The Optimal Number of Biopsy Fragments To Establish a Diagnosis of Eosinophilic Esophagitis
Jennifer A Nielsen, Donna J Lager, Matthew Lewin, Cory A Roberts. ProPath, Dallas, TX
Background: Eosinophilic esophagitis (EoE) is characterized clinically by dysphagia, chest pain and food impaction and morphologically by increased numbers of intraepithelial eosinophils and marked basal hyperplasia of the squamous mucosa. The consensus criteria for a diagnosis of EoE include the presence of > 15 eosinophils/HPF in biopsies from both proximal and distal esophagus in the absence of other causes of esophageal eosinophilia, and the lack of a clinical response to proton pump inhibitor therapy. Because of the variability in the distribution of intraepithelial eosinophils among biopsy fragments and the lack of standardized biopsy practices, we sought to determine the optimum number of esophageal biopsies from the mid and distal esophagus needed to make a diagnosis of EoE.
Design: From 1/5/2009 to 9/26/2011, 771 patients were diagnosed with EoE at our institution. From that patient population, biopsies from 45 sequential cases were chosen for further study. All of the 45 patients had biopsies from the mid and distal esophagus. Cases with only gastric mucosa present and biopsies from patients undergoing therapy for EoE were excluded. The original H&E-stained slides were reviewed, and the number of biopsy fragments containing squamous mucosa was recorded. Using a 40X objective and 10X oculars (field diameter = 0.52 mm, field area = 0.849 mm2), the number of eosinophils per high power field (EOS/HPF) in up to three HPF was counted in each biopsy fragment.
Results: The EOS/HPF was counted in 487 biopsy fragments. The number of biopsy fragments obtained from the mid esophagus ranged from 1 to 14 (mean 6; median 6) and from the distal esophagus from 1 to 15 (mean 5; median 5). There was no significant difference between the mean number of EOS/HPF from the mid (20.85) and lower (23.77) esophagus (p=0.29705, 2-tailed T-test). When the total number of biopsy fragments containing 1 to 10 and >10 EOS/HPF was calculated, 71.1% of cases with 3 biopsy fragments and 90.5% with >10 biopsy fragments had >15 EOS/HPF. The probability of 1, 4, 5 and >6 biopsy fragments containing > 15 EOS/HPF was .55, .96, .98 and >.99 respectively.
Conclusions: From this data at least 4 biopsy fragments should be submitted from mid and distal esophagus to optimize the chances of a positive diagnosis of EoE, however the yield is not increased beyond 6 biopsy fragments. Although there was no statistically significant difference in EOS/HPF between mid and distal esophagus, biopsy of both sites is necessary to exclude reflux esophagitis.
Monday, March 4, 2013 1:00 PM
Poster Session II # 107, Monday Afternoon