Considerations for undiagnosed patients

Healthcare professional holding a tablet while speaking with a patient

Distinguishing IBD from IBS

Key differences

Inflammatory bowel disease (IBD)

A chronic inflammatory disorder where the immune system causes inflammation and damage in the GI tract.

Irritable bowel syndrome (IBS)

A functional bowel disorder that does not cause inflammation or permanent damage to the GI tract.

Comorbidity

IBD and IBS

Patients may have both IBD and IBS. Although the exact prevalence of comorbid IBD and IBS is not precisely known, a meta-analysis has estimated it to be 39%.

The American Gastroenterological Association (AGA) has clinical practice guidelines on diagnosing and treating patients with both functional GI symptoms (such as IBS) and IBD

Fecal calprotectin testing

Recommended to help differentiate IBD from IBS and can be useful in the primary care setting. In patients with lower GI symptoms where cancer is not suspected, a low/normal fecal calprotectin may indicate IBS, while a high fecal calprotectin may indicate IBD.

Comparison table

The table below highlights similarities and differences between IBD and IBS and can be useful for primary care clinicians in patients presenting with GI symptoms.

IBD vs IBS: What is the difference?

	IBD	IBS
Symptoms	Diarrhea Abdominal pain Cramping Bowel urgency with or without incontinence Nocturnal bowel movements Increased bowel frequency Bloody stool Weight loss Joint pain Anemia Blood in the stool, nocturnal bowel movements, weight loss, and joint pain are more common in IBD than IBS.	Symptoms often occur after eating a large meal or when under stress and may include: Diarrhea Abdominal pain Cramping Abdominal distension Constipation Mucus in stool Gas
Laboratory/diagnostic test results	Anemia may be present Elevated fecal calprotectin Inflammation of bowel wall seen on imaging Redness, ulceration, bleeding seen with endoscopies	Anemia not present Normal fecal calprotectin No inflammation seen on imaging or endoscopies
Treatment	Treatment targeted to reduce inflammation and help control symptoms	Treatment to help relieve symptoms but there is no one medication that works for all