title: The rising incidence of pediatric empyema with fistula.
abstract: OBJECTIVE
  The incidence and etiology of empyema with fistula (EWF) in children is unknown. We analyzed a national database to define the epidemiology and diagnoses associated with this condition.
  
  
  METHODS
  Discharge data from the Kids' Inpatient Database were reviewed for EWF (ICD-9 diagnosis code 510.0) in children ≤18 years from 2000 to 2012. Patient characteristics, institutional data, and accompanying conditions were evaluated. Weighted national estimates were calculated and incidence compared across years (2000, 2003, 2006, 2009) using the Rao-Scott Chi Square.
  
  
  RESULTS
  From 2000 to 2012, 908 children were hospitalized with EWF. Age distribution was bimodal. Common primary diagnoses related to the hospitalization were pneumonia/pulmonary abscess (31.2 %) and EWF (19.3 %). Manipulation of the pleural space (e.g. decortication, drainage) comprised 45.0 % of procedures. Incidence rates of EWF increased (Rao Scott Adjusted Chi Square: 16.13, p < 0.01) over the study period. Although not statistically significant, median length of stay and age of diagnosis decreased and increased, respectively.
  
  
  CONCLUSIONS
  This first, national pediatric EWF study reveals rising incidence during the years 2000-2009. Despite limitations in ICD-9 coding, concomitant primary diagnoses and procedures suggest bronchopleural fistulae likely represent the vast majority of cases in this cohort. Multi-institutional studies are needed to confirm etiology and characterize outcome of EWF.
authors.affiliation: Division of Subspecialty General Surgery, Mayo Clinic Department of Surgery, 200 First Street SW, Rochester, MN, 55905, USA. pandian.twinkle@mayo.edu.
authors.forename: T K
authors.initials: TK
authors.lastname: Pandian
authors.affiliation: Division of Subspecialty General Surgery, Mayo Clinic Department of Surgery, 200 First Street SW, Rochester, MN, 55905, USA. aho.johnathon@mayo.edu.
authors.forename: Johnathon M
authors.initials: JM
authors.lastname: Aho
authors.affiliation: Mayo Clinic, Robert D. and Patricia E. Kern Center for the Science of Health Care Delivery, 200 First Street SW, Rochester, MN, 55905, USA. ubl.dan@mayo.edu.
authors.forename: Daniel S
authors.initials: DS
authors.lastname: Ubl
authors.affiliation: Division of Pediatric Surgery, Mayo Clinic Department of Surgery, 200 First Street SW, Rochester, MN, 55905, USA. moir.christopher@mayo.edu.
authors.forename: Christopher R
authors.initials: CR
authors.lastname: Moir
authors.affiliation: Division of Pediatric Surgery, Mayo Clinic Department of Surgery, 200 First Street SW, Rochester, MN, 55905, USA. ishitani.michael@mayo.edu.
authors.forename: Michael B
authors.initials: MB
authors.lastname: Ishitani
authors.affiliation: Mayo Clinic, Robert D. and Patricia E. Kern Center for the Science of Health Care Delivery, 200 First Street SW, Rochester, MN, 55905, USA. habermann.elizabeth@mayo.edu.
authors.forename: Elizabeth B
authors.initials: EB
authors.lastname: Habermann
mesh_terms: D000293:Adolescent; D001983:Bronchial Fistula / Q000453:epidemiology*; D002648:Child; D002675:Child, Preschool; D015897:Comorbidity; D016724:Empyema, Pleural / Q000453:epidemiology*; D005260:Female; D006760:Hospitalization / Q000706:statistics & numerical data; D006801:Humans; D015994:Incidence; D007902:Length of Stay / Q000706:statistics & numerical data; D008297:Male; D012189:Retrospective Studies
keywords: Bronchopleural fistula; Empyema; Empyema with fistula; Pediatrics; Pneumonia