Background: Clinical pharmacists are a critical part of antibiotic stewardship. Stewardship often relies on relationships and persuasion, which may be affected by gender bias. Thus, we aimed to assess the association of sex with the acceptance of antibiotic stewardship recommendations. Methods: Between May and October 2019, medicine pharmacists at single hospital reviewed patients on antibiotics and–when a discharge was anticipated–led an antibiotic discussion (or “timeout”) prior to discharge. To explore differences in antibiotic timeout effectiveness by gender, we assessed the association of pharmacist sex with suggestion and acceptance of antibiotic changes using logistic regression controlling for patient characteristics. We also assessed whether hospitalist sex was associated with or moderated the effect of pharmacist sex on acceptance of timeout recommendations. Results: Between May 1, 2019, and October 31, 2019, pharmacists conducted 295 timeouts (patient characteristics in Fig. 1). Overall, 54% of timeouts were conducted by 12 female pharmacists and the remaining 46% were conducted by 8 male pharmacists. Overall, 82 (29%) of 295 timeouts resulted in a pharmacist recommending an antibiotic change, and male pharmacists were more likely to recommend a change: 52 (38%) of 137 versus 30 (19%) 158 (P Conclusions: In this discharge antibiotic intervention, timeouts conducted by women were less likely to result in an antibiotic change than those conducted by men. The difference in effectiveness resulted both from female pharmacists being less likely to recommend a change and from hospitalists being less likely to accept recommendations from a female pharmacist. These findings suggest that gender bias may play a role acceptance of antibiotic stewardship recommendations, which could affect antibiotic use, pharmacist job satisfaction, and patient outcomes.

Funding: None

Disclosures: None

We evaluated the impact of preliminary blood-culture antibiotic susceptibility testing on time to optimal antibiotic therapy in a cohort of 503 patients with monomicrobial bloodstream infections. The median time from blood-culture collection to optimal antibiotics was 17 hours earlier in the preliminary antibiotic susceptibility testing group.

Background: Antibiotics targeted against Clostridioides difficile bacteria are necessary, but insufficient, to achieve a durable clinical response because they have no effect on C. difficile spores that germinate within a disrupted microbiome. ECOSPOR-III evaluated SER-109, an investigational, biologically derived microbiome therapeutic of purified Firmicute spores for treatment of rCDI. Herein, we present the interim analysis in the ITT population at 8 and 12 weeks. Methods: Adults ≥18 years with rCDI (≥3 episodes in 12 months) were screened at 75 US and CAN sites. CDI was defined as ≥3 unformed stools per day for <48 hours with a positive C. difficile assay. After completion of 10–21 days of vancomycin or fidaxomicin, adults with symptom resolution were randomized 1:1 to SER-109 (4 capsules × 3 days) or matching placebo and stratified by age (≥ or <65 years) and antibiotic received. Primary objectives were safety and efficacy at 8 weeks. Primary efficacy endpoint was rCDI (recurrent toxin+ diarrhea requiring treatment); secondary endpoints included efficacy at 12 weeks after dosing. Results: Overall, 287 participants were screened and 182 were randomized (59.9% female; mean age, 65.5 years). The most common reason for screen failure was a negative C. difficile toxin assay. A significantly lower proportion of SER-109 participants had rCDI after dosing compared to placebo at week 8 (11.1% vs 41.3%, respectively; relative risk [RR], 0.27; 95% confidence interval [CI], 0.15–0.51; p-value <0.001). Efficacy rates were significantly higher with SER-109 vs placebo in both stratified age groups (Figure 1). SER-109 was well-tolerated with a safety profile similar to placebo. The most common treatment-emergent adverse events (TEAEs) were gastrointestinal and were mainly mild to moderate. No serious TEAEs, infections, deaths, or drug discontinuations were deemed related to study drug. Conclusions: SER-109, an oral live microbiome therapeutic, achieved high rates of sustained clinical response with a favorable safety profile. By enriching for Firmicute spores, SER-109 achieves high efficacy while mitigating risk of transmitting infectious agents, beyond donor screening alone. SER-109 represents a major paradigm shift in the clinical management of patients with recurrent CDI. Clinicaltrials.gov Identifier NCT03183128. These data were previously presented as a late breaker at American College of Gastroenterology 2020.

Funding: Seres Therapeutics

Disclosures: None

Figure 1.

Background: Sink drains can act as breeding grounds for multidrug-resistant (MDR) bacteria, leading to outbreaks. Drains provide a protected humid environment where nutrient-rich substances are available. Recent and growing installation of water and energy conservation devices have led to increased frequency of drain blockage due to biofilm accumulation. Ineffective drainage may lead to backflow and accumulation of water in the sink during use, increasing the risk of contaminated aerosols formation or direct contamination of surrounding material and equipment. Cleaning and disinfection procedures of sink drains need to be improved to prevent amplification and dispersion of MDR bacteria. The objective of this study was to investigate alternatives to reduce the biofilm and risk of contamination through aerosols. Methods: Sink drains from patient rooms were randomly selected in the neonatal intensive care unit of a 450-bed pediatric hospital. We tested 4 approaches: (1) new drain; (2) self-disinfecting heating-vibration drain; (3) chemical disinfection with 20 ppm chlorine for 30 minutes; and (4) thermal disinfection with > 90°C water for 30 minutes. A special device was used during disinfection to increase the disinfectant contact time with the biofilm. Treatments were conducted weekly, with prior sampling of drain water. Other drains were also sampled weekly, including a control drain with no intervention. Bacterial loads were evaluated using flow cytometry and heterotrophic plate counts. The drains were made of stainless steel, a heat-conductive material. Results: Preliminary results show that chlorine disinfection had a small impact (<1 log) on culturable bacteria at 48 hours after disinfection but not after a week or repeated weekly disinfection. Thermal disinfection using boiling water is promising, showing an important decrease of 4 log in culturable cells after 48 hours and a concentration still 100× lower 1 week after the disinfection. Repeated weekly thermal disinfection maintained lower culturable levels in the drain. No culturable cells were detected in water from the self-disinfecting drain 2 months after installation, whereas the new drain became fully colonized to concentrations similar to those of drains prior to interventions during the same period. Conclusions: Thermal disinfection of drains is a promising alternative to chlorine. This solution is interesting because it is nontoxic and easy to perform, requiring a small volume of hot water. The rapid recolonization of the new drain suggests that replacing contaminated drains is not a sustainable solution and would need to be paired with a thermal disinfection program to maintain low culturable cells.

Funding: No

Disclosures: None

Background: Admission laboratory screening for asymptomatic COVID-19 has been utilized to mitigate healthcare-associated SARS-CoV-2 transmission. A better understanding of the impact of such testing across a variety of patient populations is needed. Methods: Beginning April 2020, every patient admitted within an academic healthcare system underwent SARS-CoV-2 PCR testing upon admission. Between April 20, 2020 through June 14, 2021, results were analyzed in asymptomatic patients across 4 inpatient facilities: a tertiary-care adult hospital, a free-standing pediatric hospital, a community-based hospital, and a behavioral health hospital. Positivity rates and the number needed to test (NNT) to identify 1 asymptomatic infected patient were calculated overall, by hospital type, by patient vaccination status, and by CDC-defined levels of community transmission. Weekly community incidence rates of COVID-19 for the system’s metropolitan service area (8 central Tennessee counties) were obtained from Tennessee Department of Health records. Weekly COVID-19 incidence rates per 100,000 people were calculated using US Census Bureau data. Using a national survey of hospital epidemiologists, a clinically meaningful NNT was identified (ie, 1 positive patient per 100 patients tested). A crude admission testing cost (covering testing supplies, reagents, and lab personnel costs) was obtained from operational data ($50 per test) to assess testing utility. Results: In total, 51,187 tests were collected during the study period with a positivity rate of 1.8%. No periods of low transmission were observed (Table 1). During high transmission periods, the NNT met the clinically relevant threshold in all populations. In addition, the NNT approached or met the 1:100 threshold for most locations during periods of less transmission, suggesting continued benefit even as infection rates decline. In all transmission periods, the NNT for non–fully vaccinated patients met the clinically meaningful threshold, in contrast to testing of fully vaccinated patients (Table 2). Discussion: Implementing an asymptomatic patient admission testing program can provide clinically relevant value based on the NNT, even during lower periods of transmission and in different patient populations. Limiting admission testing to non–fully vaccinated patients during periods of lower transmission may be a strategy to address cost and resource concerns around this practice. Further investigations into the impact of booster vaccination and newer SARS-CoV-2 variants on admission testing programs are also necessary. Although the impact of such testing on healthcare-associated COVID-19 among patients and healthcare workers could not be clearly determined, these data provide important information as facilities weigh the costs and benefits of such testing.

Funding: None

Disclosures: None

Background: Nursing home (NH) residents and staff were at high risk for COVID-19 early in the pandemic; several studies estimated seroprevalence of infection in NH staff to be 3-fold higher among CNAs and nurses compared to other staff. Risk mitigation added in Fall 2020 included systematic testing of residents and staff (and furlough if positive) to reduce transmission risk. We estimated risks for SARS-CoV-2 infection among NH staff during the first winter surge before widespread vaccination. Methods: Between February and May 2021, voluntary serologic testing was performed on NH staff who were seronegative for SARS-CoV-2 in late Fall 2020 (during a previous serology study at 14 Georgia NHs). An exposure assessment at the second time point covered prior 3 months of job activities, community exposures, and self-reported COVID-19 vaccination, including very recent vaccination (≤4 weeks). Risk factors for seroconversion were estimated by job type using multivariable logistic regression, accounting for interval community-incidence and interval change in resident infections per bed. Results: Among 203 eligible staff, 72 (35.5%) had evidence of interval seroconversion (Fig. 1). Among 80 unvaccinated staff, interval infection was significantly higher among CNAs and nurses (aOR, 4.9; 95% CI, 1.4–20.7) than other staff, after adjusting for race and interval community incidence and facility infections. This risk persisted but was attenuated when utilizing the full study cohort including those with very recent vaccination (aOR, 1.8; 95% CI, 0.9–3.7). Conclusions: Midway through the first year of the pandemic, NH staff with close or common resident contact continued to be at increased risk for infection despite enhanced infection prevention efforts. Mitigation strategies, prior to vaccination, did not eliminate occupational risk for infection. Vaccine utilization is critical to eliminate occupational risk among frontline healthcare providers.

Funding: None

Disclosures: None

Clostridioides difficile infection (CDI) is one of the leading causes of hospital–onset infections. Clinically distinguishing true CDI versus colonization with C. difficile is challenging and often requires reliable and rapid molecular testing methods. At our academic center, we implemented a 2-step testing algorithm to help identify true CDI cases. The University of Mississippi Medical Center is a 700+ bed academic facility located in Jackson, Mississippi. Hospital-onset (HO) CDI was defined based on NHSN Laboratory Identified (LabID) event as the last positive C. difficile test result performed on a specimen using a multistep testing algorithm collected >3 calendar days after admission to the facility. HO-CDI data were collected from all inpatient units except the NICU and newborn nursery. HO-CDI outcomes were assessed based on standardized infection ratio (SIR) data. In May 2020, we implemented a 2-step testing algorithm (Figure 1). All patients with diarrhea underwent C. difficile PCR testing. Those with positive C. difficile PCR test were reflexed to undergo enzyme immunoassay (EIA) glutamate dehydrogenase antigen (Ag) testing and toxin A and B testing. The final results were reported as colonization (C. difficile PCR+/EIA Ag+/Toxin A/B−) or true CDI case (C. difficile PCR+/EIA +/Toxin A/B +) or negative (C. difficile PCR−). All patients with colonization or true infection were placed under contact isolation precautions until diarrhea resolution for 48 hours. During the preintervention period (October 2019–April 2020), 25 HO-CDI cases were reported compared to 8 cases in the postintervention period (June 2020–December 2020). A reduction in CDI SIR occurred in the postintervention period (Q3 2020–Q4 2020, SIR 0.265) compared to preintervention period (Q4 2019–Q1 2020, SIR 0.338) (Figure 2). We successfully reduced our NHSN HO-CDI SIR below the national average after implementing a 2-step testing algorithm for CDI. The 2-step testing algorithm was useful for antimicrobial stewardship to guide appropriate CDI treatment for true cases and for infection prevention to continue isolation of infected and colonized cases to reduce the spread of C. difficile spores.

Funding: No

Disclosures: None

Figure 1.

Figure 2.

Background: In Ghana, treatment of surgical site infections (SSIs) is often empirical and not based on targeted therapy (ie, knowledge of the organisms infecting surgical sites or their susceptibility profiles). This empirical approach most often leads to inappropriate prescription, which is a major driver of antimicrobial resistance. Using phenotypic and molecular tools, we investigated S. aureus, E. coli, K. pneumoniae, and P. aeruginosa recovered from patients with SSIs. Methods: Identification of bacteria species recovered from wound swabs and aspirates was performed using matrix-assisted laser desorption/ionization time-of-flight mass spectroscopy (MALDI-TOF MS). Antimicrobial susceptibility testing (AST) was done using the Kirby-Bauer disk diffusion method. Results were interpreted according to the CLSI 2018 guidelines. Extended-spectrum β-lactamase (ESBL) positivity was detected among the gram-negative isolates using the double disk-diffusion method and PCR amplification of ESBL genes (blaSHV, blaTEM, and blaCTX-M). Staphylococcus aureus isolates resistant to cefoxitin were further tested for the presence of mecA using PCR. Results: In total, 312 patients were enrolled in this prospective study. The 243 bacteria species identified comprised Escherichia coli (34%; 107 of 312), Klebsiella pneumoniae (20%; 62 of 312), Pseudomonas aeruginosa (16%; 49 of 312), and S. aureus (8%; 25 of 312). S. aureus isolates were susceptible to clindamycin, erythromycin, gentamicin, linezolid, rifampicin, and norfloxacin, but 10 S. aureus isolates were resistant to cefoxitin and were positive for the mecA gene (MRSA). Among the 169 isolates in the Enterobactericae category (E. coli and K. pneumoniae), 143 (85%) were resistant to tetracycline; 141 (83%) were resistant to trimethoprim–sulfamethoxazole; 118 (70%) were resistant to cefotaxime; 111 (66%) were resistant to cefuroxime; 98 (58%) were resistant to ciprofloxacin; 86 (51%) were resistant to gentamicin; and 81 (48%) were resistant to chloramphenicol. However, 161 (95%) were sensitive to amikacin and 159 (94%) were sensitive to meropenem. Among the 49 P. aeruginosa isolates, 45 (92%) showed sensitivity to amikacin, 43 (88%) showed sensitivity to meropenem, 35 (71%) showed sensitivity to gentamicin, and 35 (71%) showed sensitivity to ciprofloxacin. ESBL was detected in 59 (55%) of 107 E. coli isolates, and 48 (77%) of 62 K. pneumoniae isolates. blaCTX-M was the dominant ESBL gene in E. coli isolates (34 of 59, 58%). For K. pneumoniae isolates, blaCTX-M genes were detected in 45 (94%) of 48 isolates and blaSHV genes were detected in 44 (92%) of 48 isolates. Among the 49 P. aeruginosa isolates, 3 harbored the blaTEM gene. Conclusions: The findings of high proportions of ESBL-producing bacteria species in Ghana is a grave public health concern. Data generated in this study will inform treatment decisions and policies and appropriate antibiogram development and will support antimicrobial stewardship programs at the respective healthcare facilities in Ghana.

Funding: None

Disclosures: None

Among 37 internal-medicine resident physicians assigned to our outpatient clinic at Minneapolis Veterans’ Affairs Health Care System (MVAHCS) on July 1, 2017, we designed a pre- and postintervention observational study. Our results show that in-person academic detailing around outpatient antimicrobial selection was associated with a decrease in outpatient antimicrobial prescriptions in a group of high-prescribing resident physicians.