Diagnosis and management of irritable bowel syndrome

Irritable bowel syndrome (IBS) is a disorder of gut-brain interaction characterised by recurrent abdominal pain or discomfort that is often related to defaecation or associated with a change in stool frequency or form. IBS is common in Australia and affects women more than men. The exact pathophysiology remains unclear, though it can be multifactorial and relate to gastrointestinal dysmotility, post-infection and microbial changes, and a patient's psychosocial background. A positive clinical diagnosis can be made when the Rome V criteria are met, alarm features are absent and simple screening tests (full blood count, C-reactive protein, coeliac serology) are negative. If alarm features are present, further examination, laboratory testing or imaging may be helpful in assessing for organic pathology. Management involves lifestyle and dietary modifications, and psychological and pharmacological therapies. Pharmacological therapy should be individualised to the patient's IBS subtype and symptoms. Examples of drug classes that are used include antispasmodics, osmotic laxatives, antidiarrhoeal drugs and neuromodulators (tricyclic antidepressants). There is insufficient evidence to support the use of therapies such as probiotics, faecal microbiota transplantation, and mesalamine.