Discussion
infection, ESBL-E carriage
INFECTION, SECONDARY
In this secondary analysis of a large clinical trial in four European healthcare institutions with endemic ESBL-E, despite using an extensive screening program exceeding routine hospital practice, surveillance cultures obtained on the study wards identified only little more than one-third of ESBL-E carriers in time for subsequent contact isolation. Moreover, 41% of ESBL-E carriers were discharged before any pathogen-directed preventive measures could be started.Debate continues regarding the value of surveillance screening for ESBL-E.Screening as part of a vertical strategy to prevent the spread of ESBL-E should only be undertaken if identified ESBL-E carriers are treated differently from non–ESBL-E carriers. Otherwise, there would be no added value over horizontal strategies.Several factors may explain the limitations of approaches involving screening for ESBL-E carriage. First, in our cohort, the median duration between collecting the positive sample and initiation of contact isolation was 4 days among patients without previous history of ESBL-E carriage. Laboratory procedures may be faster in other settings, or may have accelerated since,The analytical laboratory processes could be considerably shortened with the use of rapid molecular techniques because total hands-on time in the laboratory from the arrival of the sample to the test result rarely exceeds 1 hour.Second, screening approaches on admission in real-life scenarios are often hindered by time delays between admission and collecting the sample, particularly in non-ICU wards, because patients are often mobile and may thus not be present during screening rounds. Moreover, discharge management and completion of nonessential examinations may not always align perfectly. Our results show that patients without screening had a shorter LOS compared with screened patients. This difference in length of stay was even more striking in patients with and without contact isolation, reflecting the combined effect of incomplete adherence to screening requirements, a relatively long turnaround time and subsequent contact isolation in patients with a short LOS.Third, routine hospital-based MDRO surveillance strategies only rarely comprises screening cultures obtained after admission to the wards. ESBL-E acquisition within the hospital, for example, through patient-to-patient transmission or through selection processes by antimicrobial chemotherapyAlmost 30% of ESBL-E carriers had a history of ESBL-E carriage; among them, almost 90% were placed in contact isolation from their first day of admission. Therefore, the benefit of screening programs should be considered not only for the patient’s current hospital stay during which the culture was obtained but also for potential future readmissions. Following this line of argument, in terms of subsequent hospital admissions, systematic discharge screening would be even more relevant.Fourth, even a universal screening protocol focusing only on admissions generates massive workload for healthcare and laboratory staff as well as substantial expenditures for the hospital system, whereas its health–economic benefit has not been evaluated in the contemporary epidemiological context.The dilemma between increasing burdens on patients and institutions in a rather imperfect attempt to prevent further spread or accepting the ineffectiveness of the screening program is yet to be solved.This study had several limitations. Adherence to the screening protocol was not 100%, but the screening extended well beyond what could be expected from real-life scenarios. We may have underestimated the number of ESBL-E days because the screening protocol allowed for admission screening within the first 3 days of admission (day of admission plus the following 2 days). We were unable to provide more granularity on the specific cause of the time delay because we did not collect data on the arrival time of the specimen in the laboratory or the timestamp of the laboratory result. In addition, the aforementioned day-wise instead of hourly data collection may have overestimated turnaround time. We screened surveillance cultures from rectal swabs without broth enrichment and extended incubation to enhance test sensitivity because turnaround time for reporting positive results would have increased.Despite maximum efforts in terms of surveillance screening, initiation of contact isolation was not possible for a large proportion of ESBL-E carriers before discharge. Although the screening protocol far exceeded routine practice, and although the samples were processed by local laboratories from 4 European university hospitals, almost one-third of all ESBL-E days were nonisolated, and >40% of ESBL carriers were not placed in contact isolation precautions while on the ward. As long as limitations in routine ESBL-E detection as well as high numbers of ESBL-E carriers impede timely, exhaustive, and correct implementation of targeted infection control approaches, efforts to contain the spread of ESBL-E within the hospital should focus on horizontal approaches such as standard precautions and antibiotic stewardship.