A Diagnosis of Irritable Bowel Syndrome Using Rome IV Criteria and Limited Investigations is Durable in Secondary Care

BACKGROUND & AIMS: Irritable bowel syndrome (IBS) is a positive diagnosis, made using symptom-based criteria and limited, judicious, investigation. However, this may lead to uncertainty on the part of clinicians regarding potential for a missed diagnosis of organic gastrointestinal disease. Few studies have examined durability of a diagnosis of IBS, and none have used the current gold standard to diagnose IBS, the Rome IV criteria. METHODS: We collected complete symptom data from 373 well-characterized adults meeting Rome IV criteria for IBS referred to a single UK clinic between September 2016 and March 2020. All patients underwent relatively standardized work-up to exclude relevant organic disease before diagnosis. We followed these individuals up to December 2022, assessing rates of rereferral, reinvestigation, and missed organic gastrointestinal disease. RESULTS: During a mean follow-up of 4.2 years per patient (total follow-up in all patients, 1565 years), 62 (16.6%) patients were rereferred. Of these, 35 (56.5%) were rereferred for IBS and 27 (43.5%) for other gastrointestinal symptoms. Among the 35 rereferred with IBS this was caused by a change in symptoms in only 5 (14.3%). Reinvestigation was undertaken in 21 (60.0%) of 35 rereferred with IBS and 22 (81.5%) of 27 rereferred with other symptoms (P [ .12). Only 4 (9.3% of those reinvestigated and 1.1% of the entire cohort) new cases of relevant organic disease, which may have been responsible for IBS symptoms at baseline, were identified (1 case of chronic calcific pancreatitis among those rereferred with IBS and 1 case each of inflamma-tory bowel disease-unclassified, moderate bile acid diarrhea, and small bowel obstruction among those rereferred with other gastrointestinal symptoms). CONCLUSIONS: Despite rereferral for gastrointestinal symptoms among 1 in 6 patients overall, with almost 10% rereferred with ongoing IBS symptoms, and substantial reinvestigation rates, missed organic gastrointestinal disease occurred in only 1%. A diagnosis of Rome IV IBS after limited investigation is safe and durable.