Abstract
Listeria monocytogenes is a prevalent gram-positive intracellular zoonotic pathogen that is frequently associated with foodborne illnesses and opportunistic infections. This bacterium is responsible for causing various clinical manifestations, including bacteremia, meningitis, and encephalitis, and is primarily transmitted through contaminated food consumption. This study presents two cases of severe endocarditis in patients with heart valve disease caused by L. monocytogenes. Infection was confirmed by blood culture and pathogen culture of the valve pus. Early detection, clinical suspicion, and appropriate treatment are crucial for improving the prognosis of patients with listeriosis. The combination of ampicillin and aminoglycosides remains the most effective treatment for listeriosis.