Ellen Phiddian
Cosmos science journalist
Endometriosis is a painful and very common condition, but it’s difficult to diagnose, sometimes taking years.
A team of US researchers think that it may one day be possible to diagnose endometriosis more quickly and easily with a stool test.
They’ve published a study in Med, which found that women with endometriosis had key differences in their gut microbiomes, compared to those who didn’t have the condition.
“Endometriosis develops when lining inside the womb grows outside its normal location, for instance attached to surrounding intestine or the membrane lining the abdominal cavity. This typically causes bleeding, pain, inflammation and infertility,” says corresponding author Dr Rama Kommagani, an associate professor at Baylor College of Medicine, USA.
“Generally, it takes approximately 7 years to detect endometriosis and is often diagnosed incorrectly as a bowel condition.”
Currently, endometriosis is diagnosed with a surgical procedure that treats the condition at the same time.
“Our previous studies in mice have shown that the microbiome, the communities of bacteria living in the body, or their metabolites, the products they produce, can contribute to endometriosis progression,” says Kommagani.
“In the current study, we took a closer look at the role of the microbiome in endometriosis by comparing the bacteria and metabolites present in stools of women with the condition with those of healthy women. We discovered significant differences between them.”
The team tested poo samples from 18 women who had endometriosis, and 31 women who didn’t.
They found a certain combination of metabolites (compounds made from broken-down food) was unique to endometriosis. These metabolite groups were similar to those of patients with inflammatory bowel disease.
One substance, called 4-hydroxyindole, was particularly indicative.
“This compound is produced by ‘good bacteria,’ but there is less of it in women with endometriosis than in women without the condition,” says first author Dr Chandni Talwar, a postdoctoral associate at Baylor.
“There are studies in animal models of the disease that have shown specific bacterial metabolite signatures associated with endometriosis.
“Our study is the first to discover a unique metabolite profile linked to human endometriosis, which brings us closer to better understanding the human condition and potentially identifying better ways to manage it.”
The team administered 4-hydroxyindole to mice, and found that it could prevent endometriosis-like inflammation from starting or progressing.
“These findings are very exciting,” says Talwar.
