We read with interest the article by Sealock et al., which reports the low prevalence of oesophageal eosinophilia (2.3%) among a large series of unselected patients undergoing upper gastrointestinal (GI) endoscopy. Possibly, the rate of oesophageal eosinophilia has been underestimated in this study as a consequence of the oesophageal biopsy protocol.
More than 90% of cases and controls had only one biopsy from the distal oesophagus, which is not in accordance with current consensus recommendations made due to the patchiness of eosinophilic oesophagitis (EoE) (two to four mucosal biopsy specimens of the proximal and distal oesophagus should be obtained). This limitation is acknowledged by the authors in their discussion.
Nevertheless, this manuscript sheds light on the importance of performing routine oesophageal biopsies to detect EoE exclusively in patients with symptoms of oesophageal dysfunction (food bolus impaction, dysphagia or chest pain). The prevalence of oesophageal eosinophilia has been recently reported to be as low as 1.1% in a population study, 0.9% or 4% in patients with refractory gastro-oesophageal reflux disease, and 4.9% or 6.5% in patients presenting for endoscopy with upper GI symptoms.
Similarly, an atopic background[5-7] has been lately characterised as a predictor of oesophageal eosinophilia in the aforementioned patients. Nonetheless, the relevance of this histopathological finding in patients with no oesophageal dysfunction remains unknown.
This article provides a relevant clinical message: oesophageal biopsies should only be taken when there is clinical suspicion of EoE. Hence, increased awareness of an emerging disease such as EoE should not lead to an increase in the rate of unnecessary oesophageal biopsies.