From the Guidelines
Stool studies are not the primary diagnostic tool for investigating abdominal bloating, and a breath test is more appropriate for suspected small intestinal bacterial overgrowth (SIBO). When evaluating abdominal bloating, it is essential to consider the underlying causes, which can include infections, inflammatory bowel disease, malabsorption syndromes, or functional disorders 1. The American Gastroenterological Association (AGA) Clinical Practice Update provides best practice advice for the evaluation and management of belching, abdominal bloating, and distention, emphasizing the importance of a multidisciplinary approach and patient-centered care 1. Some key points to consider in the diagnostic workup of abdominal bloating include:
- Clinical history and physical examination findings to differentiate between gastric and supragastric belching 1
- Rome IV criteria to diagnose primary abdominal bloating and distention 1
- Carbohydrate enzyme deficiencies may be ruled out with dietary restriction and/or breath testing 1
- Serologic testing to rule out celiac disease in patients with bloating 1
- Abdominal imaging and upper endoscopy should be ordered in patients with alarm features, recent worsening symptoms, or an abnormal physical examination only 1 Breath testing is the preferred method for diagnosing SIBO, rather than stool testing 1. Additionally, psychological therapies, such as hypnotherapy, cognitive behavioral therapy, and other brain–gut behavior therapies, may be used to treat patients with bloating and distention 1. It is crucial to identify the underlying cause of bloating to provide targeted treatment, rather than just managing symptoms, as bloating can result from various conditions, including infections, inflammatory bowel disease, malabsorption syndromes, or functional disorders 1.
From the Research
Stool Studies for Abdominal Bloating
- Abdominal bloating is a common symptom associated with functional gastrointestinal disorders or organic diseases, and its pathophysiology remains ambiguous 2, 3.
- The mechanisms involved in bloating include gut hypersensitivity, impaired gas handling, altered gut microbiota, and abnormal abdominal-phrenic reflexes 2, 4.
- Stool studies, such as gas transit studies, have shown that patients with bloating have impaired reflex control of gut handling of contents, leading to segmental pooling of gas or solid/liquid components 3.
- Faecal immunochemical tests (FIT) can help rule out colorectal cancer in patients presenting with lower abdominal symptoms, but their role in diagnosing bloating is limited 5.
- Diagnostic approaches to bloating include evaluating symptoms, classifying patients into different categories (e.g., gastric bloating, small bowel bloating), and using noninvasive tests, such as FIT, to rule out underlying conditions 6.
- Management of bloating includes dietary interventions, behavioral therapy, microbiome modulation, and medical therapy, with empiric therapy being a reasonable initial approach 4, 6.