[Streptococcus gallolyticus (ex S. bovis) bacteremia and its relationship with colonic or hepatobiliary disease and endocarditis].

BACKGROUND: Bacteremia due to Streptococcus bovis (now S. gallolyticus) has been traditionally associated to colon or hepatobiliar disease and endocarditis but there is no information on this matter in Chile. AIMS: To describe clinical features of adult patients suffering bacteremia by S. bovis/S. gallolyticus, identify the source of the bacteremia and the frequency of endocarditis.
METHODS: Retrospective-descriptive study using laboratory records.
RESULTS: Between January 2003 and August 2014, 23 S. bovis/S. gallolyticus bacteremic events were identified among 22 patients. Mean age was 72.7 years (range 46-96). Co-morbidities were frequent (9.1 to 47.6%). The primary source of bacteremia was intestinal in 52.2%; hepatobiliar in 17.4% and in 34.8% it was not elucidated. Six patients had infective endocarditis (26.1%) and one patient had espondylodiscitis (4.3%). S. bovis represented 39.1% of isolates (all until 2008), S. gallolyticus subsp pasteurianus 39.1% and, S. gallolyticus subsp infantarius and S. gallolyticus subsp gallolyticus 8.7% each one, respectively. Association studies between the bacteremic source or endocarditis with specific S. gallolyticus subspecies were limited by the small number of isolates. Seven patients (30.4%) underwent surgical interventions. In-hospital mortality reached 21.7% (n=5).
CONCLUSIONS: Although infrequent, bacteremic events by S. gallolyticus/S. bovis have increased in-hospital mortality, require surgical intervention and affect older patients with co-morbidities. Near two-thirds suffer from colonic or hepatobiliary disease that act as the primary source of bacteremia. In addition, near one fourth is affected by infective endocarditis. Detection of S. gallolyticus/S. bovis in blood cultures prompts a thorough clinical evaluation in order to clarify the source of the bloodstream infection and the presence of complications.