Gastrointestinal (GI) infections are extremely common in the US, and the culprit is usually a bacteria called Campylobacter. Typically, people can become ill with Campylobacter infection by eating undercooked poultry, meat, or eggs. They could also get the GI infection through cross contamination, such as using the same cutting board or utensils for raw poultry or meat and vegetables without washing. People can be infected by drinking raw (unpasteurized) milk.
The most common symptom of the GI-infection is diarrhea. While most symptoms resolve after treatment, they worsen for some individuals. This, in turn, leads to a poorly understood condition known as post-infection irritable bowel syndrome (PI-IBS). Essentially, their IBS was the result of the GI infection.
How this happens is still not fully known, but it is common enough to cause GI researchers to study the problem. Today, about 1 in 10 individuals develops PI-IBS after an episode of infectious gastroenteritis. The majority of cases are seen in the summer months and occur as single cases.
PI-IBS likely results from a complex interaction between the host — the human — and the pathogen — the bacteria — that led to changes in the intestinal function.
According to a meta-analysis study published in Gastroenterology several years back,
those most likely at risk are young women who experienced gastroenteritis and suffered from diarrhea that lasted more than seven days. Having bloody stools, abdominal cramps, and hospitalization because of the gastroenteritis are also strong indicators these individuals may eventually develop PI-IBS.
Psychological factors, such as anxiety, depression, neuroticism, and somatization (when psychological concerns turn to physical symptoms) during or preceding gastroenteritis also are associated with PI-IBS. Interestingly, fever protects against the development of PI-IBS, which means that the body’s response to the illness — a fever — may provide some protection.
These are several studies underway to study PI-IBS. Some suggest that GI infections caused by the Campylobacter bacteria changes in the microbiota and intestinal barrier function. However, researchers still need to study how this could lead to changes in the nerves and muscles in the gut.
Hopefully, we’ll someday have a clearer picture of this poorly understood condition. Until then, doctors need to be aware of the potential consequences of gastroenteritis so patients can be properly counseled and treated.