Insights into the emerging epidemic of eosinophilic oesophagitis.

Eosinophilic oesophagitis (EOE) is a relatively recently recognised condition characterised by an increase in oesophageal eosinophils. EOE occurs in children and adults with a strong male preponderance. There has been a sharp increase in EOE in North America, Europe and Australia. The reasons for this increase remain unclear but are likely to be influenced by genetic and environmental factors, as well as early-life exposures. Based on recent population-based data, the estimated EOE prevalence in the USA is 56.7 per 100,000 persons. The peak prevalence was observed in patients between 35 and 39 years of age. Prevalence figures in Asia and the Middle East generally appear to be lower than in Western countries, but population-based studies are not available. A causal association between coeliac disease and EOE appears unlikely. Data on the seasonal variation of EOE remain inconclusive. Further population-based studies are needed to define the epidemiology of EOE.