Enterococcus faecalis is a Gram-positive bacterium responsible for a variety of life-threatening infections, including septicemia, endocarditis, peritonitis and urinary tract infections. Among these, urinary tract infections are among the most common infections caused by E. faecalis, accounting for approximately 110,000 cases yearly. E. faecalis infections are especially troublesome because they are often resistant to standard and last-resort antibiotics, and they serve as reservoirs of antibiotic resistance for other pathogens.
Very little is known about the factors used by E. faecalis to cause disease in the urinary tract or the response of the host to the presence of this bacterium. Research on E. faecalis in the Hultgren lab is focused on determining factors on both the host and pathogen side involved in causing disease in the urinary tract. To this end, a mouse kidney model of infection has been developed to study the steps in the pathogenesis of E. faecalis. This model has demonstrated that E. faecalis strains can cause a reproducible infection in the kidney but not in the bladder. Further studies will be directed at determining the factors involved in the apparent tropism of E. faecalis for the kidneys, and the host determinants that can prevent infection.