title: Comparison between colour duplex sonography findings and different histological patterns of temporal artery.
abstract: OBJECTIVE
  To assess the findings of temporal artery colour duplex sonography (CDS) in GCA characterized by a histological pattern of periadventitial small vessel vasculitis (SVV) and/or vasa vasorum vasculitis (VVV) and compare it with those observed in classic GCA with transmural vasculitis.
  
  
  METHODS
  We studied 30 patients with SVV and/or VVV, 63 patients with classic GCA and 67 biopsy-negative patients identified over a 9-year period. CDS of the temporal arteries was performed in all patients by one ultrasonographer. Temporal artery biopsy was used as the reference standard. Sensitivities, specificities and likelihood ratios (LRs) were calculated.
  
  
  RESULTS
  The frequency of the halo sign on CDS was significantly lower in the patients with SVV and/or VVV compared with those with classic GCA (20% vs 82.5%, P = 0.0001). The halo sign had a sensitivity of only 20% (95% CI 8.4, 39.1%) and a specificity of 80.6% (95% CI 68.7, 88.9%) for the diagnosis of SVV and/or VVV. The negative LR was 0.992 (CI 0.824, 1.195), and the positive LR was 1.030 (CI 0.433, 2.451). The halo sign for the diagnosis of biopsy-proven classic GCA had a higher sensitivity of 82.5% (CI 70.5, 90.5%), the same specificity of 80.6% (CI 68.7, 88.9%) and a higher positive LR (4.253; CI 2.577, 7.021).
  
  
  CONCLUSIONS
  The halo sign is infrequently found in GCA characterized by a histological pattern of SVV and/or VVV. This limits the sensitivity of CDS in correctly identifying patients with GCA.
authors.affiliation: Rheumatology Unit, IRCSS - Arcispedale Santa Maria Nuova, Viale Risorgimento 80, 42100 Reggio Emilia, Italy. salvarani.carlo@asmn.re.it.
authors.forename: Francesco
authors.initials: F
authors.lastname: Muratore
authors.forename: Luigi
authors.initials: L
authors.lastname: Boiardi
authors.forename: Giovanna
authors.initials: G
authors.lastname: Restuccia
authors.forename: Pierluigi
authors.initials: P
authors.lastname: Macchioni
authors.forename: Giulia
authors.initials: G
authors.lastname: Pazzola
authors.forename: Alberto
authors.initials: A
authors.lastname: Nicolini
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Germanò
authors.forename: Niccolò
authors.initials: N
authors.lastname: Possemato
authors.forename: Alberto
authors.initials: A
authors.lastname: Cavazza
authors.forename: Silvio
authors.initials: S
authors.lastname: Cavuto
authors.forename: Luca
authors.initials: L
authors.lastname: Cimino
authors.forename: Nicolò
authors.initials: N
authors.lastname: Pipitone
authors.forename: Mariagrazia
authors.initials: M
authors.lastname: Catanoso
authors.forename: Olga
authors.initials: O
authors.lastname: Addimanda
authors.forename: Carlo
authors.initials: C
authors.lastname: Salvarani
mesh_terms: D000368:Aged; D001706:Biopsy; D005260:Female; D013700:Giant Cell Arteritis / Q000000981:diagnostic imaging* / Q000473:pathology*; D006801:Humans; D008297:Male; D011446:Prospective Studies; D012680:Sensitivity and Specificity; D013699:Temporal Arteries / Q000000981:diagnostic imaging* / Q000473:pathology*; D018615:Ultrasonography, Doppler, Color
keywords: giant cell arteritis; halo; periadventitial small-vessel vasculitis; transmural vasculitis; ultrasonography