The development of a reliable biomarker for irritable bowel syndrome (IBS) remains one of the major aims of research in functional gastrointestinal disorders, and is complicated by the absence of a perfect reference standard.
Previous efforts based on genetic and immune markers have showed promise, but have not been robust.
Professor Jones and colleagues from Australia evaluated an extensive panel of gene expression and serology markers combined with psychological measures in differentiating IBS from health and between subtypes of IBS.
Of subjects eligible for analysis, 168 met criteria for IBS, while 76 were free of any functional gastrointestinal disorders.
The researchers selected a total of 34 markers based on pathways implicated in pathophysiology of IBS or whole human genome screening.
|Performance of a combination of 34 markers was good in differentiating IBS from health|
|Alimentary Pharmacology & Therapeutics|
Psychological measures were recorded that covered anxiety, depression and somatization.
Models differentiating disease and health were based on unconditional logistic regression and performance assessed through area under the receiver-operator characteristic curve (AUC), sensitivity and specificity.
The research team found that the performance of a combination of 34 markers was good in differentiating IBS from health, and was improved considerably with the addition of 4 psychological markers.
Of the 34 markers considered, discrimination was derived largely from a small subset.
The research team also obtained good discrimination between IBS subtypes with the best being observed for IBS-C vs. IBS-D.
However, the team observed that psychological variables provided almost no incremental discrimination subtypes over biological markers.
Professor Jones and team conclude, "A combination of gene expression and serological markers in combination with psychological measures shows exciting progress towards a diagnostic test for IBS compared with healthy subjects, and to discriminate IBS-C from IBS-D."