Institute of Postgraduate Medical Education and Research, Kolkata, West Bengal, India.
authors.forename: Kaushik
authors.initials: K
authors.lastname: Basu
mesh_terms: D000328:Adult; D015415:Biomarkers / Q000097:blood; D016022:Case-Control Studies; D002908:Chronic Disease; D003430:Cross-Sectional Studies; D005260:Female; D006073:Gout / Q000097:blood / Q000000981:diagnostic imaging*; D006801:Humans; D007719:Knee Joint / Q000737:chemistry / Q000000981:diagnostic imaging*; D008297:Male; D008683:Metatarsophalangeal Joint / Q000737:chemistry / Q000000981:diagnostic imaging*; D008875:Middle Aged; D015588:Observer Variation; D011237:Predictive Value of Tests; D011446:Prospective Studies; D015203:Reproducibility of Results; D012720:Severity of Illness Index; D014463:Ultrasonography; D014527:Uric Acid / Q000097:blood
chemical_list: D015415:Biomarkers; D014527:Uric Acid
keywords: double contour sign; gout; gout imaging; ultrasonography in gout; uric acid