Introduction Eosinophilic oesophagitis (EoE), a disorder characterised by intermittent dysphagia, was first described over 20 years ago. The true prevalence of this condition is not known. In 2010, the British Society of Gastroenterology (BSG) established a National EoE Register. The aim was to determine the frequency and pattern of diagnosis in the UK, and to identify centres for future research and areas where few patients are diagnosed and hence educational input may be beneficial. We report the data collected from March 2010 to January 2012.

Methods A web-based register was established under the direction of the Oesophageal section of the BSG. Data entry was voluntary, anonymised, available by open access and did not require membership of the BSG. Clinicians from each hospital entered patient data. The date of birth and first part of patients' postcodes were recorded for demographic purposes and to prevent data duplication. Details of the specialty that made the diagnosis, the duration and pattern of symptoms, the diagnostic criteria and any treatment given were also recorded.

Results Data relating to 315 patients, although incomplete in some cases, were available for analysis. There were 229 patients from five centres and 86 patients from 30 other centres. No patients were entered from 70 hospitals. Their age ranged from 0 to 85 years. There were 236 males (75%) and 77 females (3:1). Symptom duration ranged from 0 to ≥25 years. 249 (79.0%) patients had >15 eosinophils per high power field (eos/hpf), 11 (4%) had <15 eos/hpf with 55 (17%) patients having no eosinophil count recorded. The main presenting complaints were: dysphagia in 250 patients (79%), food bolus obstruction in 127 (40%) and heartburn in 59 (19%). Endoscopy appeared normal in 47 (15%) or consistent with reflux oesophagitis in 25 (8%). In the remaining 243 (77%) there were specific signs suggestive of EoE: strictures in 43, Schatzki ring in 10, white exudates in 16 and rings, trachealisation or furrows in the remainder.

Conclusion This is one of the world's largest registers of EoE. Dysphagia or food bolus obstruction are the most common symptoms. Endoscopic abnormalities suggestive of EoE are common but 23% do not have endoscopic signs to suggest EoE and therefore biopsy of all patients with dysphagia should be performed regardless of endoscopic appearance. There is variable reporting of EoE in the UK. Several centres had sufficient patients to facilitate research on diagnosis and treatment. However it is uncertain, for those hospitals that did not enter any patients, whether no patients with EoE were diagnosed or whether patients were diagnosed but not entered into the register.

Competing interests None declared.