title: Ultrasound for Diagnosis of Appendicitis in a Community Hospital Emergency Department has a High Rate of Nondiagnostic Studies.
abstract: BACKGROUND
  Radiation concerns are changing the way emergency physicians evaluate patients. This is especially prevalent in pediatrics, and exemplified by abdominal pain management. Large academic center-based studies suggest appendix ultrasound (U/S) is sensitive and specific for appendicitis, with low nondiagnostic rates.
  
  
  OBJECTIVE
  We sought to determine the diagnostic rate of appendix U/S and incidence of follow-up computed tomography (CT) imaging for pediatric patients at a community hospital.
  
  
  METHODS
  Design: Retrospective cohort.
  
  
  METHODS
  Emergency department with 85,000 annual visits.
  
  
  METHODS
  Patients younger than 21 years old that had an appendix U/S over a 12-month period. U/S were performed by technicians and interpreted by radiologists. Investigators classified readings as "diagnostic" ("positive" and "negative") or "non-diagnostic" ("borderline" and "appendix not visualized") and identified follow-up CT studies and interpretations.
  
  
  RESULTS
  There were 441 pediatric appendix U/S performed; 26% were diagnostic (14% positive for appendicitis, 12% negative) and 74% nondiagnostic (5% borderline, 69% appendix not visualized). Follow-up CT scans were obtained in 19% of all patients, including 8% with positive U/S, 4% negative, 32% borderline, and 22% not visualized. Follow-up CT was nearly four times more likely in the nondiagnostic group than the diagnostic group (23% vs. 6%, p < 0.0001).
  
  
  CONCLUSIONS
  The utility of U/S to diagnose appendicitis at a community hospital is limited by a high rate of nondiagnostic studies. Some patients with diagnostic U/S even had follow-up CT imaging. To minimize radiation exposure in children, improvements should be made in the performance and acceptance of U/S as the primary modality of abdominal pain imaging at community hospitals.
authors.affiliation: Division of Emergency Medicine, Charles E. Schmidt College of Medicine, Florida Atlantic University, Boca Raton, Florida.
authors.forename: Scott M
authors.initials: SM
authors.lastname: Alter
authors.affiliation: Department of Emergency Medicine, Morristown Medical Center, Morristown, New Jersey.
authors.forename: Brian
authors.initials: B
authors.lastname: Walsh
authors.affiliation: Department of Emergency Medicine, California Hospital Medical Center, Los Angeles, California.
authors.forename: Patrick J
authors.initials: PJ
authors.lastname: Lenehan
authors.affiliation: Division of Emergency Medicine, Charles E. Schmidt College of Medicine, Florida Atlantic University, Boca Raton, Florida.
authors.forename: Richard D
authors.initials: RD
authors.lastname: Shih
mesh_terms: D015746:Abdominal Pain / Q000209:etiology; D000293:Adolescent; D001064:Appendicitis / Q000175:diagnosis* / Q000453:epidemiology; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D004636:Emergency Service, Hospital / Q000458:organization & administration / Q000706:statistics & numerical data; D005260:Female; D006764:Hospitals, Community / Q000458:organization & administration / Q000706:statistics & numerical data; D006801:Humans; D007223:Infant; D008297:Male; D011873:Radiology Information Systems / Q000706:statistics & numerical data; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed / Q000379:methods; D014463:Ultrasonography / Q000379:methods / Q000706:statistics & numerical data*; D014481:United States / Q000453:epidemiology; D055815:Young Adult
keywords: appendix; community; emergency; pediatrics; ultrasound