title: Unexpected findings after surgery for suspected appendicitis rarely change treatment in pediatric patients; Results from a cohort study.
abstract: BACKGROUND
  To determine if non-operative treatment is safe in children with acute appendicitis, we evaluated the incidence of unexpected findings after an appendectomy in children, and the influence they have on subsequent treatment.
  
  
  METHODS
  A historical cohort study (January 2004-December 2014) was performed including children, aged 0-17 years, who underwent an appendectomy for the suspicion of acute appendicitis. Patients were divided based upon histopathological examination. Unexpected findings were reviewed, as well as the subsequent treatment plan.
  
  
  RESULTS
  In total 484 patients were included in this study. In the overall group, unexpected findings were noted in 10 (2.1%) patients of which two patients intra-operatively with a non-inflamed appendix (Ileitis terminalis N=1 and ovarian torsion N=1) and in 8 patients on histopathological examination. The latter group consisted of 4 patients with concomitant simple appendicitis (parasitic infection N=3 and Walthard cell rest N=1), two with concomitant complex appendicitis (carcinoid N=1 and parasitic infection N=1) and two patients with a non-inflamed appendix (endometriosis N=1 and parasitic infection N=1). Treatment was changed in 4 patients (<1%).
  
  
  CONCLUSIONS
  Results from this study corroborate the safety of non-operative strategy for acute simple appendicitis, as the occurrence of unexpected findings was low, with extremely few necessary changes of the treatment plan because of serious findings.
  
  
  METHODS
  Prognosis study.
  
  
  METHODS
  Level 2 (retrospective cohort study).
authors.affiliation: Paediatric Surgical Centre of Amsterdam, Emma Children's Hospital AMC & VU University Medical Centre, P.O. Box 22660, 1100DD Amsterdam, The Netherlands; Department of Surgery, Red Cross Hospital, Vondellaan 13 1942 LE, Beverwijk, The Netherlands. Electronic address: rr.gorter@vumc.nl.
authors.forename: Ramon R
authors.initials: RR
authors.lastname: Gorter
authors.affiliation: Paediatric Surgical Centre of Amsterdam, Emma Children's Hospital AMC & VU University Medical Centre, P.O. Box 22660, 1100DD Amsterdam, The Netherlands. Electronic address: p.van.amstel@student.vu.nl.
authors.forename: Paul
authors.initials: P
authors.lastname: van Amstel
authors.affiliation: Paediatric Clinical Research Office, Division Woman and Child, Academic Medical Centre, Meibergdreef 9, 1105AZ Amsterdam, The Netherlands. Electronic address: j.h.vanderlee@amc.uva.nl.
authors.forename: Johanna H
authors.initials: JH
authors.lastname: van der Lee
authors.affiliation: Department of Pathology, VU University Medical Centre, De Boelelaan 1117, 1081HV Amsterdam, The Netherlands. Electronic address: jp.vanderVoorn@vumc.nl.
authors.forename: Patick
authors.initials: P
authors.lastname: van der Voorn
authors.affiliation: Paediatric Surgical Centre of Amsterdam, Emma Children's Hospital AMC & VU University Medical Centre, P.O. Box 22660, 1100DD Amsterdam, The Netherlands. Electronic address: r.bakx@amc.uva.nl.
authors.forename: Roel
authors.initials: R
authors.lastname: Bakx
authors.affiliation: Paediatric Surgical Centre of Amsterdam, Emma Children's Hospital AMC & VU University Medical Centre, P.O. Box 22660, 1100DD Amsterdam, The Netherlands. Electronic address: hugo.heij@icloud.com.
authors.forename: Hugo A
authors.initials: HA
authors.lastname: Heij
mesh_terms: D000208:Acute Disease; D000293:Adolescent; D001062:Appendectomy; D001063:Appendiceal Neoplasms / Q000175:diagnosis; D001064:Appendicitis / Q000473:pathology / Q000601:surgery*; D001065:Appendix / Q000473:pathology* / Q000601:surgery; D002276:Carcinoid Tumor / Q000175:diagnosis; D002648:Child; D002675:Child, Preschool; D004715:Endometriosis / Q000175:diagnosis; D017229:Enterobiasis / Q000175:diagnosis; D005260:Female; D006801:Humans; D015994:Incidence; D033162:Incidental Findings; D007223:Infant; D008297:Male; D010049:Ovarian Diseases / Q000175:diagnosis; D012189:Retrospective Studies; D014102:Torsion Abnormality / Q000175:diagnosis
keywords: Appendectomy; Appendicitis; Unexpected findings