16 Jun Could the gut microbiome predict NAFLD disease?
Exciting new research out of the University of California-San Diego (UCSD) has shown that a stool sample analysis of the gut microbiome may be able to better diagnose NAFLD.
-By Meghan Betts
Simple non-alcoholic fatty liver disease (NAFLD) is relatively benign, however, if left untreated it can progress into an advanced stage where additional liver inflammation can cause liver damage.
Advanced fibrosis, the thickening and scarring of connective tissue, is an important predictor for liver mortality. However, currently, there is no way to predict which patients with NAFLD will progress to the more advanced disease without an invasive liver biopsy.
Why the gut microbiome?
The gut microbiome encompasses the trillions of microbes that live in the gut together with their genetic material. Previous studies have shown that a person’s gut microbiome may affect their risk for obesity, thus the researchers investigated whether there is link between the gut microbiome and obesity-related liver disease such as NAFLD.
What did they do?
The study involved a total 86 confirmed NAFLD patients that had had a liver biopsy to classify the stage of their NAFLD as mild, moderate or advanced. The team of researchers used the patients stool samples to characterise the gut microbiome, including the presence, locations and relative abundance of various microbe species.
What did they find?
Interestingly, they identified 37 bacterial species that differentiated advanced stage NAFLD from the mild or moderate stages, at an accuracy of 93.6%. They validated this in a second group of 16 patients with advanced NAFLD and 33 healthy volunteers who acted as controls, and found that they could differentiate the NAFLD patients from healthy controls with 88% accuracy by studying the relative abundance of 9 species of bacteria, 7 of which were previously identified on the first study.
What does this mean?
With no current medications available for NAFLD, yet dozens in the pipeline, being able to better diagnose the disease and identify those who have or are at risk of developing NAFLD is a ‘critical unmet medical need’ says first author Rohit Loomba, UCSD. In turn, this could lead to better selection of patients for clinical trials aimed at preventing and treating the disease.
However, this study was only performed on a small number of patients, in a specialised setting, and further validations are required before a stool sample test could be available for clinical use. That being said, the study does show a ‘proof-of-concept’ with the potential to be a real benefit to patients.
“We believe our study sets the stage for a potential stool-based test to detect advanced liver fibrosis based simply on microbial patterns, or at least help us minimize the number of patients who have to undergo liver biopsies.”
Senior author Dr. Karen E. Nelson, president of the J. Craig Venter Institute