Evaluation of an acute point-of-care system screening for respiratory syncytial virus infection

Investigation of afebrile neonates with a history of fever

Objective:

Our objective was to describe clinically significant infections in a cohort of afebrile neonates who underwent an emergency department (ED) septic workup because of the history of a measured fever at home.

Methods:

Retrospective medical record review of all infants ≤28 days of age who presented to our tertiary care pediatric ED between Jan. 1, 1999, and Aug. 22, 2002, underwent lumbar puncture in the ED, had a reported temperature at home of ≥38°C, and an ED triage temperature of <38°C. Laboratory and radiographic results were tabulated.

Results:

During the study period, 206 neonates underwent lumbar puncture in our ED. Of these, 108 were excluded because their home temperature was not documented, and 71 were excluded because they were still febrile on presentation to the ED. The study group consisted of the remaining 27 subjects, 4 of whom had received acetaminophen prior to ED arrival. Infections were confirmed in 10 (37%) subjects (3 urinary tract infections, 2 aseptic meningitis, 1 enterovirus meningitis, 1 respiratory syncytial virus bronchiolitis, 1 rotavirus enteritis and 2 pneumonias).

Conclusions:

Clinically important infections are not uncommon among afebrile neonates undergoing ED septic workup because of a measured fever at home. Some diagnostic testing is warranted in this group, although the clinical utility and indications for specific test modalities remain unclear.

Rapid viral diagnosis for acute febrile respiratory illness in children in the Emergency Department

BACKGROUND

Pediatric acute respiratory infections (ARIs) represent a significant burden on pediatric Emergency Departments (EDs) and families. Most of these illnesses are due to viruses. However, investigations (radiography, blood, and urine testing) to rule out bacterial infections and antibiotics are often ordered because of diagnostic uncertainties. This results in prolonged ED visits and unnecessary antibiotic use. The risk of concurrent bacterial infection has been reported to be negligible in children over three months of age with a confirmed viral infection. Rapid viral testing in the ED may alleviate the need for precautionary testing and antibiotic use.

OBJECTIVES

To determine if the use of a rapid viral detection test for children with an acute respiratory infection (ARI) in Emergency Departments (EDs) changes patient management and resource use in the ED, compared to not using a rapid viral detection test. We hypothesized that rapid viral testing reduces antibiotic use in the ED as well as reduces the rate of ancillary testing and length of ED visits.

SEARCH METHODS

We searched CENTRAL (2014, Issue 6), MEDLINE (1950 to July week 1, 2014), MEDLINE In-Process & Other Non-Indexed Citations (15 July 2014), EMBASE.com (1988 to July 2014), HealthStar (1966 to 2009), BIOSIS Previews (1969 to July 2014), CAB Abstracts (1973 to July 2014), CBCA Reference (1970 to 2007) and ProQuest Dissertations and Theses (1861 to 2009).

SELECTION CRITERIA

Randomized controlled trials (RCTs) of rapid viral testing for children with ARIs in the ED.

DATA COLLECTION AND ANALYSIS

Two review authors used the inclusion criteria to select trials, evaluate their quality, and extract data. We obtained missing data from trial authors. We expressed differences in rate of investigations and antibiotic use as risk ratios (RRs), and expressed difference in ED length of visits as mean differences (MDs), with 95% confidence intervals (CIs).

MAIN RESULTS

No new trials were identified in this 2014 update. We included four trials (three RCTs and one quazi-RCT), with 759 children in the rapid viral testing group and 829 in the control group. Three out of the four studies were comparable in terms of young age of participants, with one study increasing the age of inclusion up to five years of age. All studies included either fever or respiratory symptoms as inclusion criteria (two required both, one required fever or respiratory symptoms, and one required only fever). All studies were comparable in terms of exclusion criteria, intervention, and outcome data. In terms of risk of bias, one study failed to utilize a random sequence generator, one study did not comment on completeness of outcome data, and only one of four studies included allocation concealment as part of the study design. None of the studies definitively blinded participants.Rapid viral testing resulted in a trend toward decreased antibiotic use in the ED, but this was not statistically significant. We found lower rates of chest radiography (RR 0.77, 95% CI 0.65 to 0.91) in the rapid viral testing group, but no effect on length of ED visits, or blood or urine testing in the ED. No study made mention of any adverse effects related to viral testing.

AUTHORS' CONCLUSIONS

There is insufficient evidence to support routine rapid viral testing to reduce antibiotic use in pediatric EDs. Rapid viral testing may or may not reduce rates of antibiotic use, and other investigations (urine and blood testing); these studies do not provide enough power to resolve this question. However, rapid viral testing does reduce the rate of chest X-rays in the ED. An adequately powered trial with antibiotic use as an outcome is needed.

Rapid antigen-based testing for respiratory syncytial virus: moving diagnostics from bench to bedside?

Respiratory syncytial virus (RSV) is the most important cause of infantile bronchiolitis and pneumonia. It is ubiquitous, with most children acquiring their primary infection within the first year of life and with subsequent reinfection occurring in all age groups. Clinically, RSV is virtually indistinguishable from other viral respiratory infections. Traditionally, the microbiologic diagnosis of RSV has been based on moderate to complex techniques performed in a laboratory (cell culture, nucleic acid amplification and immunofluorescence assays); however, rapid antigen-detection tests offer potential advantages associated with point-of-care testing. This review seeks to familiarize the readers with RSV rapid antigen-detection tests, describe their performance characteristics and comment on their strengths and weaknesses. The authors will discuss the impact of rapid RSV testing on clinical practice, with a look to the future of what the field ultimately requires of a point-of-care diagnostic technique.

Rapid viral diagnosis for acute febrile respiratory illness in children in the Emergency Department

BACKGROUND

Pediatric acute respiratory infections (ARIs) represent a significant burden on pediatric Emergency Departments (EDs) and families. Most of these illnesses are due to viruses. However, investigations (radiography, blood, and urine testing) to rule out bacterial infections and antibiotics are often ordered because of diagnostic uncertainties. This results in prolonged ED visits and unnecessary antibiotic use. The risk of concurrent bacterial infection has been reported to be negligible in children over three months of age with a confirmed viral infection. Rapid viral testing in the ED may alleviate the need for precautionary testing and antibiotic use.

OBJECTIVES

To determine the effect of rapid viral testing in the ED on the rate of precautionary testing, antibiotic use, and length of ED visit.

SEARCH METHODS

We searched the Cochrane Central register of Controlled Trials (CENTRAL) (The Cochrane Library 2011, Issue 4); EMBASE (1988 to December 2011); MEDLINE Ovid (1950 to November week 4, 2011); MEDLINE In-Process & Other Non-Indexed Citations (8 December 2011); HealthStar (1966 to 2009); BIOSIS Previews (1969 to December 2011); CAB Abstracts (1973 to December 2011); CBCA Reference (1970 to 2007); and Proquest Dissertations and Theses (1861 to 2009).

SELECTION CRITERIA

Randomized controlled trials (RCTs) of rapid viral testing for children with ARIs in the ED.

DATA COLLECTION AND ANALYSIS

Two review authors used the inclusion criteria to select trials, evaluate their quality and extract data. We obtained missing data from trial authors. We expressed differences in rate of investigations and antibiotic use as risk ratios (RRs), and expressed difference in ED length of visits as mean differences (MDs), with 95% confidence intervals (CIs).

MAIN RESULTS

We included four trials (three RCTs and one quazi-RCT), with 759 children in the rapid viral testing group and 829 in the control group. Three out of the four studies were comparable in terms of young age of participants, with one study increasing the age of inclusion up to five years of age. All studies included either fever or respiratory symptoms as inclusion criteria (two required both, one required fever or respiratory symptoms, and one required only fever). All studies were comparable in terms of exclusion criteria, intervention, and outcome data. In terms of risk of bias, one study failed to utilize a random sequence generator, one study did not comment on completeness of outcome data, and only one of four studies included allocation concealment as part of the study design. None of the studies definitively blinded participants.Rapid viral testing did not reduce antibiotic use in the ED significantly, neither clinically nor statistically. We found lower rates of chest radiography (RR 0.77, 95% CI 0.65 to 0.91) in the rapid viral testing group, but no effect on length of ED visits, or blood or urine testing in the ED. No study made mention of any adverse effects related to viral testing.

AUTHORS' CONCLUSIONS

Current evidence is insufficient to support routine rapid viral testing as a means to reduce antibiotic use in pediatric EDs. Results suggest that rapid viral testing may be beneficial in terms of reducing rates of antibiotic usage, urine investigations and blood investigations, but are not statistically significant due to lack of power. Rapid viral testing does reduce the rate of chest X-rays in the ED. A large trial addressing the effect on antibiotic usage is needed.

Point of care testing: diagnosis outside the virology laboratory

Numerous point-of-care tests (POCTs) are available to diagnose viral infections in both hospital and community settings. The ideal POCT is rapid, sensitive, specific, and simple to perform. This chapter will describe the benefits of POCTs, factors that can influence the accuracy of POCTs and highlight some limitations of POCT strategies. The sensitivity, specificity, and turn-around time of available POCTs are included for common conditions including respiratory viral infections (e.g. influenza, RSV) and blood-borne viral infections (e.g. HIV).

Cochrane Review: Rapid viral diagnosis for acute febrile respiratory illness in children in the Emergency Department

Background

Pediatric acute respiratory infections (ARIs) represent a significant burden on pediatric emergency departments (ED) and families. Most of these illnesses are due to viruses. However, investigations (radiography, blood and urine testing) to rule out bacterial infections and antibiotics are often ordered because of diagnostic uncertainties. This results in prolonged ED visits and unnecessary antibiotic use. The risk of concurrent bacterial infection has been reported to be negligible in children over three months of age with a confirmed viral infection. Rapid viral testing in the ED may alleviate the need for precautionary testing and antibiotic use.

Objectives

To determine the effect of rapid viral testing in the ED on the rate of precautionary testing, antibiotic use and ED length of visit.

Search strategy

We searched the Cochrane Central register of Controlled Trials (CENTRAL) (The Cochrane Library, 2009, issue 1) which contains the ARI Group's Specialized Register, MEDLINE (1950 to April Week 3 2009), EMBASE (1988 to Week 16, 2009), MEDLINE In‐Process & Other Non‐Indexed Citations (April 27, 2009), HealthStar (1966 to 2009), BIOSIS Previews (1969 to 2009), CAB Abstracts (1973 to 2007), CBCA Reference (1970 to 2007), and Proquest Dissertations and Theses (1861 to 2009).

Selection criteria

Randomized controlled trials (RCTs) of rapid viral testing for children with ARIs in the ED.

Data collection and analysis

Two review authors used the inclusion criteria to select trials, evaluate their quality and extract data. Missing data were obtained from trial authors. Differences in rate of investigations and antibiotics use were expressed as risk ratios (RR) and difference in ED length of visits was expressed as mean difference, with 95% confidence interval (CI).

Main results

Four trials were included, three RCTs and one quazi‐RCT, with 759 children in the rapid viral testing and 829 in the control group. Rapid viral testing did not reduce antibiotic use in the ED significantly, neither clinically nor statistically. We found lower rates of chest radiography (RR 0.77, 95% CI 0.65 to 0.91) in the rapid viral testing group but no effect on length of ED visits, blood or urine testing in the ED.

Authors' conclusions

Current evidence is insufficient, although promising, to support routine rapid viral testing as a means to reduce antibiotic use in pediatric EDs. Results suggest that rapid viral testing may be beneficial but are not statistically significant due to lack of power. A large trial addressing these outcome measures is needed.

Plain Language Summary

Does rapid viral testing in the Emergency Department affect the treatment of children with fever and respiratory problems?

Children admitted to Emergency Departments (ED) with fever and respiratory symptoms represent a major burden to the health care system, as well as significant anxiety and expense to parents and caregivers.  Physicians often order diagnostic tests and may prescribe antibiotics when they are unsure of the cause of the illness and are concerned about the possibility of serious bacterial infection. However, in most cases, fever and respiratory symptoms are caused by viruses. In addition, in children in whom a virus is found to be the cause of their illness, the risk of serious bacterial infection is very low. This review was conducted to assess whether a rapid viral test done in the ED changes what physicians do when treating these children. We found that in previously healthy children coming to the ED with fever and respiratory symptoms, a rapid viral test reduces the use of chest X‐rays and that there is a trend toward less antibiotic usage, and blood and urine investigations. The true impact of this intervention on the latter three outcomes requires trials with larger enrollment numbers.

Rapid viral diagnosis for acute febrile respiratory illness in children in the Emergency Department

BACKGROUND

Pediatric acute respiratory infections (ARIs) represent a significant burden on pediatric emergency departments (ED) and families. Most of these illnesses are due to viruses. However, investigations (radiography, blood and urine testing) to rule out bacterial infections and antibiotics are often ordered because of diagnostic uncertainties. This results in prolonged ED visits and unnecessary antibiotic use. The risk of concurrent bacterial infection has been reported to be negligible in children over three months of age with a confirmed viral infection. Rapid viral testing in the ED may alleviate the need for precautionary testing and antibiotic use.

OBJECTIVES

To determine the effect of rapid viral testing in the ED on the rate of precautionary testing, antibiotic use and ED length of visit.

SEARCH STRATEGY

We searched the Cochrane Central register of Controlled Trials (CENTRAL) (The Cochrane Library, 2009, issue 1) which contains the ARI Group's Specialized Register, MEDLINE (1950 to April Week 3 2009), EMBASE (1988 to Week 16, 2009), MEDLINE In-Process & Other Non-Indexed Citations (April 27, 2009), HealthStar (1966 to 2009), BIOSIS Previews (1969 to 2009), CAB Abstracts (1973 to 2007), CBCA Reference (1970 to 2007), and Proquest Dissertations and Theses (1861 to 2009).

SELECTION CRITERIA

Randomized controlled trials (RCTs) of rapid viral testing for children with ARIs in the ED.

DATA COLLECTION AND ANALYSIS

Two review authors used the inclusion criteria to select trials, evaluate their quality and extract data. Missing data were obtained from trial authors. Differences in rate of investigations and antibiotics use were expressed as risk ratios (RR) and difference in ED length of visits was expressed as mean difference, with 95% confidence interval (CI).

MAIN RESULTS

Four trials were included, three RCTs and one quazi-RCT, with 759 children in the rapid viral testing and 829 in the control group. Rapid viral testing did not reduce antibiotic use in the ED significantly, neither clinically nor statistically. We found lower rates of chest radiography (RR 0.77, 95% CI 0.65 to 0.91) in the rapid viral testing group but no effect on length of ED visits, blood or urine testing in the ED.

AUTHORS' CONCLUSIONS

Current evidence is insufficient, although promising, to support routine rapid viral testing as a means to reduce antibiotic use in pediatric EDs. Results suggest that rapid viral testing may be beneficial but are not statistically significant due to lack of power. A large trial addressing these outcome measures is needed.

Respiratory virus infections

The respiratory tract is a frequent site of infection with a wide range of viruses. Each family of viruses can cause differing clinical syndromes depending on the age of the patient and the immune response. As a corollary, different clinical syndromes can be caused by different families of viruses.

A comparison of Thermo Electron RSV OIA to viral culture and direct fluorescent assay testing for respiratory syncytial virus

BACKGROUND

Rapid diagnostic methods for respiratory syncytial virus are useful tools available for the clinician.

OBJECTIVES

The Thermo Electron RSV OIA (optical immunoassay kit) was prospectively compared with direct immunofluorescent assay and viral culture at Primary Children's Medical Center, Salt Lake City, Utah.

STUDY DESIGN

Specimens from three hundred and thirty patients exhibiting respiratory symptoms were collected for testing by the three methods above. Several specimens were positive by both OIA and DFA with a negative culture result. These culture results were verified by RT-PCR analysis.

RESULTS

Overall, 107 specimens were positive for RSV by the reference tests (culture or RT-PCR). DFA analysis identified an additional 40 patient specimens positive for other respiratory viruses. Compared to the reference tests the sensitivity, specificity, positive, and negative predictive values of the OIA for detection of RSV were 87.9%, 99.6%, 98.9% and 94.5%, respectively.

CONCLUSIONS

The rapid OIA assay format proved to be cost effective, and simple to use in comparison to DFA and viral culture. Negative rapid test results should still be confirmed with a secondary test.

A comparison of Binax NOW to viral culture and direct fluorescent assay testing for respiratory syncytial virus

The Binax NOW immunochromatographic assay for respiratory syncytial virus was prospectively compared with direct fluorescent assay and viral culture at Primary Children's Medical Center, Salt Lake City, Utah during February 2003. Three hundred ten patient specimens were collected for testing, of which 102 specimens were positive for respiratory syncytial virus by the reference tests, direct immunofluorescence assay (DFA), and culture or molecular analysis. DFA analysis identified an additional 40 patient specimens positive for other respiratory viruses. Compared to the reference tests, the sensitivity, specificity, and positive and negative predictive values of the rapid immunochromatographic assay for detection of respiratory syncytial virus were 89.2%, 100.0%, 100.0%, and 94.9%, respectively. This rapid assay format proved to be cost-effective and simple to use in comparison to DFA and viral culture. Negative rapid test results should still be confirmed with a secondary test.

Indirect fluorescent antibody testing of nasopharyngeal swabs for influenza diagnosis in lung transplant recipients

BACKGROUND

Rapid and reliable diagnosis of respiratory viral infections (RVI) in lung transplant recipients is essential to direct therapy of acute graft dysfunction and identify epidemic trends. Traditional techniques of serology and viral culture are limited by the lack of antibody response and delay in diagnosis.

METHODS

We examined the clinical utility of indirect fluorescent antibody (IFA) testing in adult lung transplant patients with suspected RVI, compared with serology and culture. Nasopharyngeal and throat swabs (NT) were obtained to sample epithelial cells, followed by application of monoclonal antibody to respiratory syncytial virus, adenovirus, parainfluenza 1-3 and influenza A and B. The Bartels Respiratory Viral Detection kit was used with IFA results available within 24 hours.

RESULTS

Nine of 18 patients tested positive for RVI with influenza A (n = 8) and influenza B (n = 1) detected. The sensitivity of IFA (67%) was higher than that of cell culture (45%). With intensive supportive therapy, infection was self-limiting in bronchiolitis obliterans syndrome (BOS) Grade 0-2 patients. However, patients with BOS Grade 3 manifested an acute exacerbation of airflow obstruction, which proved to be irreversible.

CONCLUSIONS

Lung transplant patients with "flu-like" symptoms should proceed to IFA testing of NT swab specimens for early diagnosis. Samples collected within 7 days of symptom onset have high sensitivity as compared with serology and viral culture techniques.