Streptococcus bovis bacteraemia revisited: Clinical and microbiological correlates in a contemporary series of 59 patients
Introduction
Streptococcus bovis, a non-enterococcal group D streptococcus, is a commensal inhabitant of the human digestive tract that may be isolated in up to 16% of faecal samples from normal individuals.1, 2 Since the first case report in 1951 by McCoy and Mason3 and the pivotal control-case study by Klein et al,4 the association between S. bovis bacteraemia and gastrointestinal diseases, specifically colorectal carcinoma, has been extensively established in the literature.5, 6 Based on such evidence, some authors have recommended a complete colonic evaluation in all patients with documentation of S. bovis bacteraemia, although the reliability and cost-effectiveness of this strategy remain to be assessed.7, 8 More recent studies have stressed the frequent association between the infection caused by this agent and the presence of chronic liver and biliary tract disorders as predisposing conditions.9, 10, 11S. bovis is also responsible for approximately 6% of all cases of infective endocarditis (IE) worldwide, as recently reported by the International Collaboration on Endocarditis (ICE) group, with particular relevance in southern Europe.12 In addition, this prevalence rises up to 8.3% in individuals aged 65 years or older.13 As demonstrated by Tripodi et al14 in a large series from Italy, S. bovis IE is frequently correlated with advanced liver disease.
Traditionally, S. bovis strains have been physiologically divided into biotypes I (also called “classic”) and II or “variant” (further separated into II/1 and II/2 strains), according to the ability of the former to hydrolyse starch and ferment mannitol.15 It has been suggested that bacteraemia caused by S. bovis biotype I has a much stronger association with the presence of an underlying gastrointestinal cancer or the occurrence of IE, as opposed to infection caused by biotype II.6 To date the clinical correlates of S. bovis biotype II have been poorly studied. On the other hand, some extensive taxonomic changes have been proposed in the S. bovis/S. equinus group in the last few years.16 According to current terminology, based on DNA–DNA reassociation and whole-cell protein analysis, strains formerly termed S. bovis (biotype I) and S. bovis variant (biotype II/2) are now denominated S. gallolyticus and S. pasteurianus, respectively, while the former S. bovis variant (biotype II/1) is now named S. infantarius.17 Nevertheless, most clinicians still remain unfamiliar with biotypes or newer S. bovis species, and clinical correlates are uncommon.18
Most of the studies regarding the clinical and microbiological correlates of patients with S. bovis bacteraemia were performed several years ago;7, 19, 20 they included relatively small samples7, 9, 14, 15 or suffered from considerable heterogeneity in the diagnostic and methodological criteria.6 Thus, this study was aimed to review our experience with S. bovis bacteraemia in a large, contemporary series of patients from a single tertiary-care centre, paying special attention to demographic and clinical associations in relation to the different biotypes and microbiological findings.
Section snippets
Patient selection and definitions
We performed a retrospective analysis of all blood cultures positive for S. bovis at our institution between 1 January 1997 and 30 November 2008, identified by a search of computerised bacteriology records of the Department of Microbiology. The University Hospital 12 de Octubre is a 1300-bed tertiary-care centre in central Spain, with a reference population of over 750,000 inhabitants in 2003. During the study period a total of 68 consecutive episodes of S. bovis bacteraemia were documented in
Results
A total of 68 episodes of S. bovis bacteraemia were documented in 9 paediatric and 59 adult patients (aged ≥18 years) during the study period. The paediatric group included 8 females and one male, with a mean age of 2.2 ± 0.03 months; eight were neonates (aged ≤1 month). A presumed source of infection was identified in 3 of them (bronchopneumonia in 2 cases, and meningitis in one case). One infant was a preterm with hyaline membrane disease and pulmonary hypoplasia. None of these paediatric
Discussion
The clinical relationship between S. bovis bacteraemia and underlying gastrointestinal diseases has been well-known for years.3, 4, 5 However, to date, there has been no satisfactory explanation regarding the pathophysiologic mechanism for this association. Klein et al4 reported more than three decades ago that the prevalence of S. bovis in faecal cultures was significantly increased in patients with colorectal carcinoma compared with that of control subjects, although some other studies have
Financial support
There was no grant support for this work.
Potential conflicts of interest
All authors: none to declare.
References (40)
- et al.
Impact of inappropriate empirical therapy for sepsis due to health care-associated methicillin-resistant Staphylococcus aureus
J Infect
(2009) - et al.
Spontaneous bacterial peritonitis caused by Streptococcus bovis: case series and review of the literature
Am J Gastroenterol
(2002) - et al.
Streptococcus bovis bacteraemia and its association with alimentary-tract neoplasm
Lancet
(1987) - et al.
Streptococcus bovis bacteraemia: identification within organism complex and association with endocarditis and colonic malignancy
Pathology
(2009) - et al.
Molecular epidemiology of Streptococcus bovis causing endocarditis and bacteraemia in Italian patients
Clin Microbiol Infect
(2005) Recognition of group D streptococcal species of human origin by biochemical and physiological tests
Appl Microbiol
(1972)Carriage of group D streptococci in the human bowel
J Clin Pathol
(1978)- et al.
Enterococcal endocarditis associated with carcinoma of the sigmoid: report of a case
J Med Assoc State Ala
(1951) - et al.
Association of Streptococcus bovis with carcinoma of the colon
N Engl J Med
(1977) - et al.
Infectious agents and colorectal cancer: a review of Helicobacter pylori, Streptococcus bovis, JC virus and human papillomavirus
Cancer Epidemiol Biomarkers Prev
(2008)
Streptococcus bovis endocarditis; a silent sign for colonic tumour
Colorectal Dis
Streptococcus bovis bacteraemia requires rigorous exclusion of colonic neoplasia and endocarditis
Q J Med
Association of Streptococcus bovis bacteraemia with colonic neoplasia and extracolonic malignancy
Arch Surg
Prevalence of liver disease in patients with Streptococcus bovis bacteraemia
J Infect
Geographical difference of disease association in Streptococcus bovis bacteraemia
J Med Microbiol
The association of Streptococcus bovis bacteremia and gastrointestinal diseases: a retrospective analysis
Dig Dis Sci
Clinical presentation, etiology, and outcome of infective endocarditis in the 21st century: the International Collaboration on Endocarditis-Prospective Cohort Study
Arch Intern Med
Current features of infective endocarditis in elderly patients: results of the International Collaboration on Endocarditis Prospective Cohort Study
Arch Intern Med
Streptococcus bovis endocarditis and its association with chronic liver disease: an underestimated risk factor
Clin Infect Dis
Bacteremia with Streptococcus bovis and Streptococcus salivarius: clinical correlates of more accurate identification of isolates
J Clin Microbiol
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