Multiplex Respiratory Virus Testing for Antimicrobial Stewardship: A Prospective Assessment of Antimicrobial Use and Clinical Outcomes Among Hospitalized Adults

What Is Left to Tackle in Inpatient Antimicrobial Stewardship Practice and Research

Despite widespread uptake of antimicrobial stewardship in acute care hospitals, there is ongoing need for innovation and optimization of ASPs. This article discusses current antimicrobial stewardship practice challenges and ways to improve current antimicrobial stewardship workflows. Additionally, we propose new workflows that further engage front line clinicians in optimizing their own antibiotic decision making.

Evaluation of appropriate transmission-based precautions for non-SARS-CoV-2 respiratory viruses

Appropriateness of transmission-based precautions after positive result for a non-SARS-CoV-2 virus was evaluated. Most patients (77.2%) lacked appropriate precautions within 3 hours of virus detection; 36.9% remained without appropriate precautions during their stay. With recent cessation of universal masking, adherence to infection control best practices is needed to optimize safety.

Real-life impact of respiratory panel PCR assay on antibiotic prescription in geriatric acute care in the pre-COVID-19 era

OBJECTIVES

In this era of bacterial resistance, avoiding inappropriate use of antibiotic treatments is of major importance. Respiratory tract infections are frequent among older patients, and differentiating viral from bacterial infections is a challenge. The aim of our study was to evaluate the impact of recently available respiratory PCR testing on antimicrobial prescription in geriatric acute care.

METHODS

We performed a retrospective study, including all hospitalized geriatric patients who had had multiplex respiratory PCR testing prescribed from 1st October 2018 to 30th September 2019. The PCR test comprised a respiratory viral panel (RVP) and a respiratory bacterial panel (RBP). PCR testing could be prescribed at any time during hospitalization by geriatricians. Our primary endpoint was antibiotic prescription after viral multiplex PCR testing results.

RESULTS

All in all, 193 patients were included, 88 (45.6%) of whom had positive RVP, while none had positive RBP. Patients with positive RVP had significantly fewer antibiotic prescriptions following test results than patients with negative RVP (odds ratio (OR) 0.41, 95% confidence interval (CI) 0.22-0.77; p = 0.004). Among positive-RVP patients, factors associated with antibiotic continuation were presence of radiological infiltrate (OR 12.02, 95%CI 3.07-30.29), and detected Respiratory Syncytial Virus (OR 7.54, 95%CI 1.74-32.65). That said, discontinuation of antibiotic treatment seems safe.

CONCLUSION

In this population, the impact of viral detection by respiratory multiplex PCR on antibiotic therapy was low. It could be optimized by means of clearly formulated local guidelines, qualified staff and specific training by infectious disease specialists. Cost-effectiveness studies are necessary.

Reducing antimicrobial overuse through targeted therapy for patients with community-acquired pneumonia: a study protocol for a cluster-randomized factorial controlled trial (CARE-CAP)

BACKGROUND

Community-acquired pneumonia (CAP) is a significant public health concern and a leading cause of hospitalization and inpatient antimicrobial use in the USA. However, determining the etiologic pathogen is challenging because traditional culture methods are slow and insensitive, leading to prolonged empiric therapy with extended-spectrum antibiotics (ESA) that contributes to increased hospital length of stay, and antimicrobial resistance. Two potential ways to reduce the exposure to ESA are (a) rapid diagnostic assays that can provide accurate results within hours, obviating the need for empiric therapy, and (b) de-escalation following negative bacterial cultures in clinically stable patients.

METHODS

We will conduct a large pragmatic 2 × 2 factorial cluster-randomized controlled trial across 12 hospitals in the Cleveland Clinic Health System that will test these two approaches to reducing the use of ESA in adult patients (age ≥ 18 years) with CAP. We will enroll over 12,000 patients and evaluate the independent and combined effects of routine use of rapid diagnostic testing at admission and pharmacist-led de-escalation after 48 h for clinically stable patients with negative cultures vs usual care. We hypothesize that both approaches will reduce days on ESA. Our primary outcome is the duration of exposure to ESA therapy, a key driver of antimicrobial resistance. Secondary outcomes include detection of respiratory viruses, treatment with anti-viral medications, positive pneumococcal urinary antigen test, de-escalation by 72 h from admission, re-escalation to ESA after de-escalation, total duration of any antibiotic, 14-day in-hospital mortality, intensive care unit transfer after admission, healthcare-associated C. difficile infection, acute kidney injury, total inpatient cost, and hospital length-of-stay.

DISCUSSION

Our study aims to determine whether identifying an etiological agent early and pharmacist-led de-escalation (calling attention to negative cultures) can safely reduce the use of ESA in patients with CAP. If successful, our findings should lead to better antimicrobial stewardship, as well as improved patient outcomes and reduced healthcare costs. Our findings may also inform clinical guidelines on the optimal management of CAP.

TRIAL REGISTRATION

ClinicalTrials.gov NCT05568654 . Registered on October 4, 2022.

The effect of Telehealth Antimicrobial Stewardship Program (Tele-ASP) on antimicrobial use in a pediatric intensive care unit: Pre- and post-implementation single center study

BACKGROUND

Overuse or misuse of antimicrobials is common in pediatric intensive care units (PICU) and may be associated with poor clinical outcomes. Although an antimicrobial stewardship program (ASP) has been found to improve this practice, the required expertise in infectious diseases may be limited in some centers. We aimed to evaluate the effect of telehealth ASP on the rate of PICU antimicrobial use in a center without a local Infectious Diseases consultation service.

METHODS

A retrospective cohort study was performed between October 1st, 2018, and October 31st, 2020, in Farwaniya Hospital PICU, a 20-bed unit. All pediatric patients who were admitted to PICU and received systemic antimicrobials during the study period were included and followed until hospital discharge. The ASP team provided weekly prospective audit and feedback on antimicrobial use starting October 8th, 2019. A pediatric infectious diseases specialist joined the ASP rounds remotely. Descriptive analyses and a pre-post intervention comparison of days of therapy (DOT) were used to assess the effectiveness of the ASP intervention.

RESULTS

There were 272 and 156 PICU admissions received systemic antimicrobial before and after the initiation of ASP, respectively. Bronchiolitis and pneumonia were the most common admission diagnoses, together compromising 60.7% and 61.2% of cases pre- and post-ASP. The requirement for respiratory support was higher post-ASP (76.5% vs. 91.5%, p < 0.001). Average monthly antimicrobial use decreased from 922 (95%CI 745-1000) to 485 DOT/1000 patient-days (95%CI 246-722, P < 0.05). A decline in DOT was observed across most antibiotic classes, except for ceftriaxone. No effect on the length of PICU stay, length of hospitalization, or mortality was observed. Most (89.7%) ASP recommendations were followed either fully or partially.

CONCLUSION

In settings where Infectious Diseases consultation services are unavailable, PICU telehealth ASP can be effectively implemented and associated with significantly reducing antimicrobial use.

Enhancing antimicrobial surveillance in hospitals in England: a RAND-modified Delphi

Background

Optimizing antimicrobial use (AMU) is key to reducing antimicrobial-resistant infections, but current AMU monitoring in hospital provides limited insights for quality improvement.

Objectives

To understand stakeholders’ priorities for developing national AMU surveillance in English hospitals to serve the needs of national policy makers and front-line practitioners.

Methods

Characteristics of existing AMU surveillance systems were identified from a previous systematic review and categorized by the Acceptability, Practicability, Effectiveness, Affordability, Side-effects and Equity (APEASE) criteria. Stakeholders prioritized characteristics using a two-round RAND-modified Delphi (rating round 1, telephone panel discussion, rating round 2). Findings informed the design of a framework used to assess the extent to which existing surveillance approaches meet stakeholders’ needs.

Results

Between 17/09/19 and 01/11/19, 24 stakeholders with national and local roles related to AMU prioritized 23 characteristics of AMU surveillance describing: resource for surveillance, data collection, data availability and pathways to translate information from surveillance into practice. No existing surveillance approaches demonstrated all prioritized characteristics. The most common limitation was failure to facilitate clinician engagement with AMU through delays in data access and/or limited availability of disaggregated metrics of prescribing.

Conclusions

Current surveillance delivers national public health priorities but improving stewardship demands patient-level data linked to clinical outcomes. This study offers a framework to develop current surveillance to meet the needs of local stakeholders in England. Increased investment in data infrastructure and training is essential to make information held within electronic systems available to front-line clinicians to facilitate quality improvement.

Outpatient Antibiotic and Antiviral Utilization Patterns in Patients Tested for Respiratory Pathogens in the United States: A Real-World Database Study

This retrospective observational study evaluated outpatient treatment patterns among patients with molecular-based viral diagnostic testing for suspected upper respiratory tract infections in the United States. Patients with a respiratory viral test were identified from 1 August 2016 to 1 July 2019 in a large national reference laboratory database linked to IQVIA’s prescription and medical claims databases. Antibiotic and influenza antiviral treatment patterns were reported up to 7 days post-test result. Predictors of antibiotic utilization were assessed using multivariable logistic regression. Among 9561 patients included in the study, 24.6% had evidence of ≥1 filled antibiotic prescription. Antibiotic utilization was higher in patients who tested negative for all viral targets (odds ratio [OR], 1.33; 95% confidence interval [CI], 1.17–1.50) and patients positive for non-influenza viruses (OR, 1.28; 95% CI, 1.09–1.51) compared with those influenza-positive only. Age ≥ 50 years and location outside of the northeast United States also predicted antibiotic utilization. Influenza antivirals were more common in influenza-positive patients compared with patients with other test results (32.5% vs. 3.6–9.0%). Thus, in this real-world study, antibiotic utilization was elevated in patients positive for non-influenza viruses, although antibiotics would generally not be indicated. Further research on pairing diagnostic tools with outpatient antibiotic stewardship programs is needed.

New testing guidelines for community-acquired pneumonia

PURPOSE OF REVIEW

The purpose of this article is to review diagnostic testing recommendations outlined in the current American Thoracic Society (ATS)/Infectious Diseases Society of America (IDSA) community-acquired pneumonia (CAP) guideline and the 2021 ATS guideline for noninfluenza respiratory viruses.

RECENT FINDINGS

Diagnostic testing in CAP with gram stain, lower respiratory and blood cultures, Streptococcal and Legionella urinary antigens are not routinely recommended unless identified as severe CAP or with risk factors for Methicillin-resistant Staphylococcus aureus (MRSA) or Pseudomonas aeruginosa infection. Influenza virus testing remains a strong recommendation during periods of community viral spread.An additional 2021 ATS clinical practice guideline reviewed the use of molecular testing for noninfluenza viral pathogens in adults with suspected CAP and recommended testing in those hospitalized with severe CAP and/or various immunocompromising conditions.

SUMMARY

Diagnostic testing remains an important component of confirming and treating CAP. The CAP guideline includes recommendations surrounding diagnostic testing with lower respiratory gram stain and culture, blood cultures, Legionella and Pneumococcal urinary antigen, influenza viral testing and serum procalcitonin.There is a strong recommendation to obtain influenza virus testing during periods of community spread. However, the use of other diagnostics such as gram stain, lower respiratory and blood culture, and urinary antigen testing are dependent on severity of illness and whether a patient has been identified as having strong risk factors for MRSA or P. aeruginosa infection. The 2021 ATS clinical practice document did not routinely recommend testing noninfluenza respiratory viruses unless identified as having severe CAP and/or various immunocompromising conditions.

Viral co-infections are associated with increased rates of hospitalization in those with influenza

Background

Influenza causes significant morbidity and mortality in the United States. Among patients infected with influenza, the presence of bacterial co‐infection is associated with worse clinical outcomes; less is known regarding the clinical importance of viral co‐infections. The objective of this study was to determine rates of viral co‐infections in emergency department (ED) patients with confirmed influenza and association of co‐infection with disease severity.

Methods

Secondary analysis of a biorepository and clinical database from a parent study where rapid influenza testing was implemented in four U.S. academic EDs, during the 2014–2015 influenza season. Patients were systematically tested for influenza virus using a validated clinical decision guideline. Demographic and clinical data were extracted from medical records; nasopharyngeal specimens from influenza‐positive patients were tested for viral co‐infections (ePlex, Genmark Diagnostics). Patterns of viral co‐infections were evaluated using chi‐square analysis. The association of viral co‐infection with hospital admission was assessed using univariate and multivariate regression.

Results

The overall influenza A/B positivity rate was 18.1% (1071/5919). Of the 999 samples with ePlex results, the prevalence of viral co‐infections was 7.9% (79/999). The most common viral co‐infection was rhinovirus/enterovirus (RhV/EV), at 3.9% (39/999). The odds of hospital admission (OR 2.33, 95% CI: 1.01–5.34) increased significantly for those with viral co‐infections (other than RhV/EV) versus those with influenza A infection only.

Conclusion

Presence of viral co‐infection (other than RhV/EV) in ED influenza A/B positive patients was independently associated with increased risk of hospital admission. Further research is needed to determine clinical utility of ED multiplex testing.

In-Hospital Macro-, Meso-, and Micro-Drivers and Interventions for Antibiotic Use and Resistance: A Rapid Evidence Synthesis of Data from Canada and Other OECD Countries

Hospitals continue to face challenges in reducing incorrect antibiotic use due to social and cultural factors at the level of the health system, the care facility, the provider, and the patient. The objective of this paper is to highlight the social and cultural drivers of antimicrobial use and resistance and targeted interventions for secondary and tertiary care settings in Canada and other OECD countries. This paper is an extension of the synthesis conducted for the Public Health Agency of Canada's 2019 Spotlight Report: Preserving Antibiotics Now and Into the Future. We conducted a systematic review with a few modifications to meet rapid timelines. We conducted a search in Ovid MEDLINE and McMaster University's evidence databases for systematic reviews and then for individual Canadian studies. To cast a wider net, we searched OECD organization websites and screened reference lists from systematic reviews. We synthesized the evidence narratively and categorized the evidence into macro-, meso-, and microlevel. A total of 70 studies were (a) from OCED countries and summarized evidence of potential sociocultural antimicrobial resistance and use barriers or facilitators and/or interventions addressing these challenges; (b) systematic reviews with 50% of included studies that are situated in secondary and tertiary settings; and (c) published in Canada's two official languages, English and French. We found that hospital structures and policies may influence antibiotic utilization and variations in antimicrobial management. Microlevel factors may sway inappropriate prescribing among clinicians. The amount and type of antibiotics used may affect resistance rates. Interventions were mainly comprised of antibiotic stewardship and training that modify clinician behavior and that educate patients and carers. This evidence synthesis illustrates the various drivers of, and interventions for, antimicrobial use and resistance at the macro-, meso-, and microlevel in secondary and tertiary settings. We demonstrate that upstream drivers may lead to downstream events that influence antimicrobial resistance.

The long-term prognostic value of serum 25(OH)D, albumin, and LL-37 levels in acute respiratory diseases among older adults

Background

Older adults are more susceptible to respiratory tract infection than healthy working age adults. The increased susceptibility of older adults is thought to be interlinked with vitamin D status, nourishment, and immunological state in general. Data are scarce whether these parameters could serve as prognostic markers.

Aim

To study whether serum 25(OH)D, albumin, and LL-37 level could give prognostic value of long-term survival in the older adults with multimorbidity and acute respiratory infection.

Methods

Consecutive episodes of hospital care of patients 65 years and older with respiratory symptoms were prospectively studied as a cohort. Standard clinical questionnaire was filled by the study physician. Laboratory markers included serum levels of 25(OH)D, albumin and LL-37, C-reactive protein (CRP), white blood cell count (WBC) and polymerase chain reaction diagnostics for 14 respiratory viruses. Pneumonia was confirmed by chest radiographs. Respiratory illness severity, death at ward, length of hospital stays, and 5-year survival were used as outcomes.

Results

In total, 289 older adult patients with mean age of 83 years were included in the study. Serum 25(OH)D deficiency (< 50 nmol/liter) was present in 59% and hypoalbuminemia (< 3.5 g/dL) in 55% of the study patients. Low serum albumin level was associated to one, two- and five-year mortality after hospital stay (all P < .05). In addition, it was associated with pneumonia, dyspnea, over 13-night long stay at ward and death at ward (all P < .05). No associations were seen between serum 25(OH)D and LL-37 levels and disease severity, short-term clinical outcome, or long-term survival. Associations between serum 25(OH)D, albumin, and LL-37 levels and respiratory virus presence were not seen.

Conclusions

Serum albumin level on admission seems to give valuable information about the patients’ general health and recovery potential in treating older adults with respiratory symptoms. Serum 25(OH)D and LL-37 had no associations with disease severity or long- and short-term prognosis among older adults hospitalized with respiratory symptoms.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12877-022-02836-8.

Approach to fever in patients with neutropenia: a review of diagnosis and management

Febrile neutropenia (FN) is associated with mortality rates as high as 40%, highlighting the importance of appropriate clinical management in this patient population. The morbidity and mortality of FN can be attributed largely to infectious processes, with specific concern for infections caused by pathogens with antimicrobial resistance. Expeditious identification of responsible pathogens and subsequent initiation of empiric antimicrobial therapy is imperative. There are four commonly used guidelines, which have variable recommendations for empiric therapy in these populations. All agree that changes could be made once patients are stable and/or with an absolute neutrophil count (ANC) over 500 cells/mcL. Diagnostic advances have the potential to improve knowledge of pathogens responsible for FN and decrease time to results. In addition, more recent data show that rapid de-escalation or discontinuation of empiric therapy, regardless of ANC, may reduce days of therapy, adverse effects, and cost, without affecting clinical outcomes. Antimicrobial and diagnostic stewardship should be performed to identify, utilize, and respond to appropriate rapid diagnostic tests that will aid in the definitive management of this population.

Impact of multiplexed respiratory viral panels on infection control measures and antimicrobial stewardship: a review of the literature

Multiplexed respiratory viral panels (MRVP) have recently been added to the diagnostic work-up of respiratory infections. This review provides a summary of the main literature of MRVP for patients with regard to 3 different topics. Can the results of MRVP reduce the inappropriate use of antibiotics, can they guide the use of appropriate antiviral therapy and do they have an added value with respect to infection control measures? Literature was searched for based on a defined search string using both the PubMed and Embase database. Twenty-five articles report on the impact of MRVP on antibiotic therapy. In all the articles where active antimicrobial stewardship was performed (e.g., education/advice on interpreting results of MRVP) (N = 9), a reduction in antibiotic therapy was shown (with exception of 2 studies). Three studies evaluating the effect of MRVP on antimicrobial use in a population that is not suspected of having bacterial pneumonia (e.g., absence of radiology suggestive for bacterial infection or low PCT) found a positive impact on antibiotic therapy. Eight studies with a short TAT (< 7 h) had a positive impact on use of antibiotic therapy. Eleven studies focused on the impact of MRVP on antiviral use. In contrast to antibiotic reduction, all studies systematically objectified improved antiviral use as a consequence of MRVP results. With regard to the impact of MRVP on infection control, eleven articles were withheld. All these studies led to a more accurate use of infection control measures by detecting unidentified pathogens or stopping isolation precautions in case of a negative MRVP result. MRVP don’t reduce antibiotic therapy in all populations. Reduction seems more likely if the following factors are present: active antimicrobial stewardship, low likelihood of a bacterial infection, and a short turnaround time to result. With respect to antiviral therapy, all studies have an impact but the targeted use of antivirals is so far not that evidence based for all viral respiratory pathogens. Regarding infection control measures, the potential impact of MRVP is high because of the need of additional isolation precautions for many respiratory viruses, although logistical problems can occur.

Nucleic Acid-based Testing for Noninfluenza Viral Pathogens in Adults with Suspected Community-acquired Pneumonia. An Official American Thoracic Society Clinical Practice Guideline

Background: This document provides evidence-based clinical practice guidelines on the diagnostic utility of nucleic acid–based testing of respiratory samples for viral pathogens other than influenza in adults with suspected community-acquired pneumonia (CAP).

Methods: A multidisciplinary panel developed a Population–Intervention–Comparison–Outcome question, conducted a pragmatic systematic review, and applied Grading of Recommendations, Assessment, Development, and Evaluation methodology for clinical recommendations.

Results: The panel evaluated the literature to develop recommendations regarding whether routine diagnostics should include nucleic acid–based testing of respiratory samples for viral pathogens other than influenza in suspected CAP. The evidence addressing this topic was generally adjudicated to be of very low quality because of risk of bias and imprecision. Furthermore, there was little direct evidence supporting a role for routine nucleic acid–based testing of respiratory samples in improving critical outcomes such as overall survival or antibiotic use patterns. However, on the basis of direct and indirect evidence, recommendations were made for both outpatient and hospitalized patients with suspected CAP. Testing for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection was not addressed in the literature at the time of the evidence review.

Conclusions: The panel formulated and provided their rationale for recommendations on nucleic acid–based diagnostics for viral pathogens other than influenza for patients with suspected CAP.

An evaluation of the Unyvero pneumonia system for rapid detection of microorganisms and resistance markers of lower respiratory infections-a multicenter prospective study on ICU patients

Rapid diagnosis of microorganisms and antibiotic resistance is vital for the appropriate treatment of patients with lower respiratory infections, especially for patients in Intensive Care Unit. We conducted a multicenter prospective study to evaluate the ability of the Unyvero pneumonia system for rapid detection from bronchoalveolar lavage fluid (BALF) in China. Eighty-four patients with lower respiratory infections were enrolled, and their BALF samples were collected, and Unyvero, a rapid molecular diagnostic sample-to-answer solution based on multiple PCRs, was applied to detect 21 types of pathogens and 19 types of resistance markers, compared to a routine bacterial culture method. The overall concordance of Unyvero and routine culture was 69/84 (82.1%). Unyvero detected more microorganisms than routine culture (38.1% vs 27.4%, P<0.05) and reported multi-pathogens in more patients than routine culture (10.7% vs 2.4%, P=0.01). The overall sensitivity and specificity of Unyvero for bacteria detection were 84.0% and 98.0%. Besides, Unyvero showed a good performance for antibiotic-resistant bacteria, except Pseudomonas aeruginosa. The concordance was 87.5-100% for methicillin-resistant Staphylococcus aureus and carbapenem-resistant isolates but was only 20-33.3% for Pseudomonas aeruginosa. The high-level semi-quantitative signal intensity of microorganisms detected positive by Unyvero correlates well with positive bacterial cultures. For specimens that were exposed to antibiotic treatment, the Unyvero pneumonia system showed a high concordance with routine bacterial culture and performs well for the detection of antibiotic-resistant bacteria, especially, carbapenem-resistant Klebsiella pneumoniae. It shows promise in guiding the clinical use of antibiotics, such as ceftazidime/avibactam. However, the system needs improvement in detecting resistance markers of Pseudomonas aeruginosa.

Propolis antiviral and immunomodulatory activity: a review and perspectives for COVID-19 treatment

OBJECTIVES

Viral outbreaks are a frequent concern for humans. A great variety of drugs has been used to treat viral diseases, which are not always safe and effective and may induce adverse effects, indicating the need for new antiviral drugs extracted from natural sources. Propolis is a bee-made product exhibiting many biological properties. An overview of viruses, antiviral immunity, propolis safety and its immunomodulatory and antiviral action is reported, as well as perspectives for coronavirus disease 2019 (COVID-19) treatment. PubMed platform was used for data collection, searching for the keywords "propolis", "virus", "antiviral", "antimicrobial" and "coronavirus".

KEY FINDINGS

Propolis is safe and exerts antiviral and immunomodulatory activity; however, clinical trials should investigate its effects on individuals with viral diseases, in combination or not with antiviral drugs or vaccines.

SUMMARY

Regarding COVID-19, the effects of propolis should be investigated directly on the virus in vitro or on infected individuals alone or in combination with antiviral drugs, due to its immunomodulatory and anti-inflammatory action. Propolis administration simultaneously with vaccines should be analyzed, due to its adjuvant properties, to enhance the individuals' immune response. The search for therapeutic targets may be useful to find out how propolis can help to control COVID-19.

Point-of-care testing for influenza in a university emergency department: A prospective study

BACKGROUND

Seasonal influenza is a burden for emergency departments (ED). The aim of this study was to investigate whether point-of-care (POC) PCR testing can be used to reduce staff sick days and improve diagnostic and therapeutic procedures.

OBJECTIVES

The aim of this study was to investigate whether point-of-care (POC) PCR testing can be used to reduce staff sick days and improve diagnostic and therapeutic procedures.

METHODS

Using a cross-over design, the cobas® Liat® Influenza A/B POC PCR test (Liat) was compared with standard clinical practice during the 2019/2020 influenza season. All adult patients (aged ≥ 18 years) with fever (≥38°C) and respiratory symptoms were included. Primary end points were the prevalence of influenza infections in the ED and staff sick days. Secondary end points were frequency of antiviral and antibacterial therapy, time between admission and test result or treatment initiation, patient disposition, ED length of stay (LOS), and for inpatients mortality and LOS. Nurses were interviewed about handling and integration of POC testing. The occurrence of SARS-CoV-2 infections coincided with the second half of the study.

RESULTS

A total of 828 patients were enrolled in the study. All 375 patients of the intervention group were tested with Liat, and 103 patients of them (27.6%) tested positive. During the intervention period, staff sick days were reduced by 34.4% (P = .023). Significantly, more patients in the intervention group received antiviral therapy with neuraminidase inhibitors (7.2% vs 3.8%, P = .028) and tested patients received antibiotics more frequently (40.0% vs 31.6%, P = .033). Patients with POC test were transferred to external hospitals significantly more often (5.6% vs 1.3%, P = .01).

CONCLUSION

We conclude that POC testing for influenza is useful in the ED, especially if it is heavily frequented by patients with respiratory symptoms.

Clinical Characteristics and Outcomes of Severe Pneumonia in Children Under 5 Years Old With and Without Adenovirus Infection in Guangzhou

Objectives: To identify the differences of clinical characteristics and outcomes of severe pneumonia in children under 5 years old with and without adenovirus infection. Methods: A retrospective cohort study was conducted in three pediatric hospitals in Guangzhou, China. In total, 1,595 children under the age of 5 with WHO-defined severe pneumonia had adenovirus testing performed between January 1, 2009 and December 31, 2019. Demographics, complications, the first routine laboratory findings, therapeutic records, and clinical outcome were collected from electronic medical records. We compared characteristics of children with and without adenovirus infection. Results: Adenovirus was detected in 75 (4.7%) out of 1,595 children with severe pneumonia. Cases with adenovirus infection were more likely to be boys (74.7 vs. 63.0%), older than 1 year old (78.7 vs. 25.1%), but less likely to have mixed virus infections (25.3 vs. 92.9%) and combined with cardiovascular disease (12.0 vs. 39.7%), and had more abnormal laboratory results than cases without adenovirus infection. Antiviral therapy (4.9%) was rarely used in children with severe pneumonia, but antibiotic therapy (65.3%) was commonly used, especially in cases with adenovirus infection (91.9%). Children infected with adenovirus (9.3 vs. 2.5%) were also hospitalized longer and had a higher mortality within 30 days of hospitalization. Conclusions: Children with severe pneumonia under 5 years old with adenovirus infection had more abnormal laboratory findings and more severe clinical outcomes than cases without adenovirus infection. More attention should be focused on the harm caused by adenovirus infection.

Molecular Testing for Acute Respiratory Tract Infections: Clinical and Diagnostic Recommendations From the IDSA's Diagnostics Committee

The clinical signs and symptoms of acute respiratory tract infections (RTIs) are not pathogen specific. Highly sensitive and specific nucleic acid amplification tests have become the diagnostic reference standard for viruses, and translation of bacterial assays from basic research to routine clinical practice represents an exciting advance in respiratory medicine. Most recently, molecular diagnostics have played an essential role in the global health response to the novel coronavirus pandemic. How best to use newer molecular tests for RTI in combination with clinical judgment and traditional methods can be bewildering given the plethora of available assays and rapidly evolving technologies. Here, we summarize the current state of the art with respect to the diagnosis of viral and bacterial RTIs, provide a practical framework for diagnostic decision making using selected patient-centered vignettes, and make recommendations for future studies to advance the field.

Utility of the respiratory viral panel as an antimicrobial stewardship tool

WHAT IS KNOWN AND OBJECTIVE

The development of rapid diagnostics has revolutionized antimicrobial stewardship with efforts targeting earlier de-escalation or discontinuation of antibiotics. The respiratory viral panel (RVP) is one tool quickly able to detect common viral and bacterial pathogens using polymerase chain reaction technology. Utility may be further enhanced in conjunction with procalcitonin (PCT). However, the optimal use of the RVP to the clinical pharmacist in the treatment of community-acquired respiratory infections remains unclear.

METHODS

The purpose of this guide is to review the available literature regarding the impact of the RVP with and without procalcitonin on antimicrobial stewardship efforts and to provide guidance on how to use each of these tools.

RESULTS AND DISCUSSION

In total, 13 studies were included, 5 of which utilized PCT in conjunction with RVP and 8 of which did not use PCT. The majority of studies were retrospective in nature, and the most common outcomes evaluated were antibiotic days of therapy (DOT) and time to antibiotic discontinuation.

WHAT IS NEW AND CONCLUSION

After review, RVP alone has limited value to antimicrobial stewardship; however, when used in conjunction with procalcitonin, RVP has the potential to reduce antibiotic use and duration.

Antimicrobial Stewardship Optimization in the Emergency Department: The Effect of Multiplex Respiratory Pathogen Testing and Targeted Educational Intervention

Background

Antibacterial agents are often prescribed for patients with suspected respiratory tract infections even though these are most often caused by viruses. In this study, we sought to evaluate the effect of Respiratory Pathogen Panel (RPP) PCR result availability and antimicrobial stewardship education on antibiotic prescription rates in the adult emergency department (ED).

Methods

We compared rates of antibacterial and oseltamivir prescriptions between 2 nonconsecutive influenza seasons among ED visits, wherein the latter season followed the implementation of a comprehensive educational stewardship campaign. In addition, we sought to elucidate the effect of RPP-PCR on antibiotic prescriptions, with focus on result availability prior to the conclusion of emergency department encounters.

Results

Antibiotic prescription rates globally decreased by 17.9% in the FS-17/18 cohort compared to FS-14/15 (P &lt; 0.001), while oseltamivir prescription rates stayed the same overall (P = 0.42). Multivariate regression across both cohorts revealed that patients were less likely to receive antibiotics if RPP-PCR results were available before the end of the ED visit or if the RPP-PCR result was positive for influenza. Patients in the educational intervention cohort were also less likely to receive an antibiotic prescription.

Conclusion

This study provides evidence that RPP-PCR results are most helpful if available prior to the end of the provider-patient interaction. Further, these data suggest that detection of influenza remains an influential result in the context of antimicrobial treatment decision making. In addition, these data contribute to the body of literature which supports comprehensive ASP interventions including leadership and patient engagement.

Panels and Syndromic Testing in Clinical Microbiology

Syndromic panels have allowed clinical microbiology laboratories to rapidly identify bacteria, viruses, fungi, and parasites and are now fully integrated into the standard testing practices of many clinical laboratories. To maximize the benefit of syndromic testing, laboratories must implement strict measures to ensure that syndromic panels are being used responsibly. This article discusses commercially available syndromic panels, the benefits and limitations of testing, and how diagnostic and laboratory stewardship can be used to optimize testing and improve patient care while keeping costs at a minimum.

Early Oseltamivir After Hospital Admission Is Associated With Shortened Hospitalization: A 5-Year Analysis of Oseltamivir Timing and Clinical Outcomes

BACKGROUND

Neuraminidase inhibitors (NAIs) are the only effective therapy for influenza, but few studies have assessed the impact of early NAI therapy on clinical outcomes or the patient-level factors that determine early NAI delivery in hospitalized patients.

METHODS

We conducted a retrospective cohort study of all adults hospitalized in a metropolitan tertiary care hospital with confirmed influenza from April 2009 to March 2014. We performed logistic regression to determine patient-level factors that were associated with early NAI therapy. We analyzed the association of early NAI therapy with hospital lengths of stay (LOS) and in-hospital mortality rates using linear and logistic regression, respectively.

RESULTS

In total, 699 patients were admitted with influenza during the 5 influenza seasons. Of those, 582 (83.4%) received NAI therapy; however, only 26.0% received the first dose within 6 hours of hospitalization (early NAI). Patients with diabetes mellitus or pregnancy were more likely to receive early NAI (P = .01, vs. P < .001 in those without these conditions), as were those reporting fever or myalgias at presentation (P = .002, vs. P = .005 without). Immunosuppressed patients were less likely to receive early NAI (P = .04). Early NAI was associated with shorter hospital LOS (P < .001). No patients died in the early NAI group, compared to 18 deaths in the 399 patients receiving NAI after 6 hours (4.5%) and 4 deaths in the 116 patients not receiving NAI (3.4%).

CONCLUSIONS

Over multiple influenza seasons, early NAI therapy was associated with shorter LOS in patients admitted with influenza. This suggests that efforts should focus on facilitating earlier therapy in patients with suspected influenza.

Severe influenza/respiratory syncytial virus infections and hospital antimicrobial stewardship opportunities: impact of a 4-year surveillance including molecular diagnosis

OBJECTIVE

To assess the prevalence of influenza and respiratory syncytial virus (RSV) in adults hospitalized for a respiratory infection in the winter months and to evaluate the impact of a viral diagnosis on empirical antimicrobial management (antibiotics and antivirals).

DESIGN

Observational cohort study.

SETTING

Acute-care university hospital.

PATIENTS

The study included 963 adult patients hospitalized over a 4-year surveillance period.

METHODS

Annual surveillance timelines were defined according to epidemiological criteria related to the circulation of RSV and influenza viruses in the general population. Patients were screened following a severe acute respiratory infection (SARI) case definition at the emergency department and were enrolled for molecular assay targeting influenza/RSV viruses after oral informed consent. Epidemiological and clinical data were recorded prospectively, microbiological investigations, antimicrobial management, and outcome data were reviewed retrospectively.

RESULTS

An influenza or RSV virus was documented in 316 of 963 patients (33%). Optimization of antimicrobial management (AM) was achieved in 162 of 265 patients (61%) with a positive viral diagnosis and no bacterial infection at admission (AM treatment not initiated, n = 111; discontinued, n = 51). In contrast, only 128 of 462 patients (28%) with negative microbiological investigations did not have AM treatment initiated (n = 116) or had such treatment discontinued (n = 12). Early, targeted antiviral treatment was prescribed in 235 of 253 patients (93%) confirmed with influenza. Epidemiological, clinical, and outcome data were similar in both groups.

CONCLUSION

Epidemiological surveillance associated with influenza/RSV molecular diagnosis in adults hospitalized for severe winter respiratory infections dramatically enhanced antimicrobial management.

Noninterruptive Clinical Decision Support Decreases Ordering of Respiratory Viral Panels during Influenza Season

OBJECTIVE

A growing body of evidence suggests that testing for influenza virus alone is more appropriate than multiplex respiratory viral panel (RVP) testing for general populations of patients with respiratory tract infections. We aimed to decrease the proportion of RVPs out of total respiratory viral testing ordered during influenza season.

METHODS

We implemented two consecutive interventions: reflex testing for RVPs only after a negative influenza test, and noninterruptive clinical decision support (CDS) including modifications of the computerized physician order entry search behavior and cost display. We conducted an interrupted time series of RVPs and influenza polymerase chain reaction tests pre- and postintervention, and performed a mixed-effects logistic regression analysis with a primary outcome of proportion of RVPs out of total respiratory viral tests. The primary predictor was the intervention period, and covariates included the provider, clinical setting, associated diagnoses, and influenza incidence.

RESULTS

From March 2013 to April 2019, there were 24,294 RVPs and 26,012 influenza tests (n = 50,306). Odds of ordering an RVP decreased during the reflex testing period (odds ratio: 0.432, 95% confidence interval: 0.397-0.469), and decreased more dramatically during the noninterruptive CDS period (odds ratio: 0.291, 95% confidence interval: 0.259-0.327).

DISCUSSION

The odds of ordering an RVP were 71% less with the noninterruptive CDS intervention, which projected 4,773 fewer RVPs compared with baseline. Assuming a cost equal to Medicare reimbursement rates for RVPs and influenza tests, this would generate an estimated averted cost of $1,259,474 per year.

CONCLUSION

Noninterruptive CDS interventions are effective in reducing unnecessary and expensive testing, and avoid typical pitfalls such as alert fatigue.

Impact of decreasing cerebrospinal fluid enterovirus PCR turnaround time on costs and management of children with suspected enterovirus meningitis

To estimate the impact of implementing in-hospital enterovirus (EV) polymerase chain reaction (PCR) testing of cerebrospinal fluid (CSF) with same-day turn-around-time (TAT) on length-of-stay (LOS), antibiotic use and on cost per patient with suspected EV meningitis, compared with testing at an outside reference laboratory. A model-based analysis using a retrospective cohort of all hospitalized children with CSF EV PCR testing done between November 2013 and 2017. The primary outcome measured was the potential date of discharge if the EV PCR result had been available on the same day. Patients with positive EV PCR were considered for potential earlier discharge once clinically stable with no reason for hospitalization other than intravenous antibiotics. Descriptive statistics and cost-sensitivity analyses were performed. CSF EV PCR testing was done on 153 patients, of which 44 (29%) had a positive result. Median test TAT was 5.3 days (IQR 3.9–7.6). Median hospital LOS was 5 days (IQR 3–12). Most (86%) patients received intravenous antibiotics with mean duration of 5.72 ± 6.51 days. No patients with positive EV PCR had a serious bacterial infection. We found that same-day test TAT would reduce LOS and duration of intravenous antibiotics by 0.50 days (95%CI 0.33–0.68) and 0.67 days (95%CI 0.42–0.91), respectively. Same-day test TAT was associated with a cost reduction of 342.83CAD (95%CI 178.14–517.00) per patient with suspected EV meningitis. Compared with sending specimens to a reference laboratory, performing CSF EV PCR in-hospital with same-day TAT was associated with decreased LOS, antibiotic therapy, and cost per patient.

Combining Procalcitonin and Rapid Multiplex Respiratory Virus Testing for Antibiotic Stewardship in Older Adult Patients With Severe Acute Respiratory Infection

OBJECTIVES

Virus infection is underevaluated in older adults with severe acute respiratory infections (SARIs). We aimed to evaluate the clinical impact of combining point-of-care molecular viral test and serum procalcitonin (PCT) level for antibiotic stewardship in the emergency department (ED).

DESIGN

A prospective twin-center cohort study was conducted between January 2017 and March 2018.

SETTING AND PARTICIPANTS

Older adult patients who presented to the ED with SARIs received a rapid molecular test for 17 respiratory viruses and a PCT test.

MEASURES

To evaluate the clinical impact, we compared the outcomes of SARI patients between the experimental cohort and a propensity score-matched historical cohort. The primary outcome was the proportion of antibiotics discontinuation or de-escalation in the ED. The secondary outcomes included duration of intravenous antibiotics, length of hospital stay, and mortality.

RESULTS

A total of 676 patients were included, of which 169 patients were in the experimental group and 507 patients were in the control group. More than one-fourth (27.9%) of the patients in the experimental group tested positive for virus. Compared with controls, the experimental group had a significantly higher proportion of antibiotics discontinuation or de-escalation in the ED (26.0% vs 16.1%, P = .007), neuraminidase inhibitor uses (8.9% vs 0.6%, P < .001), and shorter duration of intravenous antibiotics (10.0 vs 14.5 days, P < .001).

CONCLUSIONS AND IMPLICATIONS

Combining rapid viral surveillance and PCT test is a useful strategy for early detection of potential viral epidemics and antibiotic stewardship. Clustered viral respiratory infections in a nursing home is common. Patients transferred from nursing homes to ED may benefit from this approach.

Impact of multiplex respiratory virus testing on antimicrobial consumption in adults in acute care: a randomized clinical trial

Objectives

Inappropriate use of antibiotics is associated with development of antimicrobial resistance. In respiratory infections it is often difficult to differentiate between viral and bacterial infections, and empirical treatment is common. Enhanced viral testing is expected to clarify clinical decision-making and reduce the prescription of antibacterial agents, but the impact of such information on patient care is unclear.

Methods

We conducted a (1:1) randomized controlled clinical trial involving 998 adults with respiratory symptoms, fever, chest pain or poor general condition in the emergency unit of a tertiary hospital. Multiplex PCR results for 496 patients were available in 24 hours (intervention group) and those for the remaining 502 patients were available in 7 days (control group). Our primary outcome measures were the duration of hospitalization and the consumption of antibiotics within 30 days of enrolment.

Results

In all, 841 of 998 (84%) patients had respiratory symptoms at study entry. A respiratory virus was detected in 175 (17.5%). The mean duration of hospitalization was 4.2 days (SD 5.4) in the intervention group and 4.1 days (SD 4.9) in the control group (difference 0.1, 95% CI –0.5 to 0.6, p 0.810). The mean days on antibiotics were 11.3 days (SD 12.6) in the intervention group and 10.4 days (SD 11.4) in the control group (difference 0.9, 95% CI –0.6 to 2.4, p 0.235).

Conclusions

Multiplex PCR testing for respiratory viruses with results available within 24 hours did not reduce the consumption of bacterial antibiotics or the length of hospital stay in adults presenting with respiratory symptoms, fever, chest pain or reduced general condition in acute care.

Opportunities Revealed for Antimicrobial Stewardship and Clinical Practice with Implementation of a Rapid Respiratory Multiplex Assay

Few studies assess the utility of rapid multiplex molecular respiratory panels in adult patients. Previous multiplex PCR assays took hours to days from order time to result. We analyze the clinical impact of switching to a molecular assay with a 3-h test-turnaround-time (TAT). We performed a retrospective review of adult patients who presented to our emergency departments with respiratory symptoms and had a respiratory viral panel (xTAG RVP; RVP) or respiratory pathogen panel (ePlex RP; RPP) within 48 h of presentation. The average TATs for the RVP and RPP were 27.9 and 3.0 h, respectively (P < 0.0001). In RVP-positive and RPP-positive patients, 68.9 and 44.5% of those with normal chest imaging received antibiotics (P = 0.013), while 95.4 and 89.6% of those with abnormal imaging received antibiotics, respectively (P = 0.187). There was no difference in antibiotic duration in RVP-positive and RPP-positive patients with abnormal chest imaging (6.2 and 6.0 days, respectively; P = 0.923) and normal chest imaging (4.5 and 4.3 days, respectively; P = 0.922). Fewer patients were admitted in the RPP-positive compared to the RVP-positive group (76.9 and 88.6%, respectively; P = 0.013), while the proportion of admissions were similar among RPP-negative and RVP-negative patients (85.3 and 87.1%, P = 0.726). Switching to a multiplex respiratory panel with a clinically actionable TAT is associated with reduced hospital admissions and, in admitted adults without focal radiographic findings, reduced antibiotic initiation. Opportunities to further mitigate inappropriate antibiotic use may be realized by combining rapid multiplex PCR with provider education, clinical decision-care algorithms, and active antibiotic stewardship.

Cost-Effective Respiratory Virus Testing

The timely and accurate diagnosis of respiratory virus infections has the potential to optimize downstream (posttesting) use of limited health care resources, including antibiotics, antivirals, ancillary testing, and inpatient and emergency department beds. Cost-effective algorithms for respiratory virus testing must take into consideration numerous factors, including which patients should be tested, what testing should be performed (for example, antigen testing versus reverse transcription-PCR testing or influenza A/B testing versus testing with a comprehensive respiratory virus panel), and the turnaround time necessary to achieve the desired posttesting outcomes. Despite the clinical impact of respiratory virus infections, the cost-effectiveness of respiratory virus testing is incompletely understood. In this article, we review the literature pertaining to the cost-effectiveness of respiratory virus testing in pediatric and adult patient populations, in emergency department, outpatient, and inpatient clinical settings. Furthermore, we consider the cost-effectiveness of a variety of testing methods, including rapid antigen tests, direct fluorescent antibody assays, and nucleic acid amplification tests.

Disease severity and clinical outcomes of community-acquired pneumonia caused by non-influenza respiratory viruses in adults: a multicentre prospective registry study from the CAP-China Network

Although broad knowledge of influenza viral pneumonia has been established, the significance of non-influenza respiratory viruses in community-acquired pneumonia (CAP) and their impact on clinical outcomes remains unclear, especially in the non-immunocompromised adult population.Hospitalised immunocompetent patients with CAP were prospectively recruited from 34 hospitals in mainland China. Respiratory viruses were detected by molecular methods. Comparisons were conducted between influenza and non-influenza viral infection groups.In total, 915 out of 2336 adult patients with viral infection were enrolled in the analysis, with influenza virus (28.4%) the most frequently detected virus, followed by respiratory syncytial virus (3.6%), adenovirus (3.3%), human coronavirus (3.0%), parainfluenza virus (2.2%), human rhinovirus (1.8%) and human metapneumovirus (1.5%). Non-influenza viral infections accounted for 27.4% of viral pneumonia. Consolidation was more frequently observed in patients with adenovirus infection. The occurrence of complications such as sepsis (40.1% versus 39.6%; p=0.890) and hypoxaemia (40.1% versus 37.2%; p=0.449) during hospitalisation in the influenza viral infection group did not differ from that of the non-influenza viral infection group. Compared with influenza virus infection, the multivariable adjusted odds ratios of CURB-65 (confusion, urea >7 mmol·L^-1, respiratory rate ≥30 breaths·min^-1, blood pressure <90 mmHg (systolic) or ≤60 mmHg (diastolic), age ≥65 years) ≥3, arterial oxygen tension/inspiratory oxygen fraction <200 mmHg, and occurrence of sepsis and hypoxaemia for non-influenza respiratory virus infection were 0.87 (95% CI 0.26-2.84), 0.72 (95% CI 0.26-1.98), 1.00 (95% CI 0.63-1.58) and 1.05 (95% CI 0.66-1.65), respectively. The hazard ratio of 90-day mortality was 0.51 (95% CI 0.13-1.91).The high incidence of complications in non-influenza viral pneumonia and similar impact of non-influenza respiratory viruses relative to influenza virus on disease severity and outcomes suggest more attention should be given to CAP caused by non-influenza respiratory viruses.

Optimizing treatment of respiratory tract infections in nursing homes: Nurse-initiated polymerase chain reaction testing

BACKGROUND

Diagnostic testing using polymerase chain reaction (PCR) is infrequently initiated for diagnosis of respiratory tract infections (RTIs) in nursing homes. The objectives of this study were to determine the feasibility of implementing nurse-initiated PCR testing of respiratory specimens in nursing home settings and to compare antibiotic prescribing prior to and during the implementation.

METHODS

This was a pragmatic, historically controlled study in 3 nursing homes (181 total beds) in Melbourne, Australia.

RESULTS

The number of PCR tests of respiratory specimens (over 12 months) increased from 5 to 67 when nurses could initiate the tests. Residents with RTI symptoms had a virus identified by PCR in 50.7% of tests, including 14 positive for influenza. Six outbreaks were identified. When clustering was taken into consideration, incidence rates of antibiotic days of therapy did not change (incidence rate ratio = 0.94, 95% confidence interval, 0.25-3.35, P = .92) despite identification of more viral pathogens.

CONCLUSIONS

In nursing homes, nurse-initiated PCR testing of respiratory specimens is feasible and useful in terms of identifying the cause of many RTIs and outbreaks, and viruses are common in this context. However, the current study suggests the availability of these test results alone does not impact antibiotic prescribing.

Positive Impact of a Point-of-Care Molecular Influenza Test in the Emergency Department During the 2017-2018 Seasonal Influenza Epidemic

During the 2017-2018 flu epidemic, the point-of-care Alere-i (n = 72) and reverse transcription polymerase chain reaction (n = 106) tests were compared. Patients in the point-of-care group were administered oseltamivir significantly more rapidly (9 hours vs 23 hours), they spent less time in the emergency department, and they had lower rates of antibiotic administration and hospitalization.

Contribution of the FilmArray Respiratory Panel in the management of adult and pediatric patients attending the emergency room during 2015-2016 influenza epidemics: An interventional study

AIM

To evaluate the contribution of a multiplex PCR for respiratory viruses on antibiotic and antiviral prescription, ancillary test prescription, admission and length of stay of patients.

METHODS

Two hundred ninety-one adult and pediatric patients visiting the emergency department during the 2015-2016 influenza epidemic were prospectively included and immediately tested 24/7 using the FilmArray Respiratory Panel. The results were communicated to the practitioner in charge as soon as they became available. Clinical and biological data were gathered and analyzed.

FINDINGS

Results from the FilmArray Respiratory Panel do not appear to impact admission or antibiotic prescription, with the exception of a lower admission rate for children who tested positive for influenza B. Parameters that account for the clinical decisions evaluated are CRP level, white blood cell count, suspected or proven bacterial infection and, for adult patients only, signs of respiratory distress. Length of stay is also not significantly different between patients with a positive and a negative result. A rapid influenza test result permits a more appropriate prescription of oseltamivir.

What is the role of rapid molecular testing for seniors and other at-risk adults with respiratory syncytial virus infections?

Lower respiratory tract infections are a leading cause of hospitalization and viruses are important causal pathogens, especially in the elderly, immunocompromised patients and those with respiratory or cardiovascular comorbidities. Respiratory syncytial virus (RSV) is recognized as comprising a substantial burden of morbidity and mortality in older and at-risk adults, and the emergence of rapid point-of-care molecular testing has made it possible to confirm an RSV diagnosis accurately, in a clinically actionable timeframe. RSV patients have significantly higher healthcare resource use (including hospital stays and emergency room/urgent care visits) than non-RSV matched controls, especially if aged ≥65 years, a longer length of hospitalization than those with influenza, and associated costs nearly three times higher. We found no direct clinical outcome data specific to rapid molecular testing for RSV in adults and very little in children. There is very limited evidence that prompt diagnosis may reduce hospital length of stay but this and other outcome parameters need confirmation in larger, prospective clinical trials. Regarding reducing inappropriate antibiotic prescribing, the picture is mixed and testing alone is unlikely to change entrenched habits. There is little incentive for clinicians to order routine RSV tests in adults given the absence of a specific antiviral therapy. However, with numerous vaccine and antiviral candidates in clinical development, we believe it is good practice to plan and start establishing standardized testing protocols - perhaps as part of outcome studies. For especially vulnerable patients, e.g., immunocompromised and transplant patients, prompt accurate RSV diagnosis may prevent disease spread and save lives.

Respiratory tract virus infections in the elderly with pneumonia

BACKGROUND

In children suffering from severe lower airway illnesses, respiratory virus detection has given good prognostic information, but such reports in the elderly are scarce. Therefore, our aim was to study whether the detection of nasopharyngeal viral pathogens and conventional inflammatory markers in the frail elderly correlate to the presence, signs and symptoms or prognosis of radiographically-verified pneumonia.

METHODS

Consecutive episodes of hospital care of patients 65 years and older with respiratory symptoms (N = 382) were prospectively studied as a cohort. Standard clinical questionnaire was filled by the study physician. Laboratory analyses included PCR diagnostics of nasopharyngeal swab samples for 14 respiratory viruses, C-reactive protein (CRP) and white blood cell count (WBC). Chest radiographs were systematically analysed by a study radiologist. The length of hospital stay, hospital revisit and death at ward were used as clinical endpoints.

RESULTS

Median age of the patients was 83 years (range 76-90). Pneumonia was diagnosed in 112/382 (29%) of the studied episodes. One or more respiratory viruses were detected in 141/382 (37%) episodes and in 34/112 (30%) episodes also diagnosed with pneumonia. Pneumonia was associated with a WBC over 15 × 10⁹/L (P = .006) and a CRP value over 80 mg/l (P < .05). A virus was detected in 30% of pneumonia episodes and in 40% of non-pneumonia episodes, but this difference was not significant (P = 0.09). The presence of a respiratory virus was associated with fewer revisits to the hospital (P < .05), whereas a CRP value over 100 mg/l was associated with death during hospital stay (P < .05). Respiratory virus detections did not correlate to WBC or CRP values, signs and symptoms or prognosis of radiographically-verified pneumonia episodes.

CONCLUSION

Among the elderly with respiratory symptoms, respiratory virus detection was not associated with an increased risk of pneumonia or with a more severe clinical course of the illness. CRP and WBC remain important indicators of pneumonia, and according to our findings, pneumonia should be treated as a bacterial disease regardless of the virus findings. Our data does not support routine virus diagnostics for the elderly patients with pneumonia outside the epidemic seasons.

Viral pathogens associated with acute respiratory illness in hospitalized adults and elderly from Zagreb, Croatia, 2016 to 2018

Aims

To investigate the viral etiology of acute respiratory infection (ARI) in hospitalized adults and elderly patients in Croatia, compare the prevalence of detected viruses, and to determine clinical characteristics and seasonal occurrence of investigated infections.

Methods

From January 2016 to June 2018, a total of 182 adult patients presented with symptoms of ARI and admitted to the hospital were tested for 15 respiratory viruses by multiplex reverse‐transcription polymerase chain reaction. Clinical data were collected by retrospective analysis of the patient's chart.

Results

A virus was identified in 106 (58.5%) of the patients. The most commonly detected virus was influenza virus (41.5%), followed by respiratory syncytial virus (13.8%), human metapneumovirus (13.0%), parainfluenza viruses (12.2%), rhinoviruses (11.4%), adenovirus and coronaviruses with equal frequencies (3.3%), and enterovirus (1.6%). The serum level of C‐reactive protein and white blood cell count were significantly lower in patients with respiratory viruses identified when compared with those in whom no virus was detected (P < 0.001 and P = 0.007, respectively). There were no differences in clinical symptoms according to the type of the detected virus, except for more frequent illness exposure recall for influenza infection ( P = 0.010). Influenza, parainfluenza, and pneumoviruses were detected mostly in winter months, while rhinoviruses in autumn and spring.

Conclusions

In addition to influenza, pneumoviruses, rhinoviruses, and parainfluenza viruses play an important role in etiology of ARIs in adults. Fast and accurate laboratory diagnosis for respiratory viruses in routine practice is needed for clinicians optimally manage patients with ARI and potentially avoid the unnecessary use of antimicrobial drugs.

Antimicrobial Stewardship in the Emergency Department

The emergency department (ED) is the hub of the US health care system. Acute infectious diseases are frequently encountered in the ED setting, making this a critical setting for antimicrobial stewardship efforts. Systems level and behavioral stewardship interventions have demonstrated success in the ED setting but successful implementation depends on institutional support and the presence of a physician champion. Antimicrobial stewardship efforts in the ED should target high-impact areas: antibiotic prescribing for nonindicated respiratory tract conditions, such as bronchitis and sinusitis; overtreatment of asymptomatic bacteriuria; and using two antibiotics (double coverage) for uncomplicated cases of cellulitis or abscess.

Current and Future Opportunities for Rapid Diagnostics in Antimicrobial Stewardship

Rapid diagnostic testing has improved clinical care of patients with infectious syndromes when combined with antimicrobial stewardship. The authors review the current data on antimicrobial stewardship and rapid diagnostic testing in bloodstream, respiratory tract, and gastrointestinal tract infections. Evidence for the potential benefit of rapid tests in bloodstream infections seems strong, respiratory tract infections mixed, and gastrointestinal tract infections still evolving. The authors also review future directions in rapid diagnostic testing and suggest areas of focus for antimicrobial stewardship efforts.

Testing for Respiratory Viruses in Adults With Severe Lower Respiratory Infection

Viral pathogens are a common cause of severe lower respiratory tract infection in adults. Our ability to rapidly and accurately identify viral infections has dramatically improved as slow culture-based techniques have been largely replaced by multiplex high-throughput systems. Given these advances, reevaluation of the role of respiratory viral testing in adults presenting with lower respiratory tract infection is important. This article reviews the potential benefits of testing, provides an overview of the most commonly used diagnostic techniques, and considers whether current evidence supports routine testing.

Saliva as a diagnostic specimen for testing respiratory virus by a point-of-care molecular assay: a diagnostic validity study

OBJECTIVES

Automated point-of-care molecular assays have greatly shortened the turnaround time of respiratory virus testing. One of the major bottlenecks now lies at the specimen collection step, especially in a busy clinical setting. Saliva is a convenient specimen type that can be provided easily by adult patients. This study assessed the diagnostic validity, specimen collection time and cost associated with the use of saliva.

METHODS

This was a prospective diagnostic validity study comparing the detection rate of respiratory viruses between saliva and nasopharyngeal aspirate (NPA) among adult hospitalized patients using Xpert^® Xpress Flu/RSV. The cost and time associated with the collection of saliva and nasopharyngeal specimens were also estimated.

RESULTS

Between July and October 2017, 214 patients were recruited. The overall agreement between saliva and NPA was 93.3% (196/210, κ 0.851, 95% CI 0.776-0.926). There was no significant difference in the detection rate of respiratory viruses between saliva and NPA (32.9% (69/210) versus 35.7% (75/210); p 0.146). The overall sensitivity and specificity were 90.8% (81.9%-96.2%) and 100% (97.3%-100%), respectively, for saliva, and were 96.1% (88.9%-99.2%) and 98.5% (94.7%-99.8%), respectively, for NPA. The time and cost associated with the collection of saliva were 2.26-fold and 2.59-fold lower, respectively, than those of NPA.

CONCLUSIONS

Saliva specimens have high sensitivity and specificity in the detection of respiratory viruses by an automated multiplex Clinical Laboratory Improvement Amendments-waived point-of-care molecular assay when compared with those of NPA. The use of saliva also reduces the time and cost associated with specimen collection.

Rapid Molecular Detection of Gastrointestinal Pathogens and Its Role in Antimicrobial Stewardship

We aimed to detect the etiological agents of acute diarrhea by a molecular gastrointestinal pathogen test (MGPT) and to assess the impact of MGPT on antimicrobial stewardship programs (ASP). This is a prospective observational study and was conducted between 1 January 2015 and 30 June 2017. We included consequent patients who had acute diarrhea. At the end of 2015, we implemented ASP in acute diarrhea cases and compared the outcomes in the pre-ASP and post-ASP periods. An FDA-cleared multiplexed gastrointestinal PCR panel system, the BioFire FilmArray (Idaho Technology, Salt Lake City, UT), which detects 20 pathogens in stool, was used. In 499 out of 699 patients (71%), at least one pathogen was detected. Among 314 adults with positive MGPT, 101 (32%) enteropathogenic Escherichia coli (EPEC), 71 (23%) enteroaggregative E. coli (EAEC), 68 (22%) enterotoxigenic E. coli (ETEC), 55 (18%) Shiga toxin-producing E. coli (STEC) (17%) Norovirus, 48 (15%) Campylobacter, 21 (7%) Salmonella, and 20 (6%) Clostridium difficile strains were detected. Among 185 children, 55 (30%) EPEC, 37 (20%) C. difficile, 32 (17%) Norovirus, 29 (16%) EAEC, 22 (12%) STEC, 21 (11%) ETEC, 21 (11%) Campylobacter, 20 (11%) Salmonella, and 16 (5%) Rotavirus strains were detected. Inappropriate antibiotic use decreased in the post-ASP period compared with the pre-ASP period among inpatients (42.9% and 25.8%, respectively; P = 0.023). Using MGPT in clinical practice significantly decreased the unnecessary use of antibiotics. Detection of high rates of C. difficile in children and Salmonella spp., as well as relatively high rates of Campylobacter spp., which were hard to isolate by routine stool culture, were remarkable.

Diagnostic yield and clinical impact of routine cell culture for respiratory viruses among children with a negative multiplex RT-PCR result

•

4.2% of PCR-negative respiratory specimens were positive in viral culture.

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Half of the recovered viruses were not part of the multiplex PCR panel.

•

Routine viral culture on PCR-negative respiratory specimens had minimal clinical impact.

•

The findings of this study may help resource utilization in the virology laboratory.

Background

Polymerase chain reaction (PCR) is the reference standard for respiratory virus testing. However, cell culture may still have added value in identifying viruses not detected by PCR.

Objectives

We aimed to estimate the yield and clinical impact of routine respiratory virus culture among children with a negative PCR result.

Study design

A retrospective cohort study was performed from Jan. 2013 to Sept. 2015. Respiratory samples from hospitalized or immunocompromised patients <18 years old were routinely inoculated on traditional tube cell culture monolayers if they tested negative by a PCR assay for 12 respiratory viruses. We studied patients with a respiratory specimen negative by PCR and positive by culture. Duplicates and samples of sold services were excluded. Data on demographics, clinical history, laboratory findings, and patient management were collected from patients’ charts. Descriptive and multivariate statistics were performed.

Results

Overall, 4638 PCR-negative samples were inoculated in cell culture. Of those, 196 (4.2%) were cell culture positive, and 144 met study inclusion criteria. Most subjects (81.9%) were hospitalized. Mean age was 2.4 ± 3.4 years. The viruses most frequently isolated were cytomegalovirus (33.3%) and enteroviruses (19.4%). Cell culture results prompted a change in management in 5 patients (3.5%), all of whom had acyclovir initiated for localized HSV-1 infection. Four of these had skin or mucosal lesions that could be sampled to establish a diagnosis.

Conclusion

In children, routine viral culture on respiratory specimens that were negative by PCR has low yield and minimal clinical impact.