Microscopic colitis is an inflammatory bowel disease (IBD) that leads to chronic, watery diarrhoea. First believed to be rare, microscopic colitis has received more attention in recent decades, resulting in increasing incidence rates that exceed those of classic IBD in some countries. Hopefully, it is common practice nowadays to refer patients with chronic diarrhoea for a colonoscopy with biopsy samples taken, as this is the only way to diagnose microscopic colitis. Histology results distinguish between the subtypes of microscopic colitis — lymphocytic colitis, collagenous colitis and the more recently introduced incomplete microscopic colitis.

Chronic gastritis is a common condition that occurs when an inflammatory infiltrate is present in the gastric mucosa. Diverse factors can cause such inflammation to develop, including food, common bacteria (particularly Helicobacter pylori) and even some viruses. Although the inflammatory infiltrate itself may not cause a disease per se, in some cases gastritis will evolve into atrophic gastritis, ulcers or gastric cancer. Clinicians therefore need to be aware of when gastritis is a harmless condition that can be left alone and when further action is required. In addition, many patients and some clinicians use the term ‘chronic gastritis’ to describe symptoms, mostly those of dyspepsia. This misuse of the terminology can lead to the erroneous conclusion that a diagnosis is being discussed and not a symptom. Here we address these mistakes and some of the others that are frequently made when managing patients with chronic gastritis. We discuss how to avoid making the mistakes to ensure that patients are managed adequately while reducing over treatment.