Point-of-care influenza testing impacts clinical decision, patient flow and length of stay in hospitalized adults

European society of clinical microbiology and infectious diseases guidelines for antimicrobial stewardship in emergency departments (endorsed by European association of hospital pharmacists)

SCOPE

This European Society of Clinical Microbiology and Infectious Diseases guideline provides evidence-based recommendations to support a selection of appropriate antibiotic use practices for patients seen in the emergency department (ED) and guidance for their implementation. The topics addressed in this guideline are (a) Do biomarkers or rapid pathogen tests improve antibiotic prescribing and/or clinical outcomes? (b) Does taking blood cultures in common infectious syndromes improve antibiotic prescribing and/or clinical outcomes? (c) Does watchful waiting without antibacterial therapy or with delayed antibiotic prescribing reduce antibiotic prescribing without worsening clinical outcomes in patients with specific infectious syndromes? (d) Do structured culture follow-up programs in patients discharged from the ED with cultures pending improve antibiotic prescribing?

METHODS

An expert panel was convened by European Society of Clinical Microbiology and Infectious Diseases and the guideline chair. The panel selected in consensus the four most relevant antimicrobial stewardship topics according to pre-defined relevance criteria. For each main question for the four topics, a systematic review was performed, including randomized controlled trials and observational studies. Both clinical outcomes and stewardship process outcomes related to antibiotic use were deemed relevant. The literature searches were conducted between May 2021 and March 2022. In April 2022, the panel members were formally asked to suggest additional studies that were not identified in the initial searches. Data were summarized in a meta-analysis if possible or otherwise summarized narratively. The certainty of the evidence was classified according to the Grading of Recommendations Assessment, Development and Evaluation criteria. The guideline panel reviewed the evidence per topic critically appraising the evidence and formulated recommendations through a consensus-based process. The strength of the recommendations was classified as strong or weak. To substantiate the implementation process, implementation trials or observational studies describing facilitators/barriers for implementation were identified from the same searches and were summarized narratively.

RECOMMENDATIONS

The recommendations on the use of biomarkers and rapid pathogen diagnostic tests focus on the initiation of antibiotics in patients admitted through the ED. Their effect on the discontinuation or de-escalation of antibiotics during hospital stay was not reported, neither was their effect on hospital infection prevention and control practices. The recommendations on watchful waiting (i.e. withholding antibiotics with some form of follow-up) focus on specific infectious syndromes for which the primary care literature was also included. The recommendations on blood cultures focus on the indication in three common infectious syndromes in the ED explicitly excluding patients with sepsis or septic shock. Most recommendations are based on very low and low certainty of evidence, leading to weak recommendations or, when no evidence was available, to best practice statements. Implementation of these recommendations needs to be adapted to the specific settings and circumstances of the ED. The scarcity of high-quality studies in the area of antimicrobial stewardship in the ED highlights the need for future research in this field.

Syndromic testing for respiratory pathogens but not National Early Warning Score can be used to identify viral cause in hospitalised adults with lower respiratory tract infections

BACKGROUND

Community-acquired lower respiratory tract infection (LRTI) is a common reason for hospitalisation. Antibiotics are frequently used while diagnostic microbiological methods are underutilised in the acute setting.

OBJECTIVES

We aimed to investigate the relative proportion of viral and bacterial infections in this patient group and explore methods for proper targeting of antimicrobial therapy.

METHODS

We collected nasopharyngeal samples prospectively from adults hospitalised with LRTIs during three consecutive winter seasons (2016-2019). Syndromic nasopharyngeal testing was performed using a multiplex PCR panel including 16 viruses and four bacteria. Medical records were reviewed for clinical data.

RESULTS

Out of 220 included patients, a viral pathogen was detected in 74 (34%), a bacterial pathogen in 63 (39%), both viral and bacterial pathogens in 49 (22%), while the aetiology remained unknown in 34 (15%) cases. The proportion of infections with an identified pathogen increased from 38% to 85% when syndromic testing was added to standard-of-care testing. Viral infections were associated with a low CRP level and absence of pulmonary infiltrates. A high National Early Warning Score did not predict bacterial infections.

CONCLUSIONS

Syndromic testing by a multiplex PCR panel identified a viral infection or viral/bacterial coinfection in a majority of hospitalised adult patients with community-acquired LRTIs.

Performance of the FebriDx Rapid Point-of-Care Test for Differentiating Bacterial and Viral Respiratory Tract Infections in Patients with a Suspected Respiratory Tract Infection in the Emergency Department

FebriDx is a rapid point-of-care test combining qualitative measurements of C-reactive protein (CRP) and Myxovirus Resistance Protein A (MxA) using a disposable test device to detect and differentiate acute bacterial from viral respiratory tract infections. The goal of this study was to investigate the diagnostic accuracy of FebriDx in patients with suspected respiratory tract infections in the emergency department (ED). This was an observational cohort study, performed in the ED of an academic hospital. Patients were included if they had a suspected infection. The primary outcome was the presence of a bacterial or viral infection, determined by clinical adjudication by an expert panel. The sensitivity, specificity, and positive and negative predictive value of FebriDx for the presence of bacterial versus non-bacterial infections, and viral versus non-viral infections were calculated. Between March 2019 and November 2020, 244 patients were included. A bacterial infection was present in 41%, viral infection was present in 24%, and 4% of the patients had both viral and bacterial pathogens. FebriDx demonstrated high sensitivity in the detection of bacterial infection (87%), high NPV (91%) to rule out bacterial infection, and high specificity (94%) for viral infection in patients with a suspected infection in the ED.

Effect of point-of-care influenza tests on antibiotic prescriptions by emergency physicians in a French hospital

BACKGROUND

Influenza is a public health issue worldwide. Although antibiotics should not be used to treat viral infections, they are often prescribed to patients with influenza-like illness (ILI). Such misuse promotes antibiotic resistance. The role of rapid point-of-care tests (POCT) in preventing antibiotic misuse in adults with ILI symptoms remains relatively unexplored.

AIM

To evaluate whether POCT implemented in 2018-2019 to detect influenza viruses lead to a decrease in antibiotic prescriptions compared to laboratory based influenza tests.

METHODS

Adult patients with ILI in one emergency department (ED) were retrospectively enrolled over three epidemic seasons (from 2016-2017 to 2018-2019). The primary outcome was the rate of antibiotic prescriptions, which was compared between the three seasons in bivariate and multivariate analyses. Prescriptions for ancillary laboratory tests, chest X-rays and oseltamivir were also compared, along with hospitalisations and length of stay (LOS) at the ED.

FINDINGS

Overall, 1849 patients were included. Median age was over 70 throughout all three seasons. The number of antibiotic prescriptions was significantly different between the three periods in bivariate analysis (48.3% in 2016/2017, 44% in 2017/2018 and 31.1% in 2018/2019; p<0,0001) and in multivariate analysis (adjusted Odds Ratio [aOR]=0.48, 95%CI=0.30-0.76 for 2018/2019 and aOR=0.99, 95%CI=0.67-1.46 for 2017/2018, compared to 2016/2017). There were significantly fewer prescriptions of ancillary laboratory tests, X-rays, hospitalisations and more oseltamivir prescriptions in 2018/2019, compared to the previous seasons. LOS was significantly lower in 2018/2019 only for influenza-positive patients.

CONCLUSION

ED influenza POCT decreased antibiotic use and lead to less ancillary testing, X-rays and hospitalisations among patients with ILI. However, medico-economic studies are necessary before formulating definite recommendations.

Lower antibiotic prescription rates in hospitalized COVID-19 patients than influenza patients, a prospective study

BACKGROUND

COVID-19 patients are extensively treated with antibiotics despite few bacterial complications. We aimed to study antibiotic use in hospitalized COVID-19 patients compared to influenza patients in two consecutive years. Furthermore, we investigated changes in antibiotic use from the first to second pandemic wave.

METHODS

This prospective study included both patients from two referral hospitals in Bergen, Norway, admitted with influenza (n = 215) during the 2018/2019 epidemic and with COVID-19 (n = 82) during spring/summer 2020, and national data on registered Norwegian COVID-19 hospital admissions from March 2020 to January 2021 (n = 2300). Patient characteristics were compared, and logistic regression analysis was used to identify risk factors for antibiotic use.

RESULTS

National and local COVID-19 patients received significantly less antibiotics (53% and 49%) than influenza patients (69%, p < .001). Early antibiotics contributed to >90% of antibiotic prescriptions in the two local hospitals, and >70% of prescriptions nationally. When adjusted for age, comorbidities, symptom duration, chest X-ray infiltrates and oxygen treatment, local COVID-19 patients still had significantly lower odds of antibiotic prescription than influenza patients (aOR 0.21, 95%CI 0.09-0.50). At the national level, we observed a significant reduction in antibiotic prescription rates in the second pandemic wave compared to the first (aOR 0.35, 95% CI 0.29-0.43).

CONCLUSION

Fewer COVID-19 patients received antibiotics compared to influenza patients admitted to the two local hospitals one year earlier. The antibiotic prescription rate was lower during the second pandemic wave, possibly due to increased clinical experience and published evidence refuting the efficacy of antibiotics in treating COVID-19 pneumonia.