Eosinophilic oesophagitis (EoE) is a chronic immune-mediated inflammatory condition that is confined to the oesophagus. Clinically, EoE is characterized by symptoms of oesophageal dysfunction; histologically, by eosinophil-predominant inflammation.1,2 At present, EoE is the second-most frequent cause of chronic oesophagitis (gastro-oesophageal reflux disease [GORD] is the primary cause) and the foremost cause of dysphagia and food impaction in young adults and children.

Diarrhoea, acute or chronic, is a common gastrointestinal symptom in healthcare. In most cases, acute diarrhoea in healthy individuals requires limited diagnostic and therapeutic efforts, except for the replacement of fluid electrolytes, and stool culture in severe occurrences. Acute diarrhoea is often self-limiting due to short-lived reactions to food intake and bacterial or viral infections. However, diarrhoea can persist and fulfil definitions of chronicity when a month or more has passed since the onset. Here we discuss some basic mistakes that should be avoided when managing unexplained non-bloody diarrhoea that persists beyond the acute setting. In this context, the term 'unexplained' refers to a patient without apparent alarm features and where initial consultations have failed at making a diagnosis. We used an evidence-based approach and included aspects predominantly based on clinical experience when appropriate.