title: Association between tonsillectomy, adenoidectomy, and appendicitis.
abstract: BACKGROUND
  Tonsillectomy, with or without adenoidectomy, is one of the most frequent surgical procedures generally performed, especially in young patients. Several studies suggest that there is a relationship between tonsillectomy and altered MALT immune system.
  
  
  OBJECTIVE
  To examine the possible association between tonsillectomy or adenoidectomy and the risk of subsequent appendicitis.
  
  
  METHODS
  A cross-sectional study was performed in 650 patients admitted to the emergency department of a general hospital in Valencia, Spain. Previous history of tonsillectomy and/or adenoidectomy was related to a history of appendectomy. A descriptive study and an analysis of the relationship between previous operations and appendicitis was performed. A multivariable analysis controlled for age and sex was also performed, including the possible interaction of the gender variable. The independent effect of each of the procedures (tonsillectomy, adenoidectomy) was tested.
  
  
  RESULTS
  The 25.5% of patients had undergone tonsillectomy and 11.5% adenoidectomy; 17.5% had had an appendectomy. On average, women were operated on more frequently than men. In the bivariate analysis, both tonsillectomy and adenoidectomy were significantly associated with subsequent appendectomy. In the multivariate analysis, this association was only maintained for tonsillectomy (OR: 3.23; 95% CI: 2.11-4.94). A stratified analysis controlling for sex showed a modification of this effect, with a higher association in women (OR: 5.20; 95% CI: 2.91-9.28) than in men (OR: 1.74; 95% CI: 0.90-3.39).
  
  
  CONCLUSIONS
  A clear association has been found, especially in women, between previous tonsillectomy and subsequent acute appendicitis. Due to a lack of data on acute appendicitis there should be further studies to explain the findings of this study, as this could be the first described risk factor of acute appendicitis.
authors.affiliation: Department of Emergency Medicine, Hospital Arnau de Vilanova, Valencia, Spain. jcandreu@ono.com
authors.forename: J C
authors.initials: JC
authors.lastname: Andreu Ballester
authors.forename: F
authors.initials: F
authors.lastname: Ballester
authors.forename: E
authors.initials: E
authors.lastname: Colomer Rubio
authors.forename: M
authors.initials: M
authors.lastname: Millán Scheiding
mesh_terms: D000233:Adenoidectomy / Q000706:statistics & numerical data*; D000293:Adolescent; D000328:Adult; D001064:Appendicitis / Q000453:epidemiology*; D002648:Child; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012307:Risk Factors; D013997:Time Factors; D014068:Tonsillectomy / Q000706:statistics & numerical data*