U. of Virginia researchers study how 'opportunistic pathogens' are tied to infections

A potentially deadly infection has a dangerous ally lurking in the human body, and researchers at the University of Virginia's (UVA) School of Medicine, along with collaborators from other institutions, have uncovered how certain microorganisms found in the gut can worsen potentially deadly C. difficile (C. diff) infections. 

The new findings could help medical professionals identify patients at risk for severe illness and pave the way for new treatments. C. difficile is a bacterium that is responsible for more than 350,000 infections in Americans annually, with elderly individuals and those on long-term antibiotics being particularly susceptible. 

These infections are characterized by symptoms such as diarrhea, fever, and nausea, and patients who survive are prone to suffer from re-infections, with one in six individuals developing another case within eight weeks, according to the Centers for Disease Control and Prevention. 

The UVA researchers found that enterococci, a group of antibiotic-resistant "opportunistic pathogens" found in the gut, can make C. diff infections more potent and dangerous. Enterococci are bacteria that can cause dangerous infections, such as meningitis, urinary tract infections, and gastrointestinal diseases. 

The team collected stool samples from patients with C. difficile infections at several medical institutions and used lab tests and advanced computer modeling to better understand how C. diff interacts with other microorganisms in the gut. 

They discovered that enterococci produce amino acids, including leucine and ornithine, which make C. difficile a more potent threat to patients whose gut compositions have been disrupted by antibiotics. 

The researchers, led by Jason Papin, a PhD from UVA's Department of Biomedical Engineering, developed powerful computer models that helped the team predict the complex changes in the gut. Their work showed that enterococci can dramatically reshape the "metabolome" in the gut and ultimately reprogram C. difficile, enhancing its disease-causing behaviors. 

The researchers hope that by better understanding how C. diff interacts with enterococci and other microorganisms in the gut, doctors will be better positioned to battle this common and serious infection. 

The findings have been published in the prestigious scientific journal Nature, and the research was supported by various grants from multiple sources, including from the National Institutes of Health. 

Papin and his team say that the study's findings show the power of computational models and data science in driving biological discovery. They believe that there are innumerable opportunities to use data science and computer modeling to drive biological discovery, and they are excited about the possibilities that lie ahead. 

The research team consisted of numerous individuals from different institutions.