Infective Endocarditis in Neonates

We studied retrospectively the predisposing factors and signs of infective endocarditis (IE) in neonates and infants younger than 3 months of age, and we suggest diagnostic criteria. The charts of 16 infants less than 3 months of age, diagnosed with IE during a 5-year period, were reviewed for possible maternal and infant risk factors and for pathognomonic clinical and laboratory features. No apparent maternal risk factors were noted. Infant risk factors were congenital heart disease (4), patent ductus arteriosus (PDA) (5), and the use of central venous catheters (14). The main clinical findings were cardiac murmurs (12), petechiae (2), skin abscesses (7), arthritis (2), hepatomegaly (9), and splenomegaly (2). Echocardiography revealed a mass or vegetation in nine patients. Of the 27 microorganisms isolated from blood, the most common were staphylococci (15) and Candida sp. (6). Urine cultures were positive in six patients and cerebrospinal fluid cultures were positive in one. Other laboratory findings were not of diagnostic value. We conclude that the main risk factors for neonatal IE are central venous catheters and congenital heart disease, including PDA. The main causative microorganisms are staphylococci and Candida sp. The main investigations of diagnostic value are blood and urine cultures and echocardiography. We propose the diagnostic categories of definite, probable, and possible cases of neonatal IE, based primarily on clinical, blood culture, and echocardiographic data.