Which bacteria is most commonly associated with infective endocarditis?

The bacteria most commonly associated with infective endocarditis are indeed Strep viridans, Staph aureus, and Enterococcus. These organisms are pivotal in this condition for several reasons.

Streptococcus viridans is a group of alpha-hemolytic streptococci that are part of the normal flora of the oral cavity. They become significant in infective endocarditis, particularly after dental procedures or poor oral hygiene, as they can enter the bloodstream and adhere to previously damaged heart valves.

Staphylococcus aureus is a more aggressive pathogen associated with infective endocarditis, particularly in individuals with more acute presentations or underlying conditions such as intravenous drug use. It has a tendency to cause more rapid and severe infections.

Enterococcus is another important organism that can cause endocarditis, especially in older adults and those with urinary tract or gastrointestinal infections. Its ability to survive in a wide range of environments and its inherent antibiotic resistance can make infections difficult to treat.

In contrast, other bacteria listed, such as Escherichia coli, Staphylococcus epidermidis, and Neisseria gonorrhoeae, are less commonly associated with infective endocarditis. While they can cause other types of infections, they do