title: Seasonal recurrence of food bolus obstruction in eosinophilic esophagitis.
abstract: BACKGROUND
  Eosinophilic esophagitis (EoE) is a newly recognised condition that is apparently increasing in prevalence, and the aetiology is poorly understood. The role of aeroallergens in EoE is controversial, given the success of dietary therapy. Massive aeroallergen exposure leading to food bolus obstruction events (FBOE) has been described, and the diagnosis of EoE by esophageal biopsy noted to be more common in the pollen season according to previous case series.
  
  
  OBJECTIVE
  To determine if a seasonal variation and a geographical variation occurred in EoE presenting as FBOE in adults, and to track the prevalence of FBOE and EoE over time.
  
  
  METHODS
  A retrospective case-control study analysis was performed from January 2002 to January 2012 to identify all FBOE in adults presenting to five tertiary hospitals in Melbourne, Australia. Endoscopy, histopathological reports, case notes and blood tests were examined, and postcodes recorded. Records of pollen counts were obtained. Cases were defined according to esophageal biopsy and grouped based on month of diagnosis. All other causes of FBOE served as controls.
  
  
  RESULTS
  One thousand, one hundred and thirty-two FBOE were identified. Biopsies were only performed in 278 of these cases, and 85 patients were found to have EoE after biopsy. Patients with EoE were younger (mean age 38 years, range 18-72) compared with those with alternative diagnosis (mean age 64.4 range 22-92), more likely to be male (M : F = 4:1 compared with 1.68:1 ) and had a higher eosinophil count in venous blood. Overall no seasonality was demonstrated in FBOE secondary to any diagnosis, although the six cases of recurrent FBOE secondary to EoE mainly occurred in the grass pollen season in subsequent years. FBOE cases were evenly distributed throughout metropolitan Melbourne irrespective of population density. EoE as a percentage of FBOE increased over time.
  
  
  CONCLUSIONS
  Seasonal aeroallergens may be important for a subgroup of patients with EoE presenting as recurrent FBOE. Esophageal biopsies are performed in a minority of patients, representing a significant departure from ideal management and contributing to recurrent unnecessary FBOE. EoE is an increasingly important cause of FBOE.
authors: Department of Medicine, Monash University, Melbourne, Victoria, Australia.|Department of Gastroenterology, Eastern Health, Melbourne, Victoria, Australia.|Department of Gastroenterology, St Vincents Hospital, Melbourne, Victoria, Australia.
authors: H L
authors: HL
authors: Philpott
authors: Department of Medicine, Monash University, Melbourne, Victoria, Australia.|Department of Gastroenterology, Eastern Health, Melbourne, Victoria, Australia.
authors: S
authors: S
authors: Nandurkar
authors: Department of Medicine, Monash University, Melbourne, Victoria, Australia.|Department of Gastroenterology, Eastern Health, Melbourne, Victoria, Australia.
authors: F
authors: F
authors: Thien
authors: Department of Gastroenterology, St Vincents Hospital, Melbourne, Victoria, Australia.
authors: S
authors: S
authors: Bloom
authors: Department of Gastroenterology, Eastern Health, Melbourne, Victoria, Australia.
authors: E
authors: E
authors: Lin
authors: Department of Gastroenterology, St Vincents Hospital, Melbourne, Victoria, Australia.
authors: R
authors: R
authors: Goldberg
authors: Department of Gastroenterology, The Austin Hospital, Melbourne, Victoria, Australia.
authors: R
authors: R
authors: Boyapati
authors: Department of Medicine, Monash University, Melbourne, Victoria, Australia.
authors: A
authors: A
authors: Finch
authors: Department of Medicine, Monash University, Melbourne, Victoria, Australia.
authors: S G
authors: SG
authors: Royce
authors: Department of Medicine, Monash University, Melbourne, Victoria, Australia.|Department of Gastroenterology, The Alfred Hospital, Melbourne, Victoria, Australia.
authors: P R
authors: PR
authors: Gibson
mesh_terms: D000328:Adult; D000368:Aged; D001315:Australia / Q000453:epidemiology; D016022:Case-Control Studies; D003680:Deglutition Disorders / Q000453:epidemiology* / Q000209:etiology; D057765:Eosinophilic Esophagitis / Q000150:complications / Q000453:epidemiology*; D005260:Female; D005502:Food; D005547:Foreign Bodies / Q000150:complications*; D006801:Humans; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D012008:Recurrence; D012189:Retrospective Studies; D012621:Seasons
keywords: aeroallergen; eosinophilic esophagitis; food bolus impaction; food bolus obstruction; gastroscopy; season