The University of Adelaide study, published in the international journal Gut, found that patients with diarrhoea-predominant IBS-D had fatigued T-cells.
Lead researcher Patrick Hughes said the South Australia discovery had an important role in helping scientists characterise the different types of IBS.
“A lot of people group patients with diarrhoea-dominant IBS with constipation-dominant IBS patients and they are almost different diseases,” he said.
“This (study) could help us figure how out how to better diagnose it but there is more research needed to come up with a treatment.”
Previous studies have shown that the immune system was more active in patients with IBS than in healthy people. They had also shown how cortisol and stress hormones inhibit the immune system.
“Others studies were always cross sectional but we followed our patients along the way and for the first time can show how people with diarrhoea dominant IBS associated end up with tired out and ‘out of puff’ T-cells,” Dr Hughes said.
In a world first, researchers followed South Australian patients for a year, comparing blood samples taken when a patient experienced symptoms and when they were symptom free.
Based on previous research, it was expected that patient T-cells would be more aggravated when they displayed symptoms.
However, the immune system was inhibited and the T-cells did not proliferate as well or give out certain mediators.
“IBS is terrible and affects about 10 per cent of the world’s population,” Dr Hughes said.
The study also included researchers from the South Australian Health and Medical Research Institute (SAHMRI) and was supported by the National Health and Medical Research Council (NHMRC).
Last year, they developed IBS pain relief medication using tarantula venom.
South Australia has three long-standing public universities, Flinders University, University of South Australia and the University of Adelaide, each of which are consistently rated highly in the international higher education rankings.Jump to next article