Carbapenem-resistant Enterobacterales in Children at 18 US Health Care System Study Sites: Clinical and Molecular Epidemiology From a Prospective Multicenter Cohort Study

Background

Carbapenem-resistant Enterobacterales (CRE) are an urgent public health threat in the United States.

Objective

Describe the clinical and molecular epidemiology of CRE in a multicenter pediatric cohort.

Methods

CRACKLE-1 and CRACKLE-2 are prospective cohort studies with consecutive enrollment of hospitalized patients with CRE infection or colonization between 24 December 2011 and 31 August 2017. Patients younger than age 18 years and enrolled in the CRACKLE studies were included in this analysis. Clinical data were obtained from the electronic health record. Carbapenemase genes were detected using polymerase chain reaction and whole-genome sequencing.

Results

Fifty-one children were identified at 18 healthcare system study sites representing all U.S. census regions. The median age was 8 months, with 67% younger than age 2 years. Median number of days from admission to culture collection was 11. Seventy-three percent of patients had required intensive care and 41% had a history of mechanical ventilation. More than half of children had no documented comorbidities (Q1, Q3 0, 2). Sixty-seven percent previously received antibiotics during their hospitalization. The most common species isolated were Enterobacter species (41%), Klebsiella pneumoniae (27%), and Escherichia coli (20%). Carbapenemase genes were detected in 29% of isolates tested, which was lower than previously described in adults from this cohort (61%). Thirty-four patients were empirically treated on the date of culture collection, but only 6 received an antibiotic to which the CRE isolate was confirmed susceptible in vitro. Thirty-day mortality was 13.7%.

Conclusions

CRE infection or colonization in U.S. children was geographically widespread, predominantly affected children younger than age 2 years, associated with significant mortality, and less commonly caused by carbapenemase-producing strains than in adults.

1756. Prescriber Adherence to System-Wide Urinary Tract Infection Guidelines in Ambulatory Care Clinics

Background

Antimicrobial stewardship (AMS) practices are well established in acute care, only recently expanding into ambulatory care settings. It has been estimated that 80-90% of antibiotic use occurs in the ambulatory setting with up to 52% of that use being unnecessary. Urinary tract infections (UTIs) are commonly treated in ambulatory settings, and drug selection and duration of therapy vary among different practices. Our study evaluated the impact of a system-wide guideline and prescriber education, two recommended AMS strategies, on antibiotic utilization for UTIs in the ambulatory setting.

Methods

This retrospective study evaluated female adult patients prescribed an antibiotic for acute uncomplicated cystitis by a primary care provider at a clinic within our organization between January and March 2021. System-wide UTI treatment guidelines were implemented in November 2020, with live education delivered to primary care prescribers in December 2020. The primary objective of this study was to assess prescriber adherence to system-wide guidelines. The secondary objective was to evaluate utilization of antibiotic regimens for treatment of acute uncomplicated cystitis.

Results

A total of 100 patients were evaluated. Guideline adherence was met in 49% of patients. The primary reason for guideline non-adherence was duration of therapy, which was inappropriate (too long) in 42% of patients. Nitrofurantoin, the first-line antibiotic recommendation on the system-wide guideline, was the antibiotic prescribed most frequently (48%), but was the antibiotic of choice in 90% of patients. Sulfamethoxazole/trimethoprim was prescribed in 35% of patients and was most often prescribed correctly with respect to appropriate dose and duration of therapy (60%), followed by nitrofurantoin (54%). Recurrent cystitis within 30 days occurred in 11% of patients.

Conclusion

Implementation of a system-wide guideline and prescriber education for treatment of UTIs in the ambulatory setting identified areas for future optimization of antibiotic use, namely first line antibiotic selection and duration of therapy. This data will be shared with our prescribers to continue to encourage guideline-adherent antibiotic use.

Disclosures

All Authors: No reported disclosures.

Accessory Genomes Drive Independent Spread of Carbapenem-Resistant Klebsiella pneumoniae Clonal Groups 258 and 307 in Houston, TX

Carbapenem-resistant Klebsiella pneumoniae (CRKp) is an urgent public health threat. Worldwide dissemination of CRKp has been largely attributed to clonal group (CG) 258. However, recent evidence indicates the global emergence of a CRKp CG307 lineage. Houston, TX, is the first large city in the United States with detected cocirculation of both CRKp CG307 and CG258. We sought to characterize the genomic and clinical factors contributing to the parallel endemic spread of CG258 and CG307. CRKp isolates were collected as part of the prospective, Consortium on Resistance against Carbapenems in Klebsiella and other Enterobacterales 2 (CRACKLE-2) study. Hybrid short-read and long-read genome assemblies were generated from 119 CRKp isolates (95 originated from Houston hospitals). A comprehensive characterization of phylogenies, gene transfer, and plasmid content with pan-genome analysis was performed on all CRKp isolates. Plasmid mating experiments were performed with CG307 and CG258 isolates of interest. Dissection of the accessory genomes suggested independent evolution and limited horizontal gene transfer between CG307 and CG258 lineages. CG307 contained a diverse repertoire of mobile genetic elements, which were shared with other non-CG258 K. pneumoniae isolates. Three unique clades of Houston CG307 isolates clustered distinctly from other global CG307 isolates, indicating potential selective adaptation of particular CG307 lineages to their respective geographical niches. CG307 strains were often isolated from the urine of hospitalized patients, likely serving as important reservoirs for genes encoding carbapenemases and extended-spectrum β-lactamases. Our findings suggest parallel cocirculation of high-risk lineages with potentially divergent evolution. IMPORTANCE The prevalence of carbapenem-resistant Klebsiella pneumoniae (CRKp) infections in nosocomial settings remains a public health challenge. High-risk clones such as clonal group 258 (CG258) are particularly concerning due to their association with blaKPC carriage, which can severely complicate antimicrobial treatments. There is a recent emergence of clonal group 307 (CG307) worldwide with little understanding of how this successful clone has been able to adapt while cocirculating with CG258. We provide the first evidence of potentially divergent evolution between CG258 and CG307 with limited sharing of adaptive genes. Houston, TX, is home to the largest medical center in the world, with a large influx of domestic and international patients. Thus, our unique geographical setting, where two pandemic strains of CRKp are circulating, provides an indication of how differential accessory genome content can drive stable, endemic populations of CRKp. Pan-genomic analyses such as these can reveal unique signatures of successful CRKp dissemination, such as the CG307-associated plasmid (pCG307_HTX), and provide invaluable insights into the surveillance of local carbapenem-resistant Enterobacterales (CRE) epidemiology.

122. Optimization of Antibiotic Time-Outs Within a Health System

Background

The Infectious Diseases Society of America estimates that up to 50% of antibiotic use in hospitals is inappropriate. In order to assist with reducing inappropriate antibiotic use, the Centers for Disease Control and Prevention has recommended systemic evaluation of ongoing antibiotic therapy need, such as antibiotic time-outs (ATOs), be implemented. This has further been supported by the Joint Commission in their antimicrobial stewardship medication management standard. Our system implemented a prescriber-led ATO process in 2018, but documented completion of the ATO remained low. Due to this, pharmacists were integrated into the ATO process with the goal of increasing completion rates.

Methods

This pre-post interventional study analyzed the impact of an antibiotic time out process implemented for patients receiving piperacillin/tazobactam (P/T) or cefepime (CEF) for a minimum of 48 hours. The pre-group (Jan-April 2018) had ATOs completed by the primary medical team, while pharmacists completed the ATO in the post group (Jan-April 2020). For each group, a computerized alert prompted completion of the ATO in the electronic health record (EHR). The alert included systematic questions to assess the need for continued P/T and CEF use. The primary outcome was percentage of ATO documentation completed. Secondary outcomes included inappropriate continuation of P/T and CEF and de-escalation within 24 hours after ATO completion.

Results

A total of 248 and 234 patients in the pre- and post-groups were included, respectively. Significantly more ATOs were documented in the post-group compared to the pre-group (65.5% vs 48.5%, p< 0.001). Similarly, inappropriate continuation of P/T and CEF after the ATO process was significantly lower in the post-group compared to the pre-group (11.6% vs 64.0%, p< 0.001). While not statistically significant, there was a trend toward increased de-escalation in the post-group within 24 hours of ATO completion (58.9% vs 47.9%, p=0.105).

Conclusion

A pharmacist-led ATO process reduced inappropriate use of P/T and CEF compared to a prescriber-led process. Incorporating pharmacists into an ATO process may optimize antimicrobial stewardship outcomes.

Disclosures

All Authors: No reported disclosures

1421. Empiric Fluoroquinolone Prescribing Trends for Cystitis in Primary Care

Background

Understanding outpatient antibiotic prescribing practices for urinary tract infections (UTIs) is vital in guiding future stewardship initiatives. Focusing on fluoroquinolones (FQs) is of value as FQs are commonly prescribed, but not recommended as first line therapy by the Infectious Diseases Society of America (IDSA) cystitis treatment guidelines and are also associated with multiple adverse effects. Boxed warnings state FQs should be reserved for patients with no alternative treatment options, due to risk of aortic dissection, C. difficile infection, antimicrobial resistance as well as tendon, joint, muscle, and nervous system damage.

Methods

This descriptive study assessed rates of guideline concordant empiric FQ prescribing from March 1 to June 30, 2019. Adult women prescribed an oral FQ for acute uncomplicated cystitis at a primary care clinic were included. Men, pregnant or breastfeeding women, and patients with pyelonephritis, urologic abnormality, or antibiotic use in the past 30 days were excluded. The primary outcome was the incidence of IDSA guideline concordance among FQs empirically prescribed. Guideline concordant empiric FQ therapy was defined as correct drug, dose, duration and frequency per IDSA guidelines when no first line drug is indicated due to allergy, adverse effect, previous treatment failure or most recent previous urine culture showing bacterial resistance. Secondary outcomes were mean dose (mg), mean duration (days) and incidence of adverse effects.

Results

Of 95 FQ prescriptions included, none met the primary outcome definition. Rates of guideline concordance for each component of the primary outcome definition were 6% for drug selection, 38% for dose, 37% for duration, and 99% for frequency. Mean daily doses exceeded guideline recommended doses by 62% and 100% for ciprofloxacin and levofloxacin, respectively. Mean duration was 5 days, 66% longer than 3 days as recommended by IDSA guidelines. Of 66 patients with documented follow up within 30 days, 3 (5%) experienced an adverse effect, and none developed C. difficile infection.

Conclusion

Current outpatient FQ prescribing for acute uncomplicated cystitis does not align with IDSA guidelines. Multifaceted antimicrobial stewardship initiatives are required to improve appropriate FQ use.

Disclosures

All Authors: No reported disclosures

94. Implementation of Antibiotic Prescribing Scorecards in the Ambulatory Care Setting

Background

Up to 56% of antibiotics prescribed in the ambulatory setting in the United States are inappropriately prescribed, with 30% of those determined to be unnecessary. In order to increase transparency and education about antibiotic prescribing in our ambulatory clinics at our institution, we implemented quarterly scorecards demonstrating antibiotic prescribing trends for primary care prescribers.

Methods

This pre-post interventional study analyzed the impact of prescriber scorecards on antibiotic prescribing, with the intervention consisting of real-time education and presentation of baseline data via scorecards. Prescribers were educated on the scorecard project via live meetings in Nov-Dec 2020. In Dec 2020, prescribers were sent individual emails describing their baseline antibiotic prescription rate (defined as number of prescriptions per 100 patient encounters), de-identified comparison data for other prescribers within their individual clinic, and average rate of the top 10% of prescribers with the lowest prescription rates. Baseline data was from prescriptions dated Jan-Mar 2020. The email also explained the project and shared that quarterly scorecards would be distributed in 2021. Baseline data was compared to prescription data from Jan-Mar 2021. Knowing the COVID-19 pandemic resulted in significantly fewer encounters for respiratory infections, data was also analyzed with respiratory diagnoses removed from the dataset.

Results

In the pre-intervention period, 11,769 antibiotics were prescribed during 92,239 encounters for a prescription rate of 12.8 (95%CI: 12.5-13.0). Of 96,449 encounters in the post-intervention period, 7,326 antibiotics were prescribed for a rate of 7.6 (95%CI: 7.4-7.8; p< 0.0001). When respiratory diagnoses were removed, prescription rates were 6.1 (95%CI: 5.9-6.2) in the pre-group, compared to 6.3 (95%CI: 6.1-6.5; p=0.0546). When analyzed by prescriber, significant decreases were seen in prescriptions by physicians (5.8 vs 5.4, p=0.0035) while increases were seen in prescriptions by advanced practice prescribers.

Conclusion

Antibiotic scorecards sent to prescribers may result in reduced antibiotic prescribing, but further research is needed to elucidate the impact of the scorecards in light of the COVID-19 pandemic.

Disclosures

All Authors: No reported disclosures

Impact of an Antimicrobial Stewardship Program Pharmacist During Microbiology Rounds

OBJECTIVES

The purpose of this study is to describe and evaluate the impact of the participation of an antimicrobial stewardship program (ASP) pharmacist in microbiology rounds at our institution.

METHODS

This single-center retrospective descriptive study included inpatient and ambulatory adults (≥18 years) with a susceptibility request reviewed during microbiology rounds between October 2018 and March 2019. In October 2018, multidisciplinary telephone microbiology rounds were initiated with the medical directors of the clinical microbiology laboratory and ASP pharmacist to review susceptibility requests. Numbers and types of interventions made by an ASP pharmacist and potential benefits were recorded and analyzed.

RESULTS

Sixty-seven susceptibility requests were reviewed by an ASP pharmacist, of which 83.6% were inpatient. An ASP pharmacist completed chart reviews for 92.5% of requests and contacted the requester or primary team 74.6% of the time. About half (47.8%) of susceptibility requests were approved, and only 65.2% of requests from an infectious diseases provider were approved (P = .039). The most frequent potential benefits of the intervention included preventing unnecessary susceptibility testing (47.8%), improving clinician understanding (40.3%), and preventing treatment of a culture result deemed as a contaminant (19.4%).

CONCLUSIONS

ASP pharmacists are uniquely accessible and able to assist with preventing unnecessary susceptibility testing, optimizing antimicrobial therapy, and providing education to other health care professionals.

1374. Carbapenem-Resistant Enterobacterales Infection in Children: Clinical and Molecular Data from a Prospective Multicenter Cohort Study

Background

Carbapenem Resistant Enterobacterales (CRE) are an urgent public health threat. We describe the clinical and molecular epidemiology of CRE infection in a multicenter pediatric cohort.

Methods

Patients under 18 years of age with CRE positive cultures between April 30 2016 and August 31 2017 were identified from among 49 hospitals participating in the Consortium on Resistance Against Carbapenems in Klebsiella and Other Enterobacteriaceae. Isolates representing colonization or infection were included. Bacterial identification and antimicrobial susceptibility testing were performed in each contributing clinical microbiology laboratory. Carbapenem resistance was defined per CDC criteria as those isolates displaying imipenem, doripenem, or meropenem MIC ≥4 μg/mL or ertapenem MIC ≥2 μg/mL. Clinical and epidemiological data were obtained from the electronic health record. Carbapenemase genes were detected using PCR.

Results

51 pediatric patients with CRE were identified at 17 hospitals. All regions of the United States were represented, with highest prevalence in the South (46%), followed by the Northeast (24%), Midwest (20%) and West (10%). The mean age at time of positive culture was 4 years. 66% of children were under age 2. 53% were male. 40% were white, 38% black, and 18% Hispanic. Mean time from admission to culture was 25 days. 72% of children were in an ICU at the time of culture, including 18% in the neonatal ICU. 42% required mechanical ventilation prior to culture. History of malignancy was present in 14% of children. The most common source was urine (31%), followed by respiratory (25%), and blood (18%). The most common species were Enterobacter cloacae (29%), Klebsiella pneumoniae (24%) and E. coli (20%). Carbapenemase genes were detected in 8 out of 35 (23%) isolates tested. 90-day mortality was 18%. Mortality was highest for K. pneumoniae (42%). The majority of subjects (88%) did not receive effective antibiotic therapy on the day of culture collection.

Table 1

Table 2

Conclusion

CRE infection or colonization in children in the U.S. was geographically widespread, likely hospital-acquired, and associated with high mortality. A significant portion of patients were infants. Ineffective antibiotic therapy was common at illness onset.

Disclosures

W. Charles Huskins, MD, MSc, ADMA Biologics (Consultant)Pfizer, Inc (Consultant)

Assessing Pharmacy Students' and Preceptors' Understanding of and Exposure to Antimicrobial Stewardship Practices on Introductory Pharmacy Practice Experiences

Antimicrobial stewardship (AMS) is commonly employed, and may be required, in multiple healthcare settings, with pharmacists playing an integral role in developing and conducting AMS techniques. Despite its prevalence, AMS is minimally taught in pharmacy school curricula. In order to increase student and preceptor understanding and application of AMS techniques, the Medical College of Wisconsin School of Pharmacy required introductory pharmacy practice students to complete three checklists and reflections of AMS techniques observed at three different practice settings: inpatient, ambulatory, and community (retail) pharmacy. Student and preceptor understanding and application of AMS techniques were then assessed via voluntary survey. Survey response rates were 43% for pharmacy students, while preceptor response rates were 27%. Student understanding and application of AMS techniques increased after completion of the AMS checklist, with the largest magnitude of change seen with antibiotic selection recommendations and guideline and policy development. Preceptor understanding was minimally impacted by the activity; however, an increase in understanding was seen for allergy assessments, antibiotic time-outs, and vaccine assessments and recommendations. AMS is an important component of pharmacy practice today. Implementation of a checklist and reflection activity within experiential education increases perceived student understanding and application of relevant AMS techniques.

1045. Impact of an Antimicrobial Stewardship Pharmacist on Microbiology Rounds

Background

Microbiology rounds is an area for antimicrobial stewardship programs (ASP) to potentially intervene on antimicrobial prescribing in both the inpatient and outpatient settings. The purpose of this study was to describe and evaluate the impact of ASP pharmacist participation in microbiology rounds.

Methods

This was a single-center retrospective descriptive study including inpatient and ambulatory adults ( ≥18 years) with a susceptibility request requiring review during microbiology rounds between October 2018 and 3/2019. During daily microbiology rounds, susceptibility or workup requests were reviewed with the multidisciplinary microbiology team. The ASP pharmacist was called for their clinical expertise in assessing complicated or nonstandard susceptibility requests. Number and types of interventions made by ASP pharmacist were recorded (e.g., approval rate, education, ASP referral, ID consult referral). Additionally, number and types of intervention outcomes (unnecessary susceptibility prevented, optimized susceptibility request, treatment recommendation, improved clinician understanding, etc.) were analyzed.

Results

There were 66 susceptibility requests reviewed by an ASP pharmacist from October 2018 to 3/2019, of which 84.8% were inpatient. An ID provider was the requestor for 35% of requests. ASP pharmacists completed chart reviews for 92.4% of patients and contacted the requester/primary team 72.7% of the time. Thirty-three (50%) susceptibility requests were approved and, notably, 65.2% of requests from an ID provider were approved. Intervention rates for education provided, ASP referral, and ID consult referral were 50%, 1%, and 7%, respectively. ASP pharmacists were able to impact multiple intervention outcomes, including preventing unnecessary susceptibility requests (45.5%) and improving clinician understanding (39.4%) (Table 1).

Conclusion

ASP pharmacists are an important part of the microbiology team and are able to use their clinical expertise to help approve or deny susceptibility requests, make potential recommendations to optimize antimicrobial therapy, and provide education to other healthcare professionals.

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.

A Multicenter Stewardship Initiative to Decrease Excessive Duration of Antibiotic Therapy for the Treatment of Community-Acquired Pneumonia (CAP)

Background

Hospitals have implemented multifaceted approaches to quickly identify CAP, start timely therapy, and reduce hospital readmission, yet there has been minimal focus on providing appropriate duration of therapy. The IDSA CAP guidelines recommend 5 days of antibiotic therapy for patients that are clinically stable and quickly defervesce. However, previous publications suggest duration of therapy for CAP may be unnecessarily prolonged.

Methods

The objective of this multicenter, quasi-experimental study of hospitalized patients with CAP was to assess the impact of a prospective 6-month stewardship intervention on total duration of antibiotic therapy and associated clinical outcomes. All centers updated institutional CAP guidelines to promote IDSA-concordant durations of therapy and provided education to pharmacists and prescribers. Daily patient-specific prospective audit and feedback was provided by infectious diseases stewardship pharmacists to optimize compliance with guideline recommendations.

Results

A total of 600 patients were included (307 in the historic control group and 293 in the stewardship intervention group). The stewardship intervention led to significantly increased rates of compliance with IDSA duration of therapy recommendations (5.6% vs. 41.4%, P&lt; &lt; 0.01) and significantly reduced the duration of therapy for CAP (9 vs. 6 days, P &lt; 0.01). Inappropriate days of antibiotic therapy was reduced in the intervention group (4 vs. 1.6 days, P &lt; 0.01), and total avoidance of 720 excessive days of antibiotic therapy. Clinical outcomes, including mortality, length of hospitalization, readmission to hospital with pneumonia, presentation to the ER/clinic with pneumonia within 30 days of discharge, and incidence of C. difficilecolitis, were not different between groups.

Conclusion

This multicenter evaluation of a prospective stewardship intervention in hospitalized CAP patients reduced the total duration of antibiotic therapy and increased compliance with guideline-concordant duration of therapy without adversely affecting patient outcomes.

This project was funded through a competitive stewardship grant provided by Merck & Co.

Disclosures

A. Huang, Merck: Grant Investigator, Research grant; C. Nguyen, Merck: Grant Investigator, Research grant; J. Grieger, Merck: Grant Investigator, Research grant; S. Revolinski, Merck: Grant Investigator, Research grant; J. Li, Merck: Grant Investigator, Research grant; M. Mack, Merck: Grant Investigator, Research grant; J. N. Wainaina, Merck: Grant Investigator, Research grant; G. Eschenauer, Merck: Grant Investigator, Research grant; T. Patel, Merck: Grant Investigator, Research grant; V. Marshall, Merck: Grant Investigator, Research grant; J. Nagel, Merck: Grant Investigator, Research grant

A Single-center, Quasi-experimental Study to Evaluate the Impact of a Multiplex Polymerase Chain Reaction System Combined with Antimicrobial Stewardship Intervention on Time to Targeted Therapy in Patients with Suspected Central Nervous System Infection

Background

Empiric treatment for central nervous system (CNS) infections consists of coverage with multiple antimicrobial agents that may be continued until a pathogen can be identified. Identification may take significant time to result, leading to extended durations of multiple antimicrobial agents, delays in targeted therapy and subsequent adverse effects, such as nephrotoxicity and Clostridium difficile infection. A multiplex polymerase chain reaction (PCR) system that can identify 14 pathogens responsible for community-acquired CNS infections in 1 hour was recently FDA-approved for cerebrospinal fluid (CSF) analysis. The objective of this study was to determine the effect of this PCR paired with antimicrobial stewardship (AMS) team intervention on the time to targeted therapy.

Methods

During the intervention (Int) phase (January 25, 2017–April 30, 2017), all PCR results were called to the AMS team, who reviewed clinical data and provided antimicrobial recommendations per pre-determined protocol. Recommendations consisted of de-escalation or addition of therapy. The pre-intervention (PI) group consisted of patients with CSF culture obtained between January 25, 20116 and April 30, 2016.

Results

A total of 138 patients were evaluated; 46 in the Int group and 92 in the PI. Of the 46 patients in the Int group, 25 had a negative PCR result and were never initiated on antimicrobials. One patient required antimicrobial escalation. Twenty patients were started on empiric therapy and were candidates for de-escalation. In the PI group, there were no patients with CSF cultures that required therapy escalation, while 33 patients were initiated on empiric antimicrobials. Results from the subgroup of patients in whom empiric therapy was started as shown in Table 1.

Conclusion

Implementation of a multiplex PCR with AMS intervention resulted in decreased time to targeted therapy.

This project was funded through a competitive stewardship grant provided by Merck & Co.

Disclosures

S. Revolinski, Merck: Grant Investigator, Research grant; J. N. Wainaina, Merck: Grant Investigator, Research grant; A. Huang, Merck: Grant Investigator, Research grant