Treatment of Asymptomatic Bacteriuria after Implementation of an Inpatient Urine Culture Algorithm in the Electronic Medical Record

Ordering urine cultures in patients without pyuria is associated with the inappropriate treatment of asymptomatic bacteriuria (ASB). In 2015, our institution implemented recommendations based on practice guidelines for the management of ASB and revised the urine culture ordering process to limit cultures in immunocompetent patients without pyuria. The purpose of this study was to determine how the treatment of ASB has changed over time since altering the urine culture ordering process to reduce unnecessary cultures at an academic medical center. A quasi-experimental study was conducted for inpatients with urine cultures from January to March of 2014, 2015, 2016 and 2020. The primary outcome was the antibiotic treatment of asymptomatic bacteriuria for over 24 h. The secondary outcomes were the total days of antibiotic therapy, type of antibiotic prescribed and overall urine culture rates at the hospital. A total of 200 inpatients with ASB were included, 50 at random from each year. In both 2014 and 2015, 70% of the patients with ASB received antibiotic treatment. Antibiotics were prescribed to 68% and 54% of patients with ASB in 2016 and 2020, respectively. The average duration of therapy decreased from 5.12 days in 2014 to 3.46 days in 2020. Although the urine cultures were reduced, there was no immediate impact in the prescribing rates for patients with ASB after implementing this institutional guidance and an altered urine culture ordering process. Over time, there was an observed improvement in prescribing and the total days of antibiotic therapy. This could be attributed to increased familiarity with the guidelines, culture ordering practices or improved documentation. Based on these findings, additional provider education is needed to reinforce the guideline recommendations on the management of ASB.

Rapid and Sensitive Direct Detection and Identification of Poliovirus from Stool and Environmental Surveillance Samples by Use of Nanopore Sequencing

ABSTRACT Global poliovirus surveillance involves virus isolation from stool and environmental samples, intratypic differential (ITD) by PCR, and sequencing of the VP1 region to distinguish vaccine (Sabin), vaccine-derived, and wild-type polioviruses and to ensure an appropriate response. This cell culture algorithm takes 2 to 3 weeks on average between sample receipt and sequencing. Direct detection of viral RNA using PCR allows faster detection but has traditionally faced challenges related to poor sensitivity and difficulties in sequencing common samples containing poliovirus and enterovirus mixtures. We present a nested PCR and nanopore sequencing protocol that allows rapid (<3 days) and sensitive direct detection and sequencing of polioviruses in stool and environmental samples. We developed barcoded primers and a real-time analysis platform that generate accurate VP1 consensus sequences from multiplexed samples. The sensitivity and specificity of our protocol compared with those of cell culture were 90.9% (95% confidence interval, 75.7% to 98.1%) and 99.2% (95.5% to 100.0%) for wild-type 1 poliovirus, 92.5% (79.6% to 98.4%) and 98.7% (95.4% to 99.8%) for vaccine and vaccine-derived serotype 2 poliovirus, and 88.3% (81.2% to 93.5%) and 93.2% (88.6% to 96.3%) for Sabin 1 and 3 poliovirus alone or in mixtures when tested on 155 stool samples in Pakistan. Variant analysis of sequencing reads also allowed the identification of polioviruses and enteroviruses in artificial mixtures and was able to distinguish complex mixtures of polioviruses in environmental samples. The median identity of consensus nanopore sequences with Sanger or Illumina sequences from the same samples was >99.9%. This novel method shows promise as a faster and safer alternative to cell culture for the detection and real-time sequencing of polioviruses in stool and environmental samples.

An integrated model for maintenance policies and production scheduling based on immune–culture algorithm

The development of integrated modelling for maintenance policies of multi-component repairable system and production scheduling is challenging for two reasons. First, capturing dependency of this multi-component repairable system is difficult because different failure types associated with different components are under competing risks and their complicated relationships may lead to overall system dependency. Second, the integrated model is difficult to optimize because it is an NP-hard problem that exact optimization methods are intractable. For coping with these two difficulties, we propose a parametric statistical model using copula function to capture the overall system dependency. Under partially perfect maintenance policy at component-level, the likelihood functions for observed failures are derived and maximum likelihood method is used to estimate unknown parameters. Then relying on this parametric statistical model, the system hazard function is derived to depict the reliability-based imperfect preventive maintenance policy at system-level. Finally, to obtain the optimal solution(s) of the integrated model, we design an adaptive immune clone selection–culture algorithm, which is inspired from immune clone selection algorithm and culture algorithm. Results of the case study validate that our proposed maintenance policies and methodology have great advantages over the component-level or system-level maintenance policy and immune clone selection algorithm.

Rapid and sensitive direct detection and identification of poliovirus from stool and environmental surveillance samples using nanopore sequencing

Global poliovirus surveillance involves virus isolation from stool and environmental samples, intratypic differential (ITD) by PCR and sequencing of the VP1 region to distinguish vaccine (Sabin), vaccine-derived and wild-type polioviruses and ensure an appropriate response. This cell-culture algorithm takes 2-3 weeks on average between sample receipt and sequencing. Direct detection of viral RNA using PCR allows faster detection but has traditionally faced challenges related to poor sensitivity and difficulties in sequencing common samples containing poliovirus and enterovirus mixtures. We present a nested PCR and nanopore sequencing protocol that allows rapid (<3 days) and sensitive direct detection and sequencing of polioviruses in stool and environmental samples. We developed barcoded primers and a real-time analysis platform that generate accurate VP1 consensus sequences from multiplexed samples. The sensitivity and specificity compared with cell-culture were 90.9% (95% Confidence Interval: 75.7-98.1%) and 99.2% (95.5-100.0%) for wild-type 1 poliovirus, 92.5% (79.6-98.4%) and 98.7% (95.4-99.8%) for vaccine and vaccine-derived serotype 2 poliovirus, and 88.3% (81.2-93.5%) and 93.2% (88.6-96.3%) for Sabin 1 and 3 poliovirus alone or in mixtures when tested on 155 stool samples in Pakistan. Variant analysis of sequencing reads also allowed identification of polioviruses and enteroviruses in artificial mixtures and was able to distinguish complex mixtures of polioviruses in environmental samples. The median identity of consensus nanopore sequences with Sanger or Illumina sequences from the same samples was >99.9%. This novel method shows promise as a faster and safer alternative to cell-culture for the detection and real-time sequencing of polioviruses in stool and environmental samples.

1112. Improving Urine Culturing Practices in a Neurocritical Care Unit through a Multidisciplinary Algorithm-Based Approach

Background Asymptomatic bacteriuria is common in hospitalized patients with urinary catheters. Inappropriate urine culturing as part of reflexive response to fever contributes to unnecessary and excessive antibiotic use, selection for resistant organisms, increased risk for Clostridium difficile infections, and false elevation in catheter-associated urinary tract infection (CAUTI) rates. This project aimed to implement an evidence-based urine culture algorithm in a 33-bed neurocritical care unit, a unit with a historically elevated CAUTI rate due to a high prevalence of noninfectious fever. Methods A multidisciplinary quality improvement project was initiated in August 2018 by the Infection Prevention, Quality and Safety, Neurocritical Care, Trauma, and Neurosurgery teams of an urban academic health center. The group implemented a urine culture algorithm that was adapted from the Infectious Diseases Society of America (IDSA) guidelines that clearly highlighted appropriate indications for sending urine cultures. The team agreed to utilize a urinalysis with reflex to culture as the preferred method to evaluate for CAUTI. The algorithm was implemented in September 2018. Outcomes were compared for pre-implementation (March-August 2018) and post-implementation (September 2018–February 2019). Results The NHSN CAUTI rate decreased from 4.52/1,000 Foley days to 1.27/1,000 Foley days (P-value 0.037) as a result of the intervention. The number of urine cultures ordered decreased by 82% after implementation. No cases of bacteremia or mortality secondary to a urinary source were identified during the project. Total days of antibiotic therapy for the unit was similar between the pre- and post-implementation time periods (P = 0.631). Conclusion Implementation of a urine culture algorithm in a neurocritical care unit resulted in reduced CAUTI rate with less financial and operational waste in unnecessary orders and treatment, without resulting in adverse events to patients as a result of missed diagnosis. Disclosures All authors: No reported disclosures.

MANAGEMENT OF ENERGY EFFICIENT PRODUCTION OF INULINASE ASPERGILLUS AWAMORI 2250

Цель работы – повышение точности и надежности управления процессом производства биомассы аэробных микроорганизмов, снижение удельных энергозатрат и повышение выхода готовой культуры. Разработан алгоритм управления процессом производства биомассы аэробных микроорганизмов. В качестве объекта производства использован ферментный препарат инулиназа, полученный глубинным способом с использованием продуцента грибов Aspergillus awamori 2250. Процесс культивирования осуществлялся в вертикальном ферментере серии Biostat (Sartorius Stedim Biotech GmbH, Германия) с рабочим объемом 100 л, предназначенным для выращивания микроорганизмов глубинным способом. Для стабилизации температурных режимов культивирования в инокуляторе, непосредственном выращивании микроорганизмов в ферментере и охлаждении готовой культуры в приемных сборниках осуществляли подготовку теплой и холодной воды с использованием пароэжекторной холодильной машины, работающей в режиме теплового насоса. Алгоритм управления производства биомассы микроорганизмов Aspergillus awamori 2250 позволил обеспечить стабилизацию параметров в области оптимальных значений и увеличить выход готовой культуры; предотвратить выброс отработанных теплоносителей в окружающую среду; обеспечить существенную экономию теплоэнергетических затрат за счет рекуперации и утилизации отработанных энергоносителей в замкнутых термодинамических циклах по материальным и энергетическим потокам. The work purpose – increase in accuracy and reliability of management of process of production of biomass of aerobic microorganisms, decrease in specific energy consumption and increase in an exit of ready culture. Algorithm of process of production of biomass of aerobic microorganisms is developed. Process of cultivation was carried out in a vertical fermenter of Sartorius Stedim Biotech of the Biostat series with the working volume of 100 liters intended for cultivation of microorganisms. For stabilization of temperature conditions of cultivation in an inokulyator, direct cultivation of culture of microorganisms in a fermenter and cooling of ready culture in reception collections carried out preparation of warm and cold water with use of the paroezhektorny refrigerator working in the thermal pump mode. The control algorithm of production of biomass of microorganisms of Aspergillus awamori 2250 has allowed to provide stabilization of parameters in the field of optimum values and to increase an exit of ready culture; to prevent emission of the fulfilled heat carriers in the environment; to provide essential economy of heat power expenses due to recovery and utilization of the fulfilled energy carriers in the closed thermodynamic cycles on material and power streams.