title: Performance of ultrasound in the diagnosis of appendicitis in children in a multicenter cohort.
abstract: OBJECTIVE
  The objectives were to assess the test characteristics of ultrasound (US) in diagnosing appendicitis in children and to evaluate site-related variations based on the frequency of its use. Additionally, the authors assessed the test characteristics of US when the appendix was clearly visualized.
  
  
  METHODS
  This was a secondary analysis of a prospective, 10-center observational study. Children aged 3 to 18 years with acute abdominal pain concerning for appendicitis were enrolled. US was performed at the discretion of the treating physician.
  
  
  RESULTS
  Of 2,625 patients enrolled, 965 (36.8%) underwent abdominal US. US had an overall sensitivity of 72.5% (95% confidence interval [CI] = 58.8% to 86.3%) and specificity 97.0% (95% CI = 96.2% to 97.9%) in diagnosing appendicitis. US sensitivity was 77.7% at the three sites (combined) that used it in 90% of cases, 51.6% at a site that used it in 50% of cases, and 35% at the four remaining sites (combined) that used it in 9% of cases. US retained a high specificity of 96% to 99% at all sites. Of the 469 (48.6%) cases across sites where the appendix was clearly visualized on US, its sensitivity was 97.9% (95% CI = 95.2% to 99.9%), with a specificity of 91.7% (95% CI = 86.7% to 96.7%).
  
  
  CONCLUSIONS
  Ultrasound sensitivity and the rate of visualization of the appendix on US varied across sites and appeared to improve with more frequent use. US had universally high sensitivity and specificity when the appendix was clearly identified. Other diagnostic modalities should be considered when the appendix is not definitively visualized by US.
authors.affiliation: Department of Pediatrics, The Children's Hospital of Philadelphia, Perelman School of Medicine, University of Pennsylvania , Philadelphia, PA, USA. Mittal@email.chop.edu
authors.forename: Manoj K
authors.initials: MK
authors.lastname: Mittal
authors.forename: Peter S
authors.initials: PS
authors.lastname: Dayan
authors.forename: Charles G
authors.initials: CG
authors.lastname: Macias
authors.forename: Richard G
authors.initials: RG
authors.lastname: Bachur
authors.forename: Jonathan
authors.initials: J
authors.lastname: Bennett
authors.forename: Nanette C
authors.initials: NC
authors.lastname: Dudley
authors.forename: Lalit
authors.initials: L
authors.lastname: Bajaj
authors.forename: Kelly
authors.initials: K
authors.lastname: Sinclair
authors.forename: Michelle D
authors.initials: MD
authors.lastname: Stevenson
authors.forename: Anupam B
authors.initials: AB
authors.lastname: Kharbanda
mesh_terms: D015746:Abdominal Pain / Q000175:diagnosis / Q000209:etiology; D000293:Adolescent; D001062:Appendectomy / Q000379:methods; D001064:Appendicitis / Q000175:diagnosis / Q000000981:diagnostic imaging* / Q000601:surgery; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D016001:Confidence Intervals; D004636:Emergency Service, Hospital; D005260:Female; D006776:Hospitals, Pediatric; D006801:Humans; D008297:Male; D011446:Prospective Studies; D018570:Risk Assessment; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D016896:Treatment Outcome; D018608:Ultrasonography, Doppler / Q000379:methods*