Piperacillin-tazobactam use in ESBL <i>Escherichia coli</i> bacteremia: Should reporting be revised?
Bibliographic record
Abstract
Background: While certain extended-spectrum beta-lactamase (ESBL) producing Enterobacteriaceae may appear susceptible to piperacillin-tazobactam in the laboratory, controversy exists regarding its appropriateness to treat serious infections. The Clinical and Laboratory Standards Institute (CLSI) recommends that piperacillin-tazobactam susceptibility be reported as tested, and that ESBL screening is not required in Enterobacteriaceae. We evaluated a sequential group of patients with ESBL Escherichia coli bacteremia to determine the factors associated with piperacillin-tazobactam use despite this controversy. Methods: This was a retrospective observational study at the McGill University Health Center (832 beds) in Montréal, Canada, from April 2010 to June 2015, examining patients with positive blood cultures that grew E. coli. Pediatric, untreated, and duplicate cultures within 14 days were excluded. Antimicrobial susceptibility testing was determined in accordance with CLSI guidelines. Definitive therapy was defined as antibiotics given after susceptibility results became available. Results: There were 845 E. coli bacteremias in the data set, with a median patient age of 68 years (IQR 57–81.25) and a 30-day in-hospital mortality of 12.1%. Overall, there were 44 ceftriaxone-resistant, piperacillin-tazobactam-susceptible bloodstream infections (BSI), and 41 received definitive therapy. Of these, 14/41 (34.1%) received piperacillin-tazobactam and 30 had an infectious disease consult performed. Consult with infectious disease was associated with less use of piperacillin-tazobactam as definitive therapy (7/30 [23%] versus 7/11 [64%]; OR 0.17; 95% CI 0.03–0.96; p = 0.02). Conclusion: Piperacillin-tazobactam definitive therapy was used in approximately one-third of ceftriaxone-resistant E. coli bacteremias. Given a risk of increased mortality with the use of beta-lactam/beta-lactamase inhibitors for treating serious ESBL infections, microbiology laboratories should consider withholding piperacillin-tazobactam susceptibility results in such cases pending definitive evidence of clinical efficacy.
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 | 0.030 | 0.091 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.001 |
| Bibliometrics | 0.002 | 0.005 |
| Science and technology studies | 0.001 | 0.002 |
| Scholarly communication | 0.002 | 0.002 |
| Open science | 0.002 | 0.001 |
| Research integrity | 0.001 | 0.001 |
| Insufficient payload (model declined to judge) | 0.001 | 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".