IBS may persist in patients for years after bout of gastroenteritis

Aggressive and pro-inflammatory bacteria, such as Proteobacteria and Enterobacteriaceae, and the virus responsible for Covid-19 infection, SARS-CoV-2, are possible culprits, their findings suggest.

“Physicians should pay heed if their patients present with a recent episode of infectious gastroenteritis”

Study authors

IBS – characterised by abdominal pain, bloating, and altered bowel habit – and recurrent indigestion of unknown cause (functional dyspepsia), are disorders of the gut-brain axis.

Although common worldwide, their causes remain poorly understood, noted the researchers from the Catholic University of the Sacred Heart, Rome, in the journal Gut.

However, a sudden bout of gastroenteritis, usually brought on by a viral infection or food poisoning, is thought to be one of the possible triggers, highlighted the researchers.

They trawled databases, looking for published studies on the development of IBS or functional dyspepsia after a bout of gastroenteritis in people monitored for at least three months afterwards.

From 75 eligible studies, 45, involving a total of 2,1870 people mostly from Europe and North America, were suitable for a pooled data analysis. Sixteen were of high quality and the rest fair.

The prevalence of IBS after a bout of gastroenteritis was 14.5%. This was based on 46 studies involving 14,446 people.

Meanwhile, the prevalence of functional dyspepsia was nearly 13%, based on 13 studies involving 5,636 people.

Compared with those who had not had gastroenteritis, those who had were more than four times as likely to develop IBS and three times as likely to develop functional dyspepsia afterwards.

The pooled data analysis for IBS indicated that symptoms had persisted for between six and 11 months in 50% of people in five studies, and for one to four years in 52% of people in three studies.

In addition, symptoms lasted for more than five years in 40% of people in four studies.

The pooled data analysis pointed to certain risk factors for developing IBS after a bout of gastroenteritis, according to the researchers.

The most influential factor was a history of anxiety, which was associated with a three-fold heightened risk of IBS.

Diarrhoea lasting more than three weeks was associated with more than double the risk, while hospital admission and being female were associated with 65% and 59%, respectively, higher risk.

Analysis of the infectious agents involved showed that viruses were implicated in nearly 11% of cases, bacteria in just over 18%, and parasites in 30%.

The highest prevalence of IBS after gastroenteritis was associated with Campylobacter infection, followed by Proteobacteria, Enterobacteriaceae and those infected with SARS-CoV-2 or parasites.

The prevalence of functional dyspepsia after gastroenteritis was nearly 14% for bacterial infections and 10% for SARS-CoV-2 infection, with Enterobacteriaceae species the most common source.

The study authors said: “The pathophysiology of [disorders of gut-brain interaction] is poorly understood.

“These disorders are traditionally perceived by healthcare professionals as being mostly psychological and less ‘valid’ diseases, with a potential risk of underestimating patients’ expectations and complaints,” they said.

“Generally, as acute gastroenteritis is a common disorder worldwide, our findings may be relevant for public health, and physicians should pay heed if their patients present with a recent episode of infectious gastroenteritis,” they added.