Abdominal distention represents a prevalent clinical manifestation characterized by an unclear etiology and pathogenesis. This symptomatology is frequently observed in various conditions, including small intestinal bacterial overgrowth (SIBO) and abnormal orocecal transit time (OCTT). The utilization of the breath test as a non-invasive diagnostic approach has become widespread in recent years for identifying SIBO and abnormalities in OCTT. In this study, the prevalence of SIBO and OCTT irregularities in individuals presenting with abdominal distention was ascertained through the implementation of the breath test. Furthermore, the correlation between abdominal distention and SIBO/OCTT was analysed to enhance the elucidation of the underlying etiology of abdominal distention. These findings aim to offer valuable insights for refining clinical comprehension and strategies related to the diagnosis and treatment of abdominal distention.

Abdominal distention represents a prevalent clinical manifestation characterized by an unclear etiology and pathogenesis. And the prevalence of abdominal distension is high in the population. This symptomatology is frequently observed in various conditions, including small intestinal bacterial overgrowth (SIBO) and abnormal orocecal transit time (OCTT). The utilization of the breath test as a non-invasive diagnostic approach has become widespread in recent years for identifying SIBO and abnormalities in OCTT. In this study, the prevalence of SIBO and OCTT irregularities in individuals presenting with abdominal distention was ascertained through the implementation of the breath test. Furthermore, the correlation between the clinical features such as severity, location, and frequency of abdominal distension and SIBO/OCTT was analysed to enhance the elucidation of the underlying etiology of abdominal distention. These findings aim to offer valuable insights for refining clinical comprehension and strategies related to the diagnosis and treatment of abdominal distention.

Inclusion Criteria:

1. Patients aged 18 to 70 years.
2. Patients presenting with the primary complaint of abdominal bloating and/or abdominal distension, or those exhibiting abdominal distension with prominence over other symptoms.

Exclusion Criteria:

1. Patients who are pregnant or lactating.
2. Patients have history of gastrointestinal malignancy or gastrointestinal surgery.
3. Patients manifesting food intolerance or presenting with a confirmed diagnosis or suspicion of lactose intolerance.
4. Patients with urinary system (chronic kidney disease, etc.), immune system (scleroderma, etc.), nervous system (Parkinson's disease, etc.), mental system (depression, etc.), or other diseases outside the digestive system.
5. Patients who used antibiotics or microecological agents or underwent endoscopic examination within two weeks.
6. Patients with a medication history encompassing motility enhancers, secretory enhancers, antifoaming agents, spasmolytics, opioids, and antidepressants within the past week.
7. Patients who are unwilling or incapable to provide informed consents.

Abdominal distension patients in the outpatient department at Qilu Hospital of Shandong University.