Association of Race or Ethnicity With Extended-Spectrum Beta-Lactamase Production in Escherichia Coli: A Case Control Study.

Background: There are limited and conflicting data regarding the impact of race or ethnicity on the rate of gram-negative antimicrobial resistance. This study was performed to determine whether there is a difference in extended-spectrum beta-lactamase (ESBL) Escherichia coli infection or colonization in minoritized patients when compared to White patients from a diverse US Midwestern city.

Methods: A case control study was performed, with controls with non-ESBL E. coli matched 1:1 to patients with ESBL-producing E coli based on age, sex, and ZIP code. A variety of other evidence-based factors for ESBL Enterobacterales infection and colonization were collected via chart review. Multivariate conditional logistic regression assessed the odds of minoritized patients as compared to White patients, while controlling for other common risk factors for ESBL Enterobacterales.

Results: A total of 364 matched pairs were included in the analysis. Females were the majority of the sample (91%), with median age of 65 years. The majority of the sample identified as White (73%), followed by Hispanic (14%) and Black (10%). Urine cultures made up the majority of the cultures in the sample (97%), and this was similar between ESBL and non-ESBL groups. While controlling for these risk factors for ESBL E coli, minoritized patients had a statistically significant greater odds of ESBL-producing E coli (odds ratio, 2.53; 95% confidence interval, 1.68-3.82).

Conclusions: In our sample, which is demographically similar to the United States, minoritized patients had higher odds of ESBL-producing E coli. Further research on the drivers for this disparity is needed.