Streptococcal endocarditis: a meta-analysis of species dependant risk
Bibliographic record
Abstract
Background Streptococcal infective endocarditis (IE) is a devastating disease. In international guidance, the risk of IE from streptococci is considered the same regardless of species (excluding Streptococcus pyogenes and Streptococcus pneumoniae ). However, the idea of homogenous risk has been recently questioned. We aimed to evaluate the risk of IE across streptococcal species through meta-analysis of other published works and our own local data. Methods We first conducted a scoping review for publications that reported cases of streptococcal bacteraemia differentiated by species and estimated the risk of IE between 1994 and October 2024. Then we supplemented this data with our own laboratory data from four large hospitals. We meta-analysed the risk of IE. Two sensitivity analyses were performed to deal with one manuscript which excluded cultures considered as contaminants: first, by excluding that publication, and second by adjusting for blood culture contamination using our local estimated contamination rates. Findings Four studies met inclusion criteria comprising a total of 14,183 isolates with 1028 endocarditis cases (7.25% absolute risk of IE). The highest risk species were: Streptococcus mutans : 47% (95% CI 38–56%), Streptococcus cristatus : 41% (95% CI 21–62%), Streptococcus gordonii : 37% (95% CI 30–44%), Streptococcus sanguinis 33% (95% CI 28–39%), and Streptococcus gallolyticus : 31% (95% CI 27–36%). Combined, these species accounted for only 8.4% of bacteraemias but 38.6% of IE. The most common IE pathogen overall was Streptococcus mitis/oralis (23.6% of IE, 8% of bacteraemias) but these infections themselves only carried an IE risk of 12% (95% CI 11–13%). There was strong evidence of heterogeneity detected in S. mitis/oralis (I 2 87%; Cochran's Q: 30 p: <0.001) and S. gallolyticus (I 2 90%; Q: 29 p: <0.001). Interpretation The ‘small five' streptococci: S. mutans, S. cristatus, S. gordonii, S. gallolyticus, and S. sanguinis account for only 8% of all streptococcal bloodstream infections but nearly 40% of all streptococcal IE with a risk of IE in individual infections as high as ∼50%. The risk of S. mitis/oralis appears heterogeneous, may depend on species or subspecies, and requires further study. Funding FH was funded by the NIHR Clinical Lectureship Scheme. TL has salary support from Fonds de Recherche Québec - Santé. PW is funded by a Medical Research Council grant MR/T005408/1.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.021 | 0.039 |
| Meta-epidemiology (narrow) | 0.003 | 0.002 |
| Meta-epidemiology (broad) | 0.011 | 0.062 |
| Bibliometrics | 0.004 | 0.005 |
| Science and technology studies | 0.001 | 0.001 |
| Scholarly communication | 0.004 | 0.002 |
| Open science | 0.002 | 0.002 |
| Research integrity | 0.003 | 0.003 |
| Insufficient payload (model declined to judge) | 0.004 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".