Article in Japanese

Invasive infectious diseases caused by viridans streptococci

Hisamitsu TAMAKI, Masahiro OTSUKA, Masahiro ITO

Viridans streptococci are a part of normal microbial flora in the human oral cavity. They are considered as bacteria of low virulence; however, they also can invade natural barriers, infect a sterile site, and result in life-threatening diseases such as bacteremia, infective endocarditis, and brain abscess. In our hospital, 5 pediatric patients were treated from 2001 to 2012 for invasive infectious diseases caused by viridans streptococci. Streptococcus mitis and α-Streptococcus were isolated in 3 and 2 of the 5 patients respectively. In the final diagnosis of the 5 patients, brain abscess, bacteremia caused by S. mitis, infective endocarditis and graft-related infection caused by α-Streptococcus was found in 1 case, 2 cases, 1 case, and 1 case, respectively. Three of the 5 patients had underlying diseases such as ventricular septal defects in the patient with infective endocarditis; complete transposition of the great arteries repaired by a Blalock-Taussig shunt operation in the patient with graft-related infection; and spastic paralysis due to perinatal period disorder in one of the patients with bacteremia. Of the 2 healthy patients 1 case had a brain abscess following self-extraction of a milk tooth, and the other contracted bacteremia following chicken pox.

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Department of Pediatrics, Tokyo Metropolitan Bokuto Hospital

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Received	January 13, 2013
Accepted	February 27, 2013

25 (2)：137─143,2013