Cefotetan Therapy for Escherichia Coli Infections

Inclusion Criteria (clinical cohort): * Identified within 48 hours of inpatient antibiotic administration for acute illness. * Patient or legally authorized representative are able to provide informed consent for participation in the study. * Monomicrobial E. coli bacteremia with a genitourinary source. * Isolate susceptible to both ertapenem and cefotetan (ESBL infections) or ceftriaxone and cefotetan (non-ESBL infections). Exclusion Criteria (clinical cohort): * Allergy to cefotetan. * History of cephalosporin-associated hemolytic anemia. * Allergy to ertapenem or meropenem (among patients with ESBL E. coli infections). * Allergy to ceftriaxone (among patients with non-ESBL E. coli infections). Includes allergy to antibiotics with a similar structure expected to confer cross reactivity to ceftriaxone (cefotaxime, cefpodoxime, ceftazidime). * Admission within 30 previous days. * Any bacteremia with the same organism in the previous 90 days. * Pregnant or breastfeeding. * Moderately to severely immunocompromised, including solid organ or stem cell transplant, hematologic malignancy, active chemotherapy. * Admission with neutropenic fever. * Severe illness, including shock and/or intensive care unit admission. * Inability to complete at least 72 hours of appropriate parenteral therapy, including at least 1 dose cefotetan for patients randomized to the treatment arm or at least 1 dose of appropriate parenteral therapy following randomization for patients assigned to the standard of care arm.