Infective Endocarditis Due to Streptococcus gallolyticus subsp. pasteurianus with Pulmonary Vein Obstruction

Excerpt

To the Editor: Streptococcus gallolyticus subsp. pasteurianus is known to cause bacteremia or infectious endocarditis (IE) in adult patients with digestive tract malignancies [1]. In contrast, a limited number of cases have been reported in children, and these cases involved meningitis or sepsis [2, 3]. Here, we report the first case of possible IE in an infant. A 5-mo-old boy presented with tachypnea and marked cyanosis. His medical history included total anomalous pulmonary venous return (TAPVR) and pulmonary vein obstruction (PVO). On admission, he had fever, tachycardia, and tachypnea. Initial tests were performed on blood and urine samples. Twelve hours after admission, a blood culture test revealed gram-positive cocci. We performed a second blood culture test suspecting IE, while deciding to begin treatment with vancomycin. Ten hours after incubation, the second blood culture test result also showed gram-positive cocci. The following day, the bacterial strain was finally revealed to be S. gallolyticus subsp. pasteurianus, which was confirmed later by multilocus sequence typing. The two positive blood cultures from blood samples drawn >12 h apart, a medical history of congenital heart disease (CHD), and a temperature of >38 °C fulfilled one major, and two minor clinical criteria of IE, based on the Modified Duke Criteria [4]. Therefore, the patient was diagnosed as having possible IE. Considering the minimum inhibitory concentrations of penicillin G and gentamicin, we chose to administer a 2-wk treatment regimen. The patient’s condition gradually improved, and 19 d after admission, he was finally discharged. After the introduction of the universal pneumococcal conjugate vaccine, bacteremia became rare. Fewer blood cultures are recommended from young febrile children because of the low frequency of bacteremia in those children [5]. However, for patients with CHD presenting with fever, collecting a blood culture sample may be important to determine the appropriate treatment. No standard treatment has been established for S. gallolyticus subsp. pasteurianus. These bacteria are generally sensitive to penicillin. However, several isolates have been reported to have intermediate resistance to penicillin [2]. Thus, it is important to collect a blood culture sample to identify the causative microorganism and choose appropriate antibiotics. …