What are the most recent Rome diagnostic criteria for functional gastrointestinal disorders, including Irritable Bowel Syndrome (IBS), Functional Dyspepsia (FD), and Functional Constipation, in adults?

Rome IV Diagnostic Criteria for Functional Gastrointestinal Disorders

The Rome IV criteria, released in May 2016, are the current gold standard for diagnosing functional gastrointestinal disorders (now termed "disorders of gut-brain interaction"), though clinicians should use the modified 8-week clinical criteria for routine practice rather than the restrictive 6-month research criteria. 1, 2

Critical Timing Consideration for Clinical Practice

For routine clinical use, the Rome Foundation developed less restrictive "clinical criteria" requiring only 8 weeks of cardinal symptoms, rather than the research-based requirement of 3 months of active symptoms with onset 6 months prior to diagnosis. 1, 2 The 6-month requirement was acknowledged as too restrictive and potentially delays diagnosis and treatment. 1

Irritable Bowel Syndrome (IBS)

Rome IV Diagnostic Criteria

IBS requires recurrent abdominal pain at least 1 day per week in the last 3 months (or 8 weeks for clinical criteria), with symptom onset at least 6 months before diagnosis, associated with two or more of the following: 3, 2, 4

• Pain related to defecation (can worsen OR improve with bowel movements, not just improve as in Rome III) 5
• Change in stool frequency 3, 2
• Change in stool form/appearance 3, 4

Key Changes from Rome III

• "Discomfort" was eliminated because it is non-specific and has different meanings across languages—only pain is now required 5
• Pain relationship to defecation was broadened to include worsening with bowel movements, not just improvement 5
• Rome IV is substantially more restrictive, reducing global IBS prevalence from 10.1% to 4.1%, with approximately 50% of Rome III patients no longer qualifying 3, 2
• Rome IV identifies patients with more severe symptoms and higher psychological comorbidity 3, 2

IBS Subtypes

IBS is classified based on predominant stool pattern into: IBS with constipation (IBS-C), IBS with diarrhea (IBS-D), mixed IBS, and unsubtyped IBS. 4 These functional bowel disorders are now viewed as existing on a continuum rather than as independent entities. 5, 6

Functional Dyspepsia (FD)

Rome IV Diagnostic Criteria

FD requires one or more of the following bothersome symptoms (severe enough to impact usual activities) present for the last 3 months (or 8 weeks for clinical criteria), with symptom onset at least 6 months before diagnosis, AND no structural disease on upper endoscopy to explain symptoms: 1, 3, 2

• Bothersome epigastric pain 1, 3
• Bothersome epigastric burning 1, 3
• Bothersome postprandial fullness 1, 3
• Bothersome early satiation 1, 3

Upper endoscopy is required by definition to exclude structural disease—approximately 80% of patients with dyspepsia symptoms will have functional dyspepsia after endoscopy. 2

FD Subtypes

Epigastric Pain Syndrome (EPS)

Must include one or both at least 1 day per week: 1, 3, 2

• Bothersome epigastric pain 1, 3
• Bothersome epigastric burning 1, 3

Supportive criteria: Pain may be induced by meals, relieved by meals, or occur while fasting; postprandial bloating, belching, and nausea can coexist; heartburn is not a dyspeptic symptom but may coexist; symptoms relieved by evacuation of feces or gas should not be considered dyspepsia. 1

Postprandial Distress Syndrome (PDS)

Must include one or both at least 3 days per week: 1, 3, 2

• Bothersome postprandial fullness (severe enough to impact usual activities) 1, 3
• Bothersome early satiation (severe enough to prevent finishing a regular-sized meal) 1, 3

Supportive criteria: Postprandial epigastric pain/burning, bloating, excessive belching, and nausea can coexist; vomiting warrants consideration of another disorder; heartburn may coexist but is not dyspeptic; symptoms relieved by feces/gas evacuation should not be considered dyspepsia. 1

Functional Constipation

Rome IV Diagnostic Criteria

Rome IV categorizes chronic constipation into four subtypes: 7

• Functional constipation 7
• Irritable bowel syndrome with constipation 7
• Opioid-induced constipation (new in Rome IV) 5, 7
• Functional defecation disorders (inadequate defecatory propulsion and dyssynergic defecation) 7

The specific diagnostic criteria follow the same temporal framework: symptoms for the last 3 months with onset at least 6 months prior (or 8 weeks for clinical use). 7

Functional Abdominal Bloating and Distention

Rome IV created a separate category for abdominal bloating and distention as a primary disorder, with global prevalence as high as 3.5% (4.6% in women, 2.4% in men). 3 When these criteria are met, the patient should NOT fulfill criteria for IBS, functional constipation, functional diarrhea, or functional dyspepsia. 3 Bloating and distention are much more prevalent (>50%) when associated with other disorders of gut-brain interaction. 3

New Disorders in Rome IV

Rome IV introduced new disorders fitting the definition of disorders of gut-brain interaction: 5

• Opioid-induced gastrointestinal hyperalgesia 5
• Opioid-induced constipation 5
• Cannabinoid hyperemesis 5
• Reflux hypersensitivity 5
• Centrally mediated abdominal pain syndrome 5

Red Flags Requiring Investigation

Warning signs mandating investigation regardless of age include: 3, 2

• Weight loss 3, 2
• Rectal bleeding 3, 2
• Nocturnal symptoms 3, 2
• Anemia 3, 2

Clinical Predictors Supporting Functional Diagnosis

The diagnosis is more likely if: 3, 4

• Female sex 3, 4
• Age <45 years with symptom history >2 years 3, 4
• Frequent past healthcare visits for non-gastrointestinal symptoms 3, 4

Important Clinical Pitfalls

Functional disorders frequently overlap with each other, which significantly reduces diagnostic sensitivity. 8 In validation studies, diagnostic sensitivity was 62.7% for IBS, 54.7% for FD, and only 32.2% for functional constipation, with excess overlap being a major contributor. 8 When overlap of IBS with functional constipation was permitted, sensitivity for constipation diagnosis increased to 73.2%. 8

Once a functional diagnosis is established using appropriate criteria and limited investigation, the incidence of new non-functional diagnoses is extremely low. 2, 4

Symptoms often fluctuate over time, and subtype classification may change. 4