Medically reviewed by Onikepe Adegbola, MD, PhD
A recent clinical study from the UK supports the 2017 North Atlantic Consensus (NAC) Recommendations for diagnosing small intestinal bacterial overgrowth (SIBO) and carbohydrate malabsorption using breath hydrogen and methane testing. This study titled “Performance and Interpretation of Hydrogen and Methane Breath Testing Impact of North American Consensus Guidelines” was published in Digestive Diseases and Sciences.
The 2017 NAC recommendations for diagnosing SIBO and carbohydrate malabsorption were mainly based on expert opinion. This study provides clinical data supporting the expert recommendations and indicates that the experts were right all along.
In the 2017 recommendations, experts had recommended decreasing the dose of ingested lactulose (from 16g to 10g) and increasing the dose of glucose (from 50g to 75g) in breath testing protocols for diagnosing SIBO. Also, they had recommended increasing the time for analysis from 120 minutes to 180 minutes for diagnosing carbohydrate malabsorption.
This study included data on 725 patients tested for SIBO and carbohydrate malabsorption with different breath testing protocols. The authors compared the accuracy of the diagnosis made using pre-2017 and post-2017 protocols based on NAC guidelines.
Importantly, the results of this study correlated the results of breath testing with the provoked symptoms occurring after ingesting the carbohydrate load. The authors report that the diagnosis made using the 2017 NAC guidelines for breath hydrogen and methane testing was more accurate and patient-friendly than that reached using the pre-2017 protocols.
The diagnostic accuracy improved when the 2017 NAC diagnostic criteria were combined with the earlier Ledochowski parameters.
Why Is This Study Important for Patients with Gut Symptoms
Patients with non-specific gut symptoms, such as bloating and abdominal discomfort after eating, are frequently evaluated in the clinic for SIBO and carbohydrate malabsorption by using breath hydrogen and methane testing.
However, there are several problems with the pre-2017 breath testing protocols, such as patient discomfort and inaccurate diagnosis. Thus, experts have agreed to revise the testing protocols in 2017 to solve those problems. However, large sets of clinical data do not support these recommendations. This study provided high-quality clinical data in support of the 2017 NAC recommendations.
This study’s results can provide the necessary push to universalize the clinical adoption of 2017 NAC recommendations for diagnostic breath testing for SIBO and carbohydrate malabsorption. Thus, these findings supporting the 2017 NAC recommendations and the combined use of 2017 NAC diagnostic criteria with Ledochowski parameters can potentially increase the diagnostic accuracy and improve the patient experience for those undergoing breath testing.
Detection of SIBO and carbohydrate metabolism in the clinic remains challenging in terms of breath testing accuracy and patient experience. The implementation of the 2017 NAC recommendations can potentially improve the process and outcomes of breath testing for SIBO and carbohydrate malabsorption.
Pitcher, C. K., Farmer, A. D., Haworth, J. J., Treadway, S., & Hobson, A. R. (2022). Performance and Interpretation of Hydrogen and Methane Breath Testing Impact of North American Consensus Guidelines. Digestive diseases and sciences, 10.1007/s10620-022-07487-8. Advance online publication. https://doi.org/10.1007/s10620-022-07487-8