Non-oesophageal eosinophilic gastrointestinal diseases are undersuspected clinically and underdiagnosed pathologically

Background: Non-oesophageal gastrointestinal eosinophilic diseases (EGID) are considered rare. However, low disease awareness among clinicians and pathologists may contribute to underdiagnosis. Aims: To determine how frequently requests to evaluate for EGID accompany gastrointestinal biopsies and in what proportion of suspected cases pathologists address these requests, either confirming or refuting the clinical suspicion. Methods: All cases in which biopsy requisitions included an explicit suspicion of EGID were extracted from a large clinicopathologic database and manually reviewed for accuracy. The diagnoses for these cases were then analysed to determine whether clinical suspicions were confirmed, refuted or ignored. Results: Eosinophilic oesophagitis (EoE) was suspected in 12.8% of 903,516 patients with biopsies and confirmed in 14.9% of them. A suspicion of eosinophilic gastritis accompanied <0.001% of 1,438,206 gastric biopsy sets and was confirmed in 11.5% of them; eosinophilic duodenitis was suspected in 0.02% of -675,519 patients with duodenal biopsies and confirmed in 8.0% of these; eosinophilic colitis was mentioned in <0.001% of 2,504,485 patients with colonic biopsies and confirmed in 0.1% of them. Less than 3% of endoscopists mentioned non-oesophageal EGID in the requisition, while most expressed a clinical suspicion of Barrett oesophagus, Helicobacter pylori gastritis, celiac disease and microscopic colitis (in 21.2%, 49.2%, 1% and 6.4% of the cases, respectively). Conclusions: Gastroenterologists and pathologists commonly address and diagnose EoE. In contrast, both clinical suspicion and diagnosis of non-oesophageal EGID are extremely rare. Increased clinical awareness might result in a better understanding of the epidemiology and improved diagnosis of these still elusive conditions.