Rate of bacterial positivity following antibiotic initiation: a systematic review and meta-analysis
Abstract
Background: Bacterial culture remains a critical tool for pathogen identification and antimicrobial susceptibility testing. However, its diagnostic accuracy is often compromised by prior antibiotic administration, which can reduce the recovery of viable organisms and lead to false-negative results. Given the variability and limitations in the existing studies, a systematic review is needed to better understand the influence of antibiotics on culture yield.
Methods: We conducted an electronic search in PubMed, Embase, Scopus and Web of Science from their inception through March 2025. The Newcastle-Ottawa Scale was used to assess the methodological quality of the included articles. Random effects models were used to estimate the proportions and 95% Confidence Intervals (CIs). The protocol for this review was registered in PROSPERO: CRD42025648397.
Results: Of the 1226 articles obtained from the search, 11 were eligible. The eligible articles comprised 67,330 samples with culture results after antibiotic administration. The pooled proportion for bacterial growth was 37% (95% CI 20-56%) and 18% (95% CI 10-29%) before and after antibiotic administration, respectively. Significant heterogeneity (I2 = 99.8%, p-value < 0.001) was observed across the included studies.
Conclusion: Bacterial growth decreased by more than half following antibiotic administration, indicating a strong suppressive effect. This highlights the importance of considering the timing of sample collection in…
How strong is the evidence?
Evidence Hub reads this as a meta-analysis, done in people. Its evidence level is 1 of 5 (Highest · pooled evidence). Pooled evidence from several studies sits at the top of the evidence pyramid.
Read the paper
Related studies
- Horizontal gene transfer in the human gastrointestinal tract: potential spread of antibiotic resistance genes
- Mutation supply and relative fitness shape the genotypes of ciprofloxacin-resistant Escherichia coli
- Genomic Survey of E. coli From the Bladders of Women With and Without Lower Urinary Tract Symptoms
- Characterization of cefotaxime-resistant urinary Escherichia coli from primary care in South-West England 2017–18
- Fitness cost constrains the spectrum of marR mutations in ciprofloxacin-resistant Escherichia coli
- Emerging evidence-based innovative approaches to control catheter-associated urinary tract infection: a review
Go deeper in Evidence Hub
Evidence Hub adds a study data sheet (design, sample size, evidence level, key numbers), an AI summary and a chat grounded in the paper's text.