Bile acid diarrhoea: pathophysiology, diagnosis and management

Area of Science:

• Gastroenterology
• Hepatology
• Digestive Diseases

Background:

• Bile acid diarrhoea (BAD) is increasingly recognized but often misdiagnosed, particularly in patients with irritable bowel syndrome.
• It can stem from hepatic overproduction or ileal malabsorption of bile acids, leading to symptoms like urgency and incontinence.
• Triggers include cholecystectomy, infections, and pelvic chemoradiotherapy, with potential gut microbiota involvement.

Purpose of the Study:

• To highlight the diagnostic challenges and clinical impact of bile acid diarrhoea.
• To discuss the pathophysiology involving bile acid synthesis regulation and enterohepatic circulation.
• To explore current and emerging diagnostic methods for BAD.

Main Methods:

• Review of existing literature on bile acid diarrhoea pathophysiology and diagnosis.
• Discussion of diagnostic tools including SeHCAT scans, blood tests, stool, and urine bile acid measurements.
• Exploration of the role of farnesoid X receptor and fibroblast growth factor 19 in bile acid regulation.

Main Results:

• Up to 30% of diarrhoea-predominant IBS patients may have misdiagnosed BAD.
• Delayed diagnosis significantly impacts patient quality of life and increases diagnostic costs.
• Gut microbiota alterations are observed in severe BAD cases.

Conclusions:

• Accurate and timely diagnosis of BAD is essential to prevent prolonged suffering and healthcare expenditure.
• Further research into non-invasive diagnostic methods and understanding the gut microbiome's role is warranted.
• Recognizing BAD beyond IBS is critical for appropriate patient management.