From the Guidelines
The Rome IV criteria for Irritable Bowel Syndrome (IBS) are the most recent and widely accepted guidelines for diagnosing IBS, and they require recurrent abdominal pain at least one day per week in the last three months, with symptom onset at least six months prior to diagnosis, as outlined in the British Society of Gastroenterology guidelines 1.
Key Criteria
The Rome IV criteria specify that the abdominal pain must be associated with at least two of the following:
- Related to defecation
- Associated with a change in stool frequency
- Associated with a change in stool form or appearance These criteria help distinguish IBS from other functional gastrointestinal disorders, as noted in the guidelines 1.
Subtyping of IBS
IBS is further subtyped based on predominant stool patterns:
- IBS with predominant constipation (IBS-C)
- IBS with predominant diarrhea (IBS-D)
- IBS with mixed bowel habits (IBS-M)
- IBS unclassified (IBS-U) The Rome IV criteria represent a refinement from previous versions, emphasizing that pain must be present for diagnosis and removing the term "discomfort" due to its ambiguity across different languages and cultures 1.
Clinical Implications
The use of the Rome IV criteria has important clinical implications, as they are more specific for diagnosing IBS, but may also lead to a decrease in the number of patients diagnosed with IBS, with some patients being diagnosed with other functional bowel disorders instead 1.
Diagnosis and Treatment
These criteria help clinicians make a positive diagnosis of IBS rather than considering it solely a diagnosis of exclusion, though limited testing may still be warranted to rule out other conditions depending on the clinical presentation 1.
From the Research
Rome IV Criteria for IBS
The Rome IV criteria for Irritable Bowel Syndrome (IBS) involve several key changes from the previous Rome III criteria, including:
- The exclusion of discomfort (in contrast to pain) 2
- More stringent frequency criteria for pain to be eligible for diagnosis of IBS, specifically, on average, at least 1 day per week in the last 3 months 2, 3 Some key points about the Rome IV criteria include:
- The fundamental definition based on abdominal pain in association with bowel dysfunction has been consistent 2
- Validation studies of the consensus, symptom-based criteria have identified multiple deficiencies that question the rationale for "splitting" the different syndromes, and favor a simpler identification of the classical symptoms of abdominal pain, bowel dysfunction, and bloating, and exclusion of alarm symptoms 2
- Most Rome III-positive IBS patients seeking healthcare fulfil the Rome IV IBS criteria, and they constitute a more severe group than those who lose their IBS diagnosis 3
Clinical Characteristics and Pathophysiological Factors
The change in IBS criteria from Rome III to Rome IV impacts on clinical characteristics and pathophysiological factors, including:
- Demographics: Rome IV-positive subjects are significantly more likely to be female 3
- IBS subtype: No differences in IBS subtypes between Rome IV-positive and -negative subjects 3
- Gastrointestinal and psychological symptoms: Rome IV-positive subjects have greater pain severity, bloating, somatisation, fatigue, and rectal sensitivity than Rome IV-negative subjects 3
- Disease-specific quality of life: Rome IV-positive subjects have poorer quality of life than Rome IV-negative subjects 3
Diagnosis and Treatment
The diagnosis and treatment of IBS according to the Rome IV criteria involve:
- Identification of the classical symptoms of abdominal pain, bowel dysfunction, and bloating, and exclusion of alarm symptoms 2
- Treatment with medications such as loperamide, psyllium, bran, lubiprostone, linaclotide, amitriptyline, and rifaximin, among others 4, 5, 6
- Non-pharmacological treatment, including dietary interventions such as gluten elimination and low FODMAP diet 6