The differential diagnosis between eosinophilic esophagitis (EoE) and gastroesophageal reflux disease (GERD) is often challenging. We recently showed that the ALOX15 protein is expressed in 95% of esophageal biopsies from patients with a definitive diagnosis of EoE. Here we correlated ALOX15 expression with the clinical classification of EoE or GERD in a cohort of consecutive pediatric patients (n = 62) with at least 1 esophageal biopsy containing at least 15 eosinophils per high-power field (eos/HPF). The patients were categorized into the following groups: (1) at least 15 eos/HPF in the distal esophagus only (n = 24), (2) at least 15 eos/HPF in the proximal esophagus only (n = 5), and (3) at least 15 eos/HPF in the distal and proximal biopsies (n = 33). Control groups included patients with GERD with biopsies containing 6 to 15 eos/HPF (n = 9), patients with GERD with 5 eos/HPF or less (n = 15), patients with candida esophagitis (n = 15), and patients with normal biopsies (n = 15). ALOX15 was positive in 90.5% of patients with EoE (13/16 in group 1, 4/4 in group 2, 31/33 in group 3) versus 44% of patients with GERD (4/8 in group 1, 0/1 in group 2, and 0/0 in group 3), 2 of 9 (22%) of patients with 6 to 15 eos/HPF, and was negative in all patients with GERD with biopsies containing 5 eos/HPF or less, all patients with candida esophagitis, and all normal controls. In conclusion, ALOX15 is a sensitive marker of EoE; however, subpopulations of patients with GERD with >5 eos/HPF also express ALOX15. Positive ALOX15 expression is more prevalent in EoE than in GERD and may prove to be a useful diagnostic marker in patients with discrepant biopsy findings between the proximal and distal esophagus.
- Eosinophilic esophagitis
ASJC Scopus subject areas
- Pathology and Forensic Medicine