Manning criteria

Overview

The Manning criteria are a set of clinical guidelines developed in the late 1970s to aid in the diagnosis of irritable bowel syndrome (IBS), a functional gastrointestinal disorder characterized by chronic abdominal discomfort and altered bowel habits. The criteria were named after Dr. Adrian Manning, who proposed them following a study that aimed to differentiate IBS from organic gastrointestinal diseases based on patient-reported symptoms.

Although newer diagnostic tools such as the Rome criteria (Rome III and Rome IV) have largely replaced the Manning criteria in clinical practice, the Manning criteria remain historically significant and are still referenced for educational purposes and in certain clinical settings. The criteria are based on the presence of specific gastrointestinal symptoms and the number of these symptoms correlates with the likelihood of having IBS.

Causes

The Manning criteria do not define the cause of irritable bowel syndrome but are used to identify it based on symptoms. However, IBS itself is believed to arise from a multifactorial combination of:

• Altered gut motility: Irregular muscle contractions in the intestines.

• Visceral hypersensitivity: Increased sensitivity of the intestines to normal digestive activity.

• Post-infectious changes: IBS may develop following gastroenteritis or food poisoning.

• Gut-brain axis dysregulation: Abnormal communication between the digestive system and central nervous system.

• Psychosocial factors: Stress, anxiety, and depression may contribute to or worsen symptoms.

• Changes in gut microbiota: An imbalance in the normal bacterial flora may play a role.

IBS is a diagnosis of exclusion, meaning other organic causes must be ruled out before applying the Manning or Rome criteria.

Symptoms

The Manning criteria consist of six core symptoms, with the likelihood of IBS increasing as more symptoms are present. The original criteria include:

1. More frequent stools at the onset of pain

2. Looser stools at the onset of pain

3. Pain relieved by defecation

4. Visible abdominal bloating

5. Sensation of incomplete evacuation

6. Mucus passed in stools

Typically, having at least three or more of these symptoms strongly suggests IBS, especially in the absence of "alarm features" like weight loss, rectal bleeding, anemia, or nocturnal symptoms. The symptoms are chronic, fluctuate over time, and are often triggered or worsened by food intake and stress.

Diagnosis

The Manning criteria are used as part of a symptom-based approach to diagnosing IBS. Diagnosis includes the following steps:

• Detailed clinical history: Focused on symptom patterns, duration, triggers, and relieving factors.

• Application of the Manning criteria: Identification of the number and nature of symptoms present.

• Exclusion of organic diseases:

  • Basic blood tests (CBC, CRP)

  • Stool tests (to rule out infection or inflammation)

  • Colonoscopy or imaging if alarm features are present or if the patient is over 50 years of age

• Comparison with other diagnostic criteria: While the Rome IV criteria are now the standard, the Manning criteria may be used as supportive diagnostic evidence.

The Manning criteria are particularly useful in primary care settings and for initial assessments when access to extensive diagnostics may be limited.

Treatment

Treatment for IBS, as identified using the Manning criteria, focuses on symptom management and improving quality of life. It includes:

• Dietary modifications:

  • Low FODMAP diet (fermentable oligo-, di-, monosaccharides and polyols)

  • Increased fiber intake (soluble fiber preferred)

  • Avoiding trigger foods (dairy, caffeine, spicy foods)

• Pharmacologic therapies:

  • Antispasmodics (e.g., hyoscine, dicyclomine) for abdominal cramps

  • Laxatives for IBS with constipation (IBS-C)

  • Anti-diarrheal agents like loperamide for IBS with diarrhea (IBS-D)

  • Tricyclic antidepressants or SSRIs for pain and associated mood symptoms

  • Probiotics in some cases

• Psychological therapies:

  • Cognitive behavioral therapy (CBT)

  • Mindfulness-based stress reduction

  • Gut-directed hypnotherapy

• Regular exercise: Shown to improve overall gastrointestinal function and reduce stress.

Treatment should be individualized based on the predominant symptoms (constipation, diarrhea, or mixed) and the patient’s response to various interventions.

Prognosis

Irritable bowel syndrome, as diagnosed using the Manning criteria, is a chronic but non-life-threatening condition. While it does not increase the risk of cancer or shorten lifespan, it can significantly affect a person's quality of life due to its persistent and unpredictable symptoms.

With appropriate lifestyle changes, dietary management, and symptom-targeted therapies, most patients can manage their symptoms effectively. The prognosis improves when care is multidisciplinary, and patients receive education and psychosocial support. For some individuals, symptoms may remit entirely, while others may experience relapsing and remitting courses throughout life.

Early diagnosis using criteria like Manning or Rome can reduce unnecessary investigations and improve treatment outcomes through targeted, patient-centered care.