Researchers at Florida State University’s Gut Biome Lab have conducted a groundbreaking study uncovering a possible connection between gut bacterial infections and the progression of Alzheimer’s disease.

The research found that the bacteria Klebsiella pneumoniae — a common bacteria notorious for causing hospital-acquired infections — can migrate from the gut into the bloodstream and eventually into the brain. This bacterial invasion may lead to increased inflammation in the brain and impair cognitive functions, mimicking symptoms seen in Alzheimer’s patients. The work was published in The Journal of Infectious Diseases.

The research suggests that when antibiotics disrupt the gut, it can lead to issues not just in the gut but also in the brain. Using a preclinical mouse model, researchers showed that antibiotic exposure depletes gut bacterial diversity and causes microbiome imbalance, which promotes the proliferation of K. pneumoniae by creating a favorable niche.

Implications for Hospital-Acquired Infections and Alzheimer’s Risk
When this happens, K. pneumoniae can move from the gut into the bloodstream by passing through the gut lining and eventually reach the brain, triggering neuroinflammation and neurocognitive impairment.