Abstract
Ruminococcus gnavus (R. gnavus), which constitutes a part of the human intestinal flora, has been isolated in cases of septic arthritis and bacteremia with intestinal lesions. We report a case of bacteremia with R. gnavus in a very elderly man who presented with prolonged fever, but in whom the bacteremia was not associated with septic arthritis or intestinal lesion.
A 90-year-old man exhibited fever of approximately 38°C for 2 months. Two sets of blood culture samples were obtained. R. gnavus was detected in one of the anaerobic culture samples. Contrast computed tomography, positron emission tomography, and lower gastrointestinal-tract endoscopy did not demonstrate septic arthritis or intestinal lesions. He was treated for 16 days with ampicillin (4,000 mg) and 7 days with metronidazole (1,500 mg) intravenously, which resulted in improvement of his symptoms and negative blood culture. This is the first case of R. gnavus bacteremia without septic arthritis or intestinal lesions in a very elderly patient. With the global increase in the aging population, such cases are likely to become more frequent.
Our experience suggests that it is important to perform blood cultures in order to clarify the cause of fever in the elderly. As there are only a few case reports of R. gnavus infection, this report presents a novel clinical feature of R. gnavus infection.
