What is the research on irritable bowel syndrome (IBS) symptoms in inflammatory bowel disease (IBD)?

From the Guidelines

Irritable bowel syndrome (IBS) symptoms commonly overlap with inflammatory bowel disease (IBD), with research showing that 30-50% of IBD patients experience IBS-like symptoms even during disease remission, and management includes a stepwise approach to rule-out ongoing inflammatory activity, as well as consideration of dietary modifications, stress reduction techniques, and medications targeting specific symptoms 1.

Diagnosis and Management

To diagnose IBD-IBS, it is essential to confirm IBD remission through biomarkers (calprotectin, CRP) and endoscopy while symptoms persist. The following steps can be taken:

• A stepwise approach to rule-out ongoing inflammatory activity should be followed in IBD patients with persistent GI symptoms (measurement of fecal calprotectin, endoscopy with biopsy, cross-sectional imaging) 1.
• In those patients with indeterminate fecal calprotectin levels and mild symptoms, clinicians may consider serial calprotectin monitoring to facilitate anticipatory management 1.
• Anatomic abnormalities or structural complications should be considered in patients with obstructive symptoms including abdominal distention, pain, nausea and vomiting, obstipation or constipation 1.

Treatment Options

Treatment options for IBD-IBS include:

• Dietary modifications, such as a low FODMAP diet for 4-8 weeks with reintroduction, which may help alleviate symptoms 1.
• Stress reduction techniques, such as cognitive behavioral therapy, hypnotherapy, or mindfulness therapy, which can help manage symptoms 1.
• Medications targeting specific symptoms, such as antispasmodics (dicyclomine 10-20mg three times daily), tricyclic antidepressants (amitriptyline 10-25mg nightly), or serotonin modulators (ondansetron 4-8mg as needed) 1.
• Probiotics containing Bifidobacterium may also help some patients 1. It is essential to note that these symptoms, while not indicating active inflammation, significantly impact quality of life and require a different treatment approach than IBD flares. Patients should be aware of this and work closely with their healthcare provider to develop an effective management plan.

From the Research

Research on Irritable Bowel Disease Symptoms in Inflammatory Bowel Disease

• The symptoms of irritable bowel syndrome (IBS) are frequently present in patients with inflammatory bowel disease (IBD), but the cause of this phenomenon is unclear 2.
• Studies have shown that IBS-type symptoms in IBD patients can be due to sub-clinical inflammation, but also may be similar to those experienced by people diagnosed with IBS in the general community 2.
• The presence of IBS-type symptoms in IBD patients can complicate diagnosis and management, as it may be difficult to determine whether the symptoms are due to IBD or IBS 3, 4.
• Research has identified some shared contributing factors between IBD and IBS, including genetic, microbiological, epithelial, and immunological factors 5.
• Some studies suggest that IBS-type symptoms in IBD patients may be triggered by IBD, or may represent a subtle level of IBD activity that is not recognized by available laboratory or imaging methods 3, 4.
• Treatment of IBD patients with IBS-type symptoms may involve a combination of therapies, including aminosalicylates, corticosteroids, and biologic agents 6.
• A systematic diagnostic approach is required to assess IBD patients with IBS-type symptoms, as sub-clinical inflammation may play a role in a proportion of cases 2.

Pathophysiology of Post-IBD IBS-D

• The pathophysiology of post-IBD IBS-D is not fully understood, but may involve alterations in mucosal inflammation, the microbiota, mucosal permeability, and gut-brain interactions 3.
• Some studies have suggested that post-IBD IBS-D patients may harbor significantly increased colon mucosal eosinophils, and may respond to a GI-hypoallergenic diet and budesonide therapy 3.
• Further research is needed to understand the pathophysiology of post-IBD IBS-D and to develop effective treatments for this condition 3.

Clinical Implications

• The presence of IBS-type symptoms in IBD patients can have significant clinical implications, including delayed diagnosis and treatment of IBD 4.
• A thorough diagnostic evaluation is necessary to determine the cause of IBS-type symptoms in IBD patients, and to develop an effective treatment plan 2.
• Clinicians should be aware of the potential for overlap between IBD and IBS, and should consider a functional approach for certain manifestations of IBD 5.