SARS-CoV-2 Cycle Thresholds, Poverty, Race, and Clinical Outcomes

BACKGROUND

Poverty and high viral load are associated with worse outcomes among COVID-19 patients.

METHODS

We included patients admitted to Froedtert Health between March 16 and June 1, 2020. SARS-CoV-2 viral load was proxied by cycle-threshold values. To measure poverty, we used Medicaid or uninsured status and residence in socially disadvantaged areas. We assessed the association between viral load and length of stay and discharge disposition, while controlling for demographics and confounders.

RESULTS

Higher viral load was associated with longer length of stay (coefficient -0.02; 95% CI, -0.04 to 0.01; P = 0.006) and higher likelihood of death (coefficient -0.11; 95% CI, -0.17 to -0.06; P < 0.001). Poverty, residence in disadvantaged areas, and race were not.

DISCUSSION

This study confirms a relationship of viral load with in-hospital death, even after controlling for race and poverty.

Antibiotic resistance patterns of Escherichia coli isolates from the clinic through the wastewater pathway

Antimicrobial resistance (AMR) remains one of the leading global health threats. This study compared antimicrobial resistance patterns among E. coli isolates from clinical uropathogenic Escherichia coli (UPEC) to hospital wastewater populations and throughout an urban wastewater treatment facility - influent, pre- and post-chlorinated effluents. Antibiotic susceptibility of 201 isolates were analyzed against eleven different antibiotics, and the presence of twelve antibiotic resistant genes and type 1 integrase were identified. AMR exhibited the following pattern: UPEC (46.8%) > hospital wastewater (37.8%) > urban post-chlorinated effluent (27.6%) > pre-chlorinated effluent (21.4%) > urban influent wastewater (13.3%). However, multi-drug resistance against three or more antimicrobial classes was more prevalent among hospital wastewater populations (29.7%) compared to other sources. E. coli from wastewaters disinfected with chlorine were significantly correlated with increased trimethoprim-sulfamethoxazole resistance in E. coli compared to raw and treated wastewater populations. bla_CTX-M-1 group was the most common extended spectrum beta-lactamase in E. coli from hospital wastewater (90%), although UPEC strains also encoded bla_CTX-M-1 group (50%) and bla_TEM (100%) genes. Among tetracycline-resistant populations, tetA and tetB were the only resistance genes identified throughout wastewater populations that were associated with increased phenotypic resistance. Further characterization of the E. coli populations identified phylogroup B2 predominating among clinical UPEC populations and correlated with the highest AMR, whereas the elevated rate of multi-drug resistance among hospital wastewater was mostly phylogroup A. Together, our findings highlight hospital wastewater as a rich source of AMR and multi-drug resistant bacterial populations.

Duration of carbapenemase-producing Enterobacteriales carriage among ICU patients in Miami, FL: A retrospective cohort study

BACKGROUND

Current recommendations by the Centers for Disease Control and Prevention suggest placing patients with carbapenem-producing Enterobacteriales (CPE) in contact precautions, but there is no consensus on the appropriate duration of precautions.

AIM

We aimed to evaluate predictors for prolonged CPE carriage and median clearance time.

METHODS

Patients with first isolated CPE identified from 2012-2016 were followed for clearance of CPE using at least two rectal or tracheal aspirate surveillance cultures and clinical cultures during intensive-care-unit admission. Predictors associated with prolonged CPE carriage were assessed using Cox proportional-hazards.

RESULTS

Out of 75 eligible patients, 25 (33%) cleared their CPE-carrier status; median time to clearance was 80 days (Range, 16-457). Patients who were immunocompromised, had mechanical ventilation exposure, or exposure to carbapenems had 66%, 66%, and 86% (HR, 0.34, 0.34, and 0.14, respectively [P-value <.05]) lower probability of clearing compared to those immunocompetent of without such exposures. Patients with CPE isolated from more than one body site had a 5.3 times higher probability of clearing their CPE-carrier status (P-value <.001).

CONCLUSIONS

Patients immunocompromised, with mechanical ventilation exposure, or exposure to carbapenems had higher risk for prolonged CPE carriage. Infection prevention programs should consider these predictors as part of their assessment of discontinuing contact precautions among CPE carriers to prevent horizontal transmission and outbreaks within healthcare facilities.

Transmission Dynamics of Clostridioides difficile in 2 High-Acuity Hospital Units

BACKGROUND

The key epidemiological drivers of Clostridioides difficile transmission are not well understood. We estimated epidemiological parameters to characterize variation in C. difficile transmission, while accounting for the imperfect nature of surveillance tests.

METHODS

We conducted a retrospective analysis of C. difficile surveillance tests for patients admitted to a bone marrow transplant (BMT) unit or a solid tumor unit (STU) in a 565-bed tertiary hospital. We constructed a transmission model for estimating key parameters, including admission prevalence, transmission rate, and duration of colonization to understand the potential variation in C. difficile dynamics between these 2 units.

RESULTS

A combined 2425 patients had 5491 admissions into 1 of the 2 units. A total of 3559 surveillance tests were collected from 1394 patients, with 11% of the surveillance tests being positive for C. difficile. We estimate that the transmission rate in the BMT unit was nearly 3-fold higher at 0.29 acquisitions per percentage colonized per 1000 days, compared to our estimate in the STU (0.10). Our model suggests that 20% of individuals admitted into either the STU or BMT unit were colonized with C. difficile at the time of admission. In contrast, the percentage of surveillance tests that were positive within 1 day of admission to either unit for C. difficile was 13.4%, with 15.4% in the STU and 11.6% in the BMT unit.

CONCLUSIONS

Although prevalence was similar between the units, there were important differences in the rates of transmission and clearance. Influential factors may include antimicrobial exposure or other patient-care factors.

Epidemiology of carbapenem-resistant Enterobacteriaceae in hospitals of a large healthcare system in Miami, Florida from 2012 to 2016: Five years of experience with an internal registry

BACKGROUND

Carbapenem-resistant Enterobacteriaceae (CRE) is an urgent public health threat globally. Limited data are available regarding the epidemiology of CRE in South Florida. We describe the epidemiology of CRE within a large public healthcare system in Miami, FL, the experience with an internal registry, active surveillance testing, and the impact of infection prevention practices.

METHODS

Retrospective cohort study in 4 hospitals from a large healthcare system in Miami-Dade County, FL from 2012 to 2016. The internal registry included all CRE cases from active surveillance testing from rectal and/or tracheal screening occurring in the intensive care units of 2 of the hospitals and clinical cultures across the healthcare system. All CRE cases were tagged in the electronic medical record and automatically entered into a platform for automatic infection control surveillance. The system alerted about new cases, readmissions, and transfers.

RESULTS

A total of 371 CRE cases were identified. The overall prevalence was 0.077 cases per 100 patient-admissions; the admission prevalence was 0.019 per 100 patient-admissions, and the incidence density was 1.46 cases per 10,000 patient-days. Rates increased during the first 3 years of the study and declined later to a lower level than at the beginning of study period.

CONCLUSIONS

Active surveillance testing and the use of an internal registry facilitated prompt identification of cases contributing to control increasing rates of CRE by rapid implementation of infection prevention strategies.

Distribution of SARS-CoV-2 PCR Cycle Threshold Values Provide Practical Insight Into Overall and Target-Specific Sensitivity Among Symptomatic Patients

OBJECTIVES

We examined the distribution of reverse transcription polymerase chain reaction (RT-PCR) cycle threshold (CT) values obtained from symptomatic patients being evaluated for coronavirus disease 2019 (COVID-19) to determine the proportion of specimens containing a viral load near the assay limit of detection (LoD) to gain practical insight to the risk of false-negative results. We also examined the relationship between CT value and patient age to determine any age-dependent difference in viral load or test sensitivity.

METHODS

We collected CT values obtained from the cobas severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) assay corresponding to 1,213 combined nasopharyngeal-oropharyngeal specimens obtained from symptomatic individuals that were reported as positive or presumptive positive for SARS-CoV-2. CT values were stratified by SARS-CoV target and patient age group.

RESULTS

In total, 93.3% to 98.4% of specimens demonstrated CT values greater than 3× the assay LoD, at which point false-negative results would not be expected. The mean of CT values between age groups was statistically equivalent with the exception of patients in age group 80 to 89 years, which demonstrated slightly lower CTs.

CONCLUSIONS

Based on the distribution of observed CT values, including the small proportion of specimens with values near the assay LoD, there is a low risk of false-negative RT-PCR results in combined nasopharyngeal-oropharyngeal specimens obtained from symptomatic individuals.

Prevalence of SARS-CoV-2 asymptomatic infections in two large academic health systems in Wisconsin

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) asymptomatic infections may play a critical role in disease transmission. We aim to determine the prevalence of asymptomatic SARS-CoV-2 infection at 2 hospital systems in 2 counties in Wisconsin. The SARS-CoV-2 prevalence was 1% or lower at both systems despite the higher incidence of coronavirus disease 2019 (COVID-19) in Milwaukee County.

The Juncture Between Clostridioides difficile Infection and Inflammatory Bowel Diseases

The detection of Clostridioides difficile in inflammatory bowel disease (IBD) patients is a common occurrence, in part due to the standard clinical practice of testing for the presence of C. difficile during acute IBD exacerbations. Given the clinical overlap between C. difficile infections and acute IBD exacerbations (ie, increased frequency of loose stools, abdominal pain), it is hard to differentiate C. difficile infections versus colonizations in patients with underlying IBD who test positive for C. difficile. Here, we review the epidemiology, clinical presentation, risk factors, diagnosis, treatment, and outcomes of IBD patients with positive C. difficile tests.

Clostridium difficile in Immunocompromised Hosts: A Review of Epidemiology, Risk Factors, Treatment, and Prevention

Clostridium difficile is a significant pathogen in healthcare today, impacting both hospitalized and community-based patients. Immunocompromised patients experience a high incidence of C. difficile infection, ranging from 6% to 33% in the hematology-oncology population and up to 23% among lung transplant recipients, and have a rate of 7.1-8.3 cases per 1000 patient-years in patients with human immunodeficiency virus (HIV). Recurrence of C. difficile infections among immunocompromised patients is also high, with rates up to 40% in both the hematology-oncology population and solid organ transplant recipients. This higher incidence of C. difficile infection and recurrence is believed to be secondary to frequent antimicrobial use, suppressed immune function, increased exposure to healthcare settings, and higher prevalence of C. difficile colonization. This review summarizes published data describing the epidemiology, risk factors for acquisition and infection, treatment, and prevention of C. difficile in hematology-oncology, solid organ transplant, and HIV-infected patients.

1225. How Frequently Should Sink Drains Be Disinfected?

Background

New evidence shows the relevance of sink drains in the horizontal transmission of multidrug-resistant organisms. We recently demonstrated that a peroxide-based disinfectant (product B) was better than bleach at disinfecting sink drains; however, we did not determine the duration of this effect. In this study, we evaluate the duration of bacterial reduction in sink drains treated with product B and compared it to an enhanced hydrogen peroxide agent (product A).

Methods

Testing was performed in a 26-bed medical intensive care unit at a 566-bed tertiary care hospital in Milwaukee, WI. Two disinfectants were compared: product A (hydrogen peroxide, octanoic acid, and peroxyacetic acid; Virasept, Ecolab) and product B (hydrogen peroxide-based disinfectant; Peroxide Multi Surface Cleaner and Disinfectant, Ecolab). Sinks were randomly assigned to product A, product B, and control (no disinfection). On day 0, baseline cultures were obtained and disinfectant agents were applied. On post-intervention days 1, 3, 5, and, 7, samples from each drain were collected using E-swabs (Copan, Italy). Quantitation of Gram-negative burden was determined by serial dilution in saline plated to MacConkey agar and dilutions that contained 20–200 colonies were used for bacterial colony-forming units (CFU).

Multivariate multiple linear regression and analysis of variance were used to compare mean Ln(1+CFU) between groups using R v3.5.0. Environmental sampling, cultures, and statistical analyses were performed blinded to the disinfected used.

Results

All three groups had similar CFU counts at baseline (P > 0.05). On day 1, a statistically significant reduction in bacterial CFUs was observed in the group treated with product A compared with sinks treated with product B (P = 0.04) or the control group (P < 0.01). The same differences were observed on day 3 post-intervention. There were no significant reductions on days 5 and 7.

Conclusion

Product A was the most effective product at disinfecting sink drains but its effect disappeared at 5 days post-disinfection. These results suggest that treating sink drains every 5 days with a hydrogen peroxide mixture would be ideal for healthcare facilities dealing with sink drain contamination.

Disclosures

All authors: No reported disclosures.

534. Active Screening for Carbapenemase Producing Enterobacteriaceae: Yield and Cost Considerations

Background

During 2016, our hospital experienced an outbreak with carbapenemase-producing Enterobacteriaceae (CPE) in our solid-organ transplant (SOT) population. Since this outbreak and until now, our hospital has implemented active CPE screening of patients admitted to SOT units and point prevalence surveillances in any unit with a known CPE patient. The present study evaluates the yield of these screening tests and their cost since implementation.

Methods

This retrospective cohort was performed in a 600-bed hospital in Milwaukee, WI. CPE screening tests were retrieved from the clinical microbiology laboratory dataset from January 2016 to April 2019. CPE tests are performed on rectal swabs or stool samples using the CDC broth enrichment method followed by MIC confirmation using Etest. CPE patients were placed on enhanced precautions (gowns, gloves, booties) and were cohorted geographically and to 1:1 nursing and nurse aid staff.

Results

A total of 6,684 samples belonging to 3,383 patients were processed (1.9 samples/patient). Two hundred thirty (3.44%) had carbapenem-resistant Enterobacteriaceae, although only 33 isolates (0.49%) were confirmed as either KPC (n = 31) or NDM (n = 2) positive. Out of the 3,383 patients tested, 121 were identified as carriers of carbapenem-resistant isolates but only 11 (0.32%) were CPE (KPC = 11; NDM = 2). The incidence of new CPE patients during 2016 was 0.82% but decreased to 0.28% and 0.33% in 2017 and 2018, respectively. The units with the highest number of CPE patients were the transplant intensive care unit (n = 6) and the step-down SOT unit (n = 3). Negative cultures were quoted at $8.49 per sample but culture plates with colonies increased the cost per test to $28.44. The total cost for all the 6,684 screening tests was calculated at $61,335. The cost of CPE screening per positive CPE patient identified comes up to $5,575 (not including RN collection time).

Conclusion

In an institution with staff and CPE patient cohorting, active screening of CPE positive patients was relatively expensive given our low -level of transmission. In the near future, we plan to stop staff and patient cohorting due to the high stress that these interventions place on our hospital staff. This might ensue in increase transmission, which will be detected by CPE screening tests.

Disclosures

All authors: No reported disclosures.

2339. Clostridioides difficile: Impact of Active Screening of Asymptomatic Carriers and Testing Stewardship

Background

We recently implemented a hospital-wide C. difficile testing algorithm and screening/isolation of C. difficile asymptomatic carriers primarily in heme-onc units. We aim to evaluate the impact of these interventions on the epidemiology of C. difficile + tests.

Methods

This retrospective cohort was performed in a 600-bed hospital in Milwaukee, WI, from January 1, 2016 to March 31, 2019. All clinical C. difficile tests included nucleic acid amplification (NAAT; Xpert C. difficile, Cepheid). On February 2017, all NAAT+ tests had toxin (tox) checked (Quick check complete, Alere). Testing algorithm (Figure 1) started mid 2016 until now. Screening phases included: Phase 1 (September 2016–May 2017): C. difficile screening cultures shared with units but not placed in electronic medical records (EMR). Patients + placed on enteric precautions (gown, gloves, hand hygiene). Phase 2 (May 2017–January 2018): C. difficile screening (NAAT) performed on admission and weekly thereafter, results placed in EMR, NAAT+ patients placed on enteric precautions. Phase 3 (January 2018–present): C. difficile screening (NAAT) on admission, results placed in EMR, NAAT+ patients placed on enteric precautions. Federal reporting changed to only reporting NAAT+tox+. Tests (NAAT+, NAAT+tox+, and NAAT+tox-) were analyzed using Poisson regression offsetting for log of patient-days using SAS, v9.4.

Results

Hospital-wide C. difficile tests decreased from 21 to 10.9 tests per 1,000 patient-days (P < 0.0001; Figure 2). This effect was seen in heme-onc units (41 to 15.7; P < 0.0001; Figure 3) and in all other units (18.9 to 9.9; P < 0.0001). All NAAT+ results decreased from 2.99 to 1.94 per 1,000 patient-days hospital wide (P < 0.0001) but remained unchanged in heme-onc units (4.6 to 3.7, P > 0.05). NAAT+tox+ results remained unchanged hospital wide and in heme-onc units (0.8 to 0.7 and 1.1 to 1.2, respectively; both P > 0.05); however, the frequency of NAAT+tox− tests decreased hospital wide (1.8 to 1.3; P = 0.0003) and in heme-onc units (3.8 to 2.4; P = 0.05).

Conclusion

A C. difficile testing algorithm was successful decreasing the number of C. difficile tests performed and had a hospital-wide reduction of NAAT+tox− tests. The rate of NAAT+tox+ cases in heme-onc units and hospital wide remained unchanged despite active screening and isolation in selected units.

Disclosures

All authors: No reported disclosures.

2399. Ribotype Diversity of Clostridioides difficile strains obtained during screening tests

Background

Clostridioides difficile is an organism acquired not only in healthcare settings but also in community settings. For the past several years our hospital has performed screening tests to detect asymptomatic carriage of C. difficile. We now aim to better understand the ribotypes and degree of diversity among these C. difficile strains obtained in a systematic screening.

Methods

This study was performed at a 600 bed teaching affiliated hospital in Milwaukee, WI, where surveillance testing is performed in selected units upon admission and weekly thereafter using nucleic acid amplification test (NAAT; Xpert® C. difficile; Cepheid, Sunnyvale, CA). Screening tests are obtained regardless of symptoms. NAAT positive samples underwent anaerobic cultures in C. difficile selective broth (CCMB-TAL) for 24–48 hr and then to Brucella blood agar plates (BA) for 48–72 hr to confirm C. difficile presence. PCR-ribotyping was performed as previously described by Stubbs et al. with minor modifications. The results were compared with a database containing >3,000 clinical isolates including C. difficile reference strains from the Cardiff ribotype collection.

Results

A total of 104 strains belonging to 93 unique patients were processed. Patients had a mean age of 60 years (range: 18 - 89) and 49% were females. Most patients were hospitalized in the hematology oncology units (55.7%) or in the solid-organ transplant step down unit (9.6%). A total of 25 different ribotypes were identified. The most common ribotype was 014/020 (23; 22%), followed by ribotype 56 (13; 12.5%), 106 (12; 11.5%), 027 (11; 10.5%), 002 (6; 5.7%), and 078/126 (5; 4.81).

Regarding the timing of admission, 70 strains were obtained within 4 days from hospital admission and the remaining 34 were obtained afterwards. Both groups had ribotype 014/020 as the most frequently detected ribotype but 027 were the second most commonly detected at the time of admission (table). A total of 7 patients had more than one stool sample processed and 5 of them had discordant ribotypes at different time points.

Conclusion

Systematic screening tests for C. difficile carriage in a single center showed a large heterogeneity of ribotypes with the majority not being 027. Additionally, most patients tested more than once carried different ribotypes.

Disclosures

All authors: No reported disclosures.

The relevance of sink proximity to toilets on the detection of Klebsiella pneumoniae carbapenemase inside sink drains

We report a higher prevalence of bla_KPC in patient room sink drains located next to toilets (87.0%) when compared with sink drains located farther away from toilets (21.7%) using direct polymerase chain reaction assay. However, culture methods were only able to recover bla_KPC-positive isolates from 16% of polymerase chain reaction-positive drains.

1192. Identification of a Novel Enterobacter cloacae Isolate Producing an IMP-13 Metallo-β-Lactamase

Background

Metallo-β-lactamases (MBLs) have been identified as emerging resistance determinants in Enterobacteriaceae, A. baumanii, and P. aeruginosa. Early identification of carbapenemase-producing organisms (CPOs) is essential to prevent dissemination within healthcare settings. We report a case of a patient who was blood culture positive for a multidrug-resistant E. cloacae which was subsequently found to be positive for the MBL bla_IMP-13.

Methods

A 74-year-old female, with no significant past medical or travel history, developed sepsis 2 days after undergoing debulking surgery for stage IIIc ovarian carcinoma. Blood cultures were positive for Gram-negative bacilli and the organisms identified as Enterobacter spp. with bla_IMP MBL (Verigene). Antimicrobial susceptibility testing demonstrated high-level resistance to all penicillins, ureidopenicillins, cephalosporins, and β-lactam/inhibitor antibiotics, and susceptibility to colistin, tigecycline, and monobactams.

Results

Further testing using micro-broth dilution, BD phoenix, and Etest, demonstrated susceptible MICs to meropenem and imipenem, with intermediate to resistant MICs to ertapenem. The patient was treated with a combination therapy of amikacin, aztreonam, and ceftazidime-avibactam and responded clinically. Per standard protocol, the organism was sent to WI Laboratory of Hygiene for further characterization. Phenotypic testing using the modified carbapenem inactivation test (mCIM) was positive, indicating the presence of a carbapenemase; however, results using Xpert CarbaR (Cepheid) were negative. Subsequent sequencing of the isolate confirmed the presence of bla_IMP-13.

Conclusion

This was an important case for several reasons. First, bla_IMP-13 is historically reported in Pseudomonas aeruginosa. Indeed, this was the first report of Enterobacteriaceae harboring bla_IMP in WI. Second, it had unique susceptibility pattern to carbapenems and was not detected by the CarbaR. Third, these data demonstrate clinical success in treating an MBL CPO with a combination anti-microbial regimen, based on an understanding of resistance mechanisms involved. This report calls for more vigilant screening for CPO using both phenotypic and genotypic methods.

Disclosures

N. Ledeboer, Luminex: Consultant, Consulting fee.

The Intersection Between Colonization Resistance, Antimicrobial Stewardship, and Clostridium difficile

PURPOSE OF REVIEW

Colonization resistance refers to the innate defense provided by the indigenous microbiota against colonization by pathogenic organisms. We aim to describe how this line of defense is deployed against Clostridium difficile and what the implications are for interventions directed by Antimicrobial Stewardship Programs.

RECENT FINDINGS

The indigenous microbiota provides colonization resistance through depletion of nutrients, prevention of access to adherence sites within the gut mucosa, production of inhibitory substances, and stimulation of the host's immune system. The ability to quantify colonization resistance could provide information regarding periods of maximal vulnerability to colonization with pathogens and also allow the identification of mechanisms of restoration of colonization resistance. Methods utilized to determine the composition of the gut microbiota include sequencing technologies and measurement of concentration of specific bacterial metabolites. Use of innovations in the quantification of colonization resistance can expand the role of Antimicrobial Stewardship from prevention of disruption of the indigenous microbiota to restoration of colonization resistance.

Elizabethkingia anophelis: Clinical Experience of an Academic Health System in Southeastern Wisconsin

In late 2015 and early 2016, 11 patients were identified with cultures positive for Elizabethkingia anophelis in our health system. All patients had positive blood cultures upon admission. Chart review showed that all had major comorbidities and recent health care exposure. The attributable mortality rate was 18.2%.

Prevalence of Clostridium difficile and Multidrug Resistant Gram-negative Rods in the Soil from Southeastern Wisconsin

Background

Preliminary data suggests that community-onset Clostridium difficile might be more common in rural areas. Thus, farms—specifically livestock farms—might be a major reservoir of C. difficile. Similarly, antibiotic exposures might predispose farm animals for colonization with multidrug resistant Gram-negative organisms. The aim of this study was to determine the prevalence of C. difficile and multidrug resistant gram-negative rods in the soil of Southeastern Wisconsin farms.

Methods

From July to September of 2016, soil samples were collected from farms with livestock animals. Soil samples were collected using gloves and sample containers. Soil samples were collected from farms specifically in or near Washington, Waukesha, and Milwaukee counties which are within the proximity of Milwaukee Metro area. Soil samples were cultured for C. difficile and Gram-negative rods on selective plates and by broth enrichment.

Results

A total of 20 farms participated in this study with a total of 40 soil samples. Out of the 40 soil samples, 20 were from an area where animals roam or where manure was used and the remaining 20 were from an area where animals are prohibited or where there was no manure. Out of the 20 soil samples where animals roam, 10 (50%), tested positive for C. difficile. Out of 20 soil samples where animals are prohibited, 13 samples (65%) tested positive for C. difficile. 2 of the 23 C. difficile isolates recovered were toxigenic. Eight (40%) of the 20 soil samples where animals roam tested positive for fluoroquinolone-resistant bacteria (FQR). While 5 (25%) of the 20 soil samples where animals are prohibited, tested positive for FQR bacteria. An Acinetobacter calcoaceticus was found to exhibit carbapenem-resistance.

Conclusion

We found soil colonization with C. difficile and FQR in 65% and 25%, respectively, where animals are prohibited. Where animals roam we found C. difficile and FQR 50% and 40%, respectively. Our study suggests that farms may be a significant community source for C. difficile and fluoroquinolone resistant organisms. Additional testing should be done to examine factors that might be increasing antibiotic resistance in farms (e.g., antibiotic exposure).

Disclosures

All authors: No reported disclosures.

Environmental Exposure to Carbapenem-Resistant Acinetobacter baumannii as a Risk Factor for Patient Acquisition of A. baumannii

We aimed to determine the association between environmental exposure to carbapenem-resistant Acinetobacter baumannii and the subsequent risk of acquiring this organism. Patients exposed to a contaminated hospital environment had 2.77 times the risk of acquiring carbapenem-resistant A. baumannii than did unexposed patients (relative risk, 2.77 [95% confidence interval, 1.50–5.13]; P = .002).

Randomized Crossover Study Evaluating the Effect of a Hand Sanitizer Dispenser on the Frequency of Hand Hygiene among Anesthesiology Staff in the Operating Room

Forty anesthesia providers were evaluated with and without hand sanitizer dispensers present on the anesthesia machine. Having a dispenser increased the frequency of hand hygiene only from 0.5 to 0.8 events per hour (P = .01). Other concomitant interventions are needed to further increase hand hygiene frequency among anesthesia providers.

Infect Control Hosp Epidemiol 2014;35(6):717–720

A New Approach to Pathogen Containment in the Operating Room: Sheathing the Laryngoscope After Intubation

BACKGROUND

Anesthesiologists may contribute to postoperative infections by means of the transmission of blood and pathogens to the patient and the environment in the operating room (OR). Our primary aims were to determine whether contamination of the IV hub, the anesthesia work area, and the patient could be reduced after induction of anesthesia by removing the risk associated with contaminants on the laryngoscope handle and blade. Therefore, we conducted a study in a simulated OR where some of the participants sheathed the laryngoscope handle and blade in a glove immediately after it was used to perform an endotracheal intubation.

METHODS

Forty-five anesthesiology residents (postgraduate year 2-4) were enrolled in a study consisting of identical simulation sessions. On entry to the simulated OR, the residents were asked to perform an anesthetic, including induction and endotracheal intubation timed to approximately 6 minutes. Of the 45 simulation sessions, 15 were with a control group conducted with the intubating resident wearing single gloves, 15 with the intubating resident using double gloves with the outer pair removed and discarded after verified intubation, and 15 wearing double gloves and sheathing the laryngoscope in one of the outer gloves after intubation. Before the start of the scenario, the lips and inside of the mouth of the mannequin were coated with a fluorescent marking gel. After each of the 45 simulations, an observer examined the OR using an ultraviolet light to determine the presence of fluorescence on 25 sites: 7 on the patient and 18 in the anesthesia environment.

RESULTS

Of the 7 sites on the patient, ultraviolet light detected contamination on an average of 5.7 (95% confidence interval, 4.4-7.2) sites under the single-glove condition, 2.1 (1.5-3.1) sites with double gloves, and 0.4 (0.2-1.0) sites with double gloves with sheathing. All 3 conditions were significantly different from one another at P < 0.001. Of the 18 environmental sites, ultraviolet light detected fluorescence on an average of 13.2 (95% confidence interval, 11.3-15.6) sites under the single-glove condition, 3.5 (2.6-4.7) with double gloves, and 0.5 (0.2-1.0) with double gloves with sheathing. Again, all 3 conditions were significantly different from one another at P < 0.001.

CONCLUSIONS

The results of this study suggest that when an anesthesiologist in a simulated OR sheaths the laryngoscope immediately after endotracheal intubation, contamination of the IV hub, patient, and intraoperative environment is significantly reduced.

Double gloves: a randomized trial to evaluate a simple strategy to reduce contamination in the operating room

BACKGROUND

Oral flora, blood-borne pathogens, and bacterial contamination pose a direct risk of infection to patients and health care workers. We conducted a study in a simulated operating room using a newly validated technology to determine whether the use of 2 sets of gloves, with the outer set removed immediately after endotracheal intubation, may reduce this risk.

METHODS

Forty-one anesthesiology residents (PGY 2-4) were enrolled in a study consisting of individual or group simulation sessions. On entry to the simulated operating room, the residents were asked to perform an anesthetic induction and tracheal intubation timed to approximately 6 minutes; they were unaware of the study design. Of the 22 simulation sessions, 11 were conducted with the intubating resident wearing single gloves, and 11 with the intubating resident using double gloves with the outer pair removed after verified intubation. Before the start of the scenario, we coated the lips and inside of the mouth of the mannequin with a fluorescent marking gel as a surrogate pathogen. After the simulation, an observer examined 40 different sites using a handheld ultraviolet light in the operating room to determine the transfer of surrogate pathogens to the patient and the patient's environment. Residents who wore double gloves were instructed by a confederate nurse to remove the outer set immediately after completion of the intubation. Forty sites of potential intraoperative pathogen spread were identified and assigned a score.

RESULTS

The difference in the rate of contamination between anesthesiology residents who wore single gloves versus those with double gloves was clinically and statistically significant. The number of sites that were contaminated in the operating room when the intubating resident wore single gloves was 20.3 ± 1.4 (mean ± SE); the number of contaminated sites when residents wore double gloves was 5.0 ± 0.7 (P < 0.001).

CONCLUSIONS

The results of this study suggest that when an anesthesiologist wears 2 sets of gloves during laryngoscopy and intubation and then removes the outer set immediately after intubation, the contamination of the intraoperative environment is dramatically reduced.

Clinical Outcomes of Carbapenem-Resistant Acinetobacter baumannii Bloodstream Infections: Study of a 2-State Monoclonal Outbreak

Objective.

To characterize the clinical outcomes of patients with bloodstream infection caused by carbapenem-resistant Acinetobacter baumannii during a 2-state monoclonal outbreak.

Design.

Multicenter observational study.

Setting.

Four tertiary care hospitals and 1 long-term acute care hospital.

Methods.

A retrospective medical chart review was conducted for all consecutive patients during the period January 1, 2005, through April 30, 2006, for whom 1 or more blood cultures yielded carbapenem-resistant A. baumannii.

Results.

We identified 86 patients from the 16-month study period. Their mortality rate was 41%; of the 35 patients who died, one-third (13) had positive blood culture results for carbapenem-resistant A. baumannii at the time of death. Risk factors associated with mortality were intensive care unit stay, malignancy, and presence of fever and/or hypotension at the time blood sample for culture was obtained. Only 5 patients received adequate empirical antibiotic treatment, but the choice of treatment did not affect mortality.

Fifty-seven patients (66.2%) had a single positive blood culture result for carbapenem-resistant A. baumannii; the only factor associated with a single positive blood culture result was the presence of decubitus ulcers. Interestingly, during the study period, a transition from single to multiple positive blood culture results was observed. Four patients, 3 of whom were in a burn intensive care unit, were bacteremic for more than 30 days (range, 36–86 days).

Conclusions.

To our knowledge, this is the first time a study has described 2 patterns of bloodstream infection with A. baumannii: single versus multiple positive blood culture results, as well as a subset of patients with prolonged bacteremia.

Four Years of Surveillance Cultures at a Long-Term Acute Care Hospital

Objective.

To characterize the degree of colonization with multidrug-resistant organisms (MDROs) among patients admitted to a long-term acute care hospital.

Design.

Ecologie Study.

Setting.

A 70-bed long-term acute care hospital (a hospital within a hospital) in the greater Chicago area.

Methods.

As part of an infection control initiative, specimens were collected from all consecutively admitted patients for culture of MDROs within 72 hours of admission. Cultures from July 28, 2005, through November 1, 2008, were analyzed on the basis of the bodily site from which the isolate was recovered and the organisms identified. If MDROs were yielded by culture of specimens that were obtained from 24 hours to 30 days after collection of the patient's original set of specimens, these MDROs were removed from the analysis. In addition, repeat rectal swab samples were collected for culture at 2 weeks after admission for all consecutive patients admitted from January 1 through March 31, 2007.

Results.

A total of 1,739 patients with a total of 5,198 specimens met entry criteria. Of the corresponding 5,198 surveillance cultures, 1,580 (30%) were positive for MDROs. Of the 1,739 patients, 947 (54%) had a culture-positive specimen recovered from any site. Vancomycin-resistant Enterococcus was the organism most commonly isolated in cultures of rectal swab samples (in 38% of such cultures) and wounds (in 18% of such cultures). The rate of rectal carriage of vancomycin-resistant Enterococcus increased from 29% in 2005 to 44% in 2008.