Streptobacillus moniliformis Endocarditis: An Unusual Case of Pulmonary Valve Erosion Resulting in Free Pulmonary Regurgitation and Aneurysm.

Endocarditis is a consideration in the differential diagnosis when masses are seen on echocardiography in a patient with congenital heart disease. We present a case of insidious development of endocarditis caused by Streptobacillus moniliformis in a seven-month-old baby after a rat bite, when the baby was three months of age.