title: Routine ultrasound and limited computed tomography for the diagnosis of acute appendicitis.
abstract: BACKGROUND
  Acute appendicitis continues to be a challenging diagnosis. Preoperative radiological imaging using ultrasound (US) or computed tomography (CT) has gained popularity as it may offer a more accurate diagnosis than classic clinical evaluation. The optimal implementation of these diagnostic modalities has yet to be established. The aim of the present study was to investigate a diagnostic pathway that uses routine US, limited CT, and clinical re-evaluation for patients with acute appendicitis.
  
  
  METHODS
  A prospective analysis was performed of all patients presenting with acute abdominal pain at the emergency department from June 2005 until July 2006 using a structured diagnosis and management flowchart. Daily practice was mimicked, while ensuring a valid assessment of clinical and radiological diagnostic accuracies and the effect they had on patient management.
  
  
  RESULTS
  A total of 802 patients were included in this analysis. Additional radiological imaging was performed in 96.3% of patients with suspected appendicitis (n = 164). Use of CT was kept to a minimum (17.9%), with a US:CT ratio of approximately 6:1. Positive and negative predictive values for the clinical diagnosis of appendicitis were 63 and 98%, respectively; for US 94 and 97%, respectively; and for CT 100 and 100%, respectively. The negative appendicitis rate was 3.3%, the perforation rate was 23.5%, and the missed perforated appendicitis rate was 3.4%. No (diagnostic) laparoscopies were performed.
  
  
  CONCLUSIONS
  A diagnostic pathway using routine US, limited CT, and clinical re-evaluation for patients with acute abdominal pain can provide excellent results for the diagnosis and treatment of appendicitis.
authors.affiliation: Department of Surgery, Leiden University Medical Centre, P.O. Box 9600, 2300 RC, Leiden, The Netherlands. br.toorenvliet@tiscali.nl
authors.forename: Boudewijn R
authors.initials: BR
authors.lastname: Toorenvliet
authors.forename: Fraukje
authors.initials: F
authors.lastname: Wiersma
authors.forename: Rutger F R
authors.initials: RF
authors.lastname: Bakker
authors.forename: Jos W S
authors.initials: JW
authors.lastname: Merkus
authors.forename: Paul J
authors.initials: PJ
authors.lastname: Breslau
authors.forename: Jaap F
authors.initials: JF
authors.lastname: Hamming
mesh_terms: D015746:Abdominal Pain / Q000000981:diagnostic imaging / Q000601:surgery; D000208:Acute Disease; D000293:Adolescent; D000328:Adult; D001062:Appendectomy; D001064:Appendicitis / Q000000981:diagnostic imaging* / Q000601:surgery; D002648:Child; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D014057:Tomography, X-Ray Computed; D014463:Ultrasonography; D055815:Young Adult