Methods: A systematic review to identify literature on risk factors for acquisition of ESBL-E was conducted using an English-language, human study Medline OVID search. Colonization was defined as the isolation of an ESBL-E organism from a non-sterile body site, whereas infection included associated signs and symptoms. High-risk (ICU admission, active malignancy, neutropenia, or organ transplant), nosocomial (isolates identified >72 hours post admission), and community infections (isolates identified < 72 hours post admission) were analyzed as separate populations.
Results: Previous antibiotic use was the most significant risk factor for colonization in high-risk (OR 5.38) and hospitalized patients (OR 9.8). Travel history, particularly to Southeast Asia (OR 8.63), India (OR 24.8), and Africa (OR 14.8), was a unique risk factor for colonization in the community. The greatest risk factor for ESBL-E infection across all patient groups was, again, antibiotic use (OR 3.22 – 5.49). This was attributed to the use of fluoroquinolones in hospitalized patients (OR 12.98) and cephalosporins in community settings (OR 13.61). Furthermore, the demographics of infected hospitalized patients primarily included elderly females (OR 2.30), whereas elderly males (OR 2.50) were more notable in the community. Finally, travel history was not only a risk factor for colonization but infection (OR 14.40 – 21.0) in the community.
Conclusion: Reported risk factors for ESBL colonization and infection vary greatly across literature, partly due to differences in study designs and populations included. Additional studies are required to delineate specific risk factors for early identification of ESBL, thereby guiding appropriate treatment and infection control practices.
A. V. Page, None