A study may have found that a effects on a key gut bacteria are the reason why some patients experience diarrhoea after receiving the widely prescribed antibiotic amoxicillin-clavulanate.
Researchers, reporting in the journal iScience, found that the level of gut Ruminococcaceae, which plays a role in maintaining an individual’s gut health, strongly impacts diarrhoeal outcomes following antibiotic treatment.
One in three patients prescribed amoxicillin-clavulanate will develop diarrhoea. In some cases, it may be so severe that doctors have to prematurely halt the antibiotic, inadequately treating the infection or else forcing a change in antibiotics. The diarrhoea could also prolong patients’ hospital stays and further exposing them to hospital-acquired infections.
“The problem is very real for patients who are unable to take amoxicillin-clavulanate because it gives them diarrhoea, even though it is an effective and affordable antibiotic for their infection. Knowing why may help us identify those at risk of antibiotic-associated diarrhoea, and devise treatment strategies in the future to minimise or avoid such adverse effects,” said lead researcher Dr Shirin Kalimuddin.
The study recruited 30 healthy volunteers, each receiving a three-day oral course of amoxicillin-clavulanate. Their stool samples were collected over four weeks and analysed using gene sequencing to look for changes in the gut microbiome.
Ruminococcaceae levels in the stools of study volunteers who developed diarrhoea were significantly lower when compared to those who did not, both before and during treatment with amoxicillin-clavulanate. This suggests that individuals may, depending on their gut composition, be predisposed to antibiotic-associated diarrhea. The team further devised a simple polymerase chain reaction (PCR) test based on levels of Faecalibacterium prausnitzii, a species within the Ruminococcaceae family, that could potentially be used in clinical settings to quickly determine an individual’s risk of developing diarrhea with amoxicillin-clavulanate treatment.
“People respond differently to medication. Understanding this response and the ability to predict those at risk will help guide the development of point-of-care diagnostics,” said lead researcher Professor Eric J. Alm.
“While a lot of attention has been paid to how DNA influences a person’s response to medication, the impact of the gut microbiome on the human drug response has not been widely researched. Our findings provide evidence that an individual’s gut microbial composition can influence the risk of developing antibiotics-associated diarrhoea. Tested against amoxicillin-clavulanate, the study provides a framework to identify other potential causes of antibiotic-associated diarrhoea in relation to other classes of antibiotics,” added Prof Alm.
The next step would be a clinical trial to determine whether certain Ruminococcaceae could be used as a probiotic to prevent diarrhoea in patients prescribed antibiotics.
Source: EurekAlert!
