Global Bacterial Spectrum, Diagnostic Culture Yield, and Microbiology-Related Mortality Risk in Infective Native Aortic Aneurysm: A Systematic Review and Meta-Analysis.

BACKGROUND

Infective native aortic aneurysm (INAA) is a rare, fatal vascular infection, but its microbiology has been less synthesized than repair strategy. We assessed bacterial spectrum, culture yield, concurrent infectious foci, and microbiology-related mortality risk.

METHODS

We systematically reviewed studies published to November 2024. The primary meta-analysis included 79 studies with 3,835 patients; 232 culture-confirmed case reports or small series (258 patients) were used only for descriptive pathogen mapping. Proportions were pooled with random-effects logit models, and hazard ratios (HRs) on the log-HR scale.

RESULTS

The descriptive microbiology dataset included 4,093 patients, 2,609 with confirmed bacterial etiology. Salmonella was the leading genus globally (30.6%), followed by Staphylococcus (25.6%) and Streptococcus (11.8%). Staphylococcus predominated in developed countries (30.8%), whereas Salmonella dominated developing countries (59.0%) and China (60.6%). Any microbiological detection was achieved in 64.9% (95% CI, 60.1-69.4%; I2 = 82.0%). Blood culture, aortic tissue, preoperative, and intraoperative sampling positivity were 52.6%, 57.2%, 51.4%, and 61.4%, respectively. The most frequent concurrent foci were gastroenteritis (12.0%), spondylodiscitis (11.7%), urinary tract infection (8.6%), endocarditis (7.0%), and pneumonia (6.8%). Non-Salmonella-positive culture was associated with higher mortality (HR, 1.66; 95% CI, 1.14-2.42); negative culture, Salmonella-positive culture, and positive blood culture were not statistically significant.

CONCLUSION

INAA microbiology is geographically polarized, and culture yield remains incomplete across sampling strategies. These findings support region-aware empirical therapy, routine blood and tissue sampling with antibiotic-timing documentation, and pathogen-stratified registries and guidelines.