• irritable bowel syndrome
• infection
• mental health
• prognosis

Chaudhary and Truelove were amongst the first to recognise that a proportion of patients with irritable bowel syndrome (IBS) report an apparent association between the onset of symptoms and a dysenteric illness.¹ The concept of “post-dysenteric IBS” (PD-IBS) has now been widely accepted with claims suggesting that it accounts for anything up to 25% of the totality of the condition. However, careful questioning of these patients sometimes, but not always, suggests that they may have had a “forme fruste” of the disorder before their infection, raising the possibility that there may be two forms of the illness, one being an exacerbation of a pre-existing disorder and another where the condition appears to arise de novo. Ultimately, issues surrounding the natural history of PD-IBS will only be resolved by detailed prospective and retrospective studies, such as the one reported by Neal and colleagues² in this issue of Gut[see page 410].

Given that dysentery leads to irritable bowel symptoms, what mechanisms might be responsible? Do the dysenteric organisms cause the problem directly, and if so, are some more noxious than others? Alternatively, does the resulting diarrhoea lead to a form of non-specific sensitisation? …