Some significant risk factors are listed here:
Artificial heart valves
Intracardiac devices, such as implantable cardioverter-defibrillators
Unrepaired cyanotic congenital heart defects
History of infective endocarditis
Neoplastic disease
Chronic rheumatic heart disease, which is an autoimmune response to repeated Streptococcus pyogenes infection (mostly in the developing world)
Age-related degenerative valvular lesions
Congenital heart valve abnormalities
Hemodialysis, a medical procedure that filters the blood of individuals with kidney failure
Poor oral hygiene
Coexisting conditions, especially ones that suppress immunity. Diabetes mellitus, alcohol use disorder, chronic liver disease, HIV/AIDS, and intravenous drug use all fall in this categoryMore detailed descriptions of these and other risk factors are provided below. Other conditions that result in large numbers of bacteria entering into the bloodstream include colorectal cancer (mostly Streptococcus bovis), serious urinary tract infections (mostly enterococci), and drug injection (Staphylococcus aureus). With a large number of bacteria, even a normal heart valve may become infected. A more virulent organism (such as Staphylococcus aureus) can cause infective endocarditis by infecting even a normal heart valve.People who inject drugs tend to get their right-sided heart valves infected because the veins that are injected drain into the right side of the heart. In rheumatic heart disease, infection occurs on the aortic and the mitral valves on the left side of the heart.Other factors that increase the risk of developing infective endocarditis are low levels of white blood cells, immunodeficiency or immunosuppression, malignancy, diabetes mellitus, and excessive alcohol use.
Cutibacterium spp., which are normal skin flora, have been responsible for infective endocarditis, preferably in patients with prosthetic heart valves, in rare cases leading to death.Tropheryma whipplei has caused endocarditis without gastrointestinal involvement. Citrobacter koseri was found in an immunocompetent adult. Neisseria bacilliformis was found in a person with a bicuspid aortic valve. Fungal
Fungal endocarditis (FE) is often fatal and one of the most serious forms of infective endocarditis. The types of fungi most seen associated with this disease are:
Candida albicans is found as a spherical or oval budding yeast. It is associated with endocarditis in people who inject drugs, patients with prosthetic valves, and immunocompromised patients. It forms biofilms around thick-walled resting structures like prosthetic heart valves and additionally colonizes and penetrates endothelial walls. C. albicans is responsible for 24-46% of all the cases of FE, and its mortality rate is 46.6–50%.Other fungi demonstrated to cause endocarditis are Histoplasma capsulatum and Aspergillus. Aspergillus contributes to roughly 25% of FE cases. Endocarditis with Tricosporon asahii has also been reported in a case report. Risk factors
Risk factors for infective endocarditis are based on the premise that in a healthy individual, bacteremia (bacteria entering the bloodstream) is cleared quickly with no adverse consequences. However, if a heart valve is damaged, the bacteria can attach themselves to the valve, resulting in infective endocarditis. Additionally, in individuals with weakened immune systems, the concentration of bacteria in the blood can reach levels high enough to increase the probability that some will attach to the valve.