Molecular point-of-care testing for respiratory viruses versus routine clinical care in adults with acute respiratory illness presenting to secondary care: a pragmatic randomised controlled trial protocol (ResPOC)

Epidemiology and clinical characteristics of severe acute respiratory infections among hospitalized children under 5 years of age in a tertiary care center in Bangkok, Thailand, 2019-2020

Background

Acute respiratory infections (ARIs) are common in children and can range in severity from mild self-limiting illnesses to more severe conditions such as pneumonia and respiratory failure. Data on the epidemiology of viral and bacterial pathogens causing ARIs in children are scarce in this region. This study aimed to investigate the epidemiology and clinical manifestations of pathogens in children aged ≤5 years presenting with severe acute respiratory infection (SARI) in Bangkok, Thailand. The impact of rapid multiplex PCR-based testing on clinical management is also explored.

Methods

This cross-sectional study enrolled consecutive children aged ≤5 years presenting with SARI at a tertiary care centre in Bangkok, Thailand, between 2019 and 2020. Nasopharyngeal swabs were collected once at admission, and viral and bacterial pathogens were tested using the QIAstat-Dx respiratory panel.

Results

A total of 169 children were enrolled in this study. At least one pathogenic virus was detected in 91.7 % of participants. Based on the final diagnoses made upon discharge, 30.2 % had upper respiratory tract infection, whereas 66.3 % had lower respiratory tract infection. Pneumonia was the most common diagnosis (59.2 %). The most common pathogen identified was rhino/enterovirus (45.2 %), followed by respiratory syncytial virus (31.6 %) and parainfluenza virus (14.2 %). Co-infection was found in 15.4 % and was not associated with increased disease severity.

Conclusions

This study provides additional insights into the pathogen profiles, clinical diagnosis, and co-infection combinations of ARIs in hospitalized children. This information is useful for diagnosis and treatment of ARIs, as well as implementation of appropriate infection control measures and guidance for future vaccine policy development.

The QuantuMDx Q-POC SARS-CoV-2 RT-PCR assay for rapid detection of COVID-19 at point-of-care: preliminary evaluation of a novel technology

Accurate and rapid point-of-care (PoC) diagnostics are critical to the control of the COVID-19 pandemic. The current standard for accurate diagnosis of SARS-CoV-2 is laboratory-based reverse transcription polymerase chain reaction (RT-PCR) assays. Here, a preliminary prospective performance evaluation of the QuantuMDx Q-POC SARS-CoV-2 RT-PCR assay is reported. Between November 2020 and March 2021, 49 longitudinal combined nose/throat (NT) swabs from 29 individuals hospitalised with RT-PCR confirmed COVID-19 were obtained at St George's Hospital, London. In addition, 101 mid-nasal (MN) swabs were obtained from healthy volunteers in June 2021. These samples were used to evaluate the Q-POC SARS-CoV-2 RT-PCR assay. The primary analysis was to compare the sensitivity and specificity of the Q-POC test against a reference laboratory-based RT-PCR assay. The overall sensitivity of the Q-POC test compared with the reference test was 96.88% (83.78- 99.92% CI) for a cycle threshold (Ct) cut-off value for the reference test of 35 and 80.00% (64.35-90.95% CI) without altering the reference test's Ct cut-off value of 40. The Q-POC test is a sensitive, specific and rapid PoC test for SARS-CoV-2 at a reference Ct cut-off value of 35. The Q-POC test provides an accurate option for RT-PCR at PoC without the need for sample pre-processing and laboratory handling, enabling rapid diagnosis and clinical triage in acute care and other settings.

Detection of respiratory pathogens by application of multiplex PCR panel during early period of COVID-19 pandemic in a tertiary hospital in Central Taiwan

BACKGROUND

Respiratory tract infections (RTIs) represent a major cause of clinical visits worldwide. Viral epidemiology of RTIs in adults has been less studied compared to children. FilmArray respiratory panel (FA-RP), a multiplex, real time polymerase chain reaction method can simultaneously detect the nucleic acids of multiple pathogens. The purpose of this study is to analyze the epidemiology and clinical presentations of an RTI cohort.

METHODS

This retrospective cohort study was conducted at China Medical University Hospital (CMUH) and China Medical University Children's Hospital (CMUCH), from January 2020 to June 2020. The FA-RP results were collected and analyzed according to upper versus lower RTIs.

RESULTS

Among 253 respiratory samples tested, 135 (53.4%) were from adults and 118 (46.6%) from children. A total positive rate of 33.9% (86/253) was found, with 21.48% (29/135) in adults and 48.31% (57/118) in children. Human rhinovirus/Enterovirus (HRV/EV) was detected in most of the age groups and was more common in URIs. HRV/EV was found as a frequent co-detection virus. Among children, HRV/EV was the most detected pathogen of URIs, while the most predominant pathogen in LRIs was Mycoplasma pneumoniae.

CONCLUSIONS

FA-RP has the potential to improve the detection rate of respiratory pathogens. The positive rate of FA-RP was higher in children compared to adults, which likely corresponds to the higher incidence of viral RTIs in children. Different pathogens may lead to different types of respiratory infections.

A pragmatic randomized controlled trial of rapid on-site influenza and respiratory syncytial virus PCR testing in paediatric and adult populations

Background

Rapid/point-of-care respiratory virus nucleic acid tests (NAT) may improve oseltamivir, antibiotic, diagnostic test, and hospital bed utilization. Previous randomized controlled trials (RCT) on this topic have not used standard procedures of an accredited healthcare and laboratory system.

Methods

We conducted a parallel RCT at two hospitals [paediatric = Alberta Children’s Hospital (ACH); primarily adult = Peter Lougheed Centre (PLC)]. Patients with a respiratory viral testing order were randomized to testing at either a central accredited laboratory (standard arm) or with a rapid polymerase chain reaction test at an on-site accredited laboratory followed by standard testing [rapid on-site test (ROST) arm] based on day of specimen receipt at the laboratory. Patients and clinicians were blinded to assignment.

The primary outcome for ACH was inpatient length of stay (LOS) and for PLC was the proportion of inpatients prescribed oseltamivir.

Results

706 patient encounters were included at ACH; 322 assigned to ROST (181 inpatients) and 384 to the standard arm (194 inpatients). 422 patient encounters were included at PLC; 200 assigned to ROST (157 inpatients) and 222 to the standard arm (175 inpatients).

The rate of oseltamivir prescription and number of doses given was reduced in PLC inpatients negative for influenza in the ROST arm compared to standard arm [mean 14.9% (95% CI 9.87–21.9) vs. 27.5% (21.0–35.2), p = 0.0135; mean 2.85 doses (SEM 2.39–3.32) vs. 4.17 doses (3.85–4.49) p = 0.022, respectively]. ROST also significantly reduced oseltamivir use at ACH, reduced chest radiographs (ACH), and laboratory test ordering (PLC), but not antibiotic prescriptions. ROST also reduced the median turnaround time by > 24 h (ACH and PLC).

The LOS at ACH was not significantly different between the ROST and standard arms [median 4.05 days (SEM 1.79–18.2) vs 4.89 days (2.07–22.9), p = 0.062, respectively].

No adverse events were reported.

Conclusions

In a RCT representing implementation of ROST in an accredited laboratory system, we found that a ROST improved oseltamivir utilization and is the first RCT to show reduced ancillary testing in both paediatric and adult populations. A larger study is required to assess reduction in paediatric LOS as ACH was underpowered. These findings help justify the implementation of rapid on-site respiratory virus testing for inpatients.

Trial registration ISRCTN, number 10110119, Retrospectively Registered, 01/12/2021.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-022-07796-3.

Rapid on-site molecular Point of Care Testing during influenza outbreaks in aged care facilities improves antiviral use and reduces hospitalisation

OBJECTIVE

Western Sydney Local Health District (WSLHD) measured the utility and validity of rapid molecular point-of-care testing (POCT) in aged care facilities (ACFs) experiencing influenza-like illness (ILI) outbreaks against routine laboratory testing.

METHODS

A descriptive epidemiological study into 82 respiratory outbreaks reported across 63 ACFs within WSLHD supporting approximately 6,500 residents aged ≥65 years and staffed by ∼6,500 employees, from 1 August 2018 to 31 December 2019.

RESULTS

WSLHD Public Health Unit performed on-site testing at 27 ACF outbreaks (34%), while 53(66%) ACFs conducted only routine laboratory testing. The Xpert®Xpress Flu/RSV molecular PCR provided a sensitivity and specificity of 100%. Those with on-site testing, antiviral prophylaxis was prescribed at 75% of facilities within 24 hours of testing, as opposed to 32% of those using laboratory testing (p<0.01). There were 24 of 181 ACF residents hospitalised in the POCT group compared to 76 of 357 in the laboratory-only group (OR=0.57; p=0.02).

CONCLUSIONS

On-site ACF testing is reliable and practical for early identification of influenza, enabling timely use of antiviral treatment and prophylaxis, and was associated with decreased hospitalisation.

PUBLIC HEALTH IMPLICATIONS

Enhanced respiratory surveillance and on-site testing should be strongly considered as part of routine management of respiratory outbreaks in ACFs and may reduce outbreak severity.

Performance- and cost-benefit analysis of an influenza point-of-care test compared to laboratory-based multiplex RT-PCR in the emergency department

INTRODUCTION

Influenza poses a heavy burden on emergency departments (ED) and hospital wards. Fast and reliable bedside tests are invaluable in obtaining indications for (cohort) droplet isolation precautions and improving patient flow. We performed a cost-benefit analysis comparing influenza point-of-care testing (POCT) to laboratory-based multiplex ligation-dependent probe amplification.

METHODS

Data of 275 ED presentations between January-April 2019 were analyzed. Patients received both POCT and MLPA to calculate POCT sensitivity and specificity. Costs were calculated for both a POCT and MLPA scenario, including costs for testing, admission, droplet isolation precautions and cleaning.

RESULTS

In our study population, 34 patients (12%) were identified with influenza A. No cases of influenza B were identified. Mean age of the influenza positive patients was 75(18) years and 56% were male. The most common symptoms upon presentation were cough, malaise and fever, with 74%, 56% and 50%, respectively. Compared to MLPA, POCT yielded a sensitivity of 94%, a specificity of 98% and a negative predictive value of 99% for influenza A. Using POCT yielded a cost reduction of €93,26 per patient.

CONCLUSIONS

Influenza POCT is an accurate and cost-beneficial method to differentiate between admission with or without droplet isolation precautions. It can be useful in clinical decision making and reducing pressure on ED and hospital beds in an influenza peak season, by enabling fast patient flow and cohort isolation.

Diagnostic Tests Can Stem the Threat of Antimicrobial Resistance: Infectious Disease Professionals Can Help

Uptake of existing diagnostics to identify infections more accurately could minimize unnecessary antibiotic use and decrease the growing threat of antibiotic resistance. The Infectious Diseases Society of America (IDSA) and the Presidential Advisory Council on Combating Antibiotic-Resistant Bacteria (PACCARB) agree that, to improve uptake of existing diagnostics, healthcare providers, health systems, and payors all need better clinical and economic outcomes data to support use of diagnostic tests over empiric use of antibiotics, providers need better tools and education about diagnostic tests, and diagnostics developers need federal funding in the absence of a viable diagnostics market. Recommendations from PACCARB and the IDSA are amplified. Incentives for-and challenges to-diagnostics research, development, and uptake are summarized. Advocacy opportunities are given for infectious disease professionals to join the fight against antimicrobial resistance.

Current Status of Clinical Application of Point-of-Care Testing

CONTEXT.—

The clinical applications of point-of-care testing (POCT) are gradually increasing in many health care systems. Recently, POCT devices using molecular genetic method techniques have been developed. We need to examine clinical pathways to see where POCT can be applied to improve them.

OBJECTIVE.—

To introduce up-to-date POCT items and equipment and to provide the content that should be prepared for clinical application of POCT.

DATA SOURCES.—

Literature review based on PubMed searches containing the terms point-of-care testing, clinical chemistry, diagnostic hematology, and clinical microbiology.

CONCLUSIONS.—

If medical resources are limited, POCT can help clinicians make quick medical decisions. As POCT technology improves and menus expand, areas where POCT can be applied will also increase. We need to understand the limitations of POCT so that it can be optimally used to improve patient management.

Update in Viral Infections in the Intensive Care Unit

The advent of highly sensitive molecular diagnostic techniques has improved our ability to detect viral pathogens leading to severe and often fatal infections that require admission to the Intensive Care Unit (ICU). Viral infections in the ICU have pleomorphic clinical presentations including pneumonia, acute respiratory distress syndrome, respiratory failure, central or peripheral nervous system manifestations, and viral-induced shock. Besides de novo infections, certain viruses fall into latency and can be reactivated in both immunosuppressed and immunocompetent critically ill patients. Depending on the viral strain, transmission occurs either directly through contact with infectious materials and large droplets, or indirectly through suspended air particles (airborne transmission of droplet nuclei). Many viruses can efficiently spread within hospital environment leading to in-hospital outbreaks, sometimes with high rates of mortality and morbidity, thus infection control measures are of paramount importance. Despite the advances in detecting viral pathogens, limited progress has been made in antiviral treatments, contributing to unexpectedly high rates of unfavorable outcomes. Herein, we review the most updated data on epidemiology, common clinical features, diagnosis, pathogenesis, treatment and prevention of severe community- and hospital-acquired viral infections in the ICU settings.

Impact of BioFire FilmArray respiratory panel results on antibiotic days of therapy in different clinical settings

Objective:

The BioFire FilmArray Respiratory Panel (RFA) has been proposed as a tool that can aid in the timely diagnosis and treatment of respiratory tract infections but its effect on antibiotic prescribing among adult patients has varied. We evaluated the impact of RFA result on antibiotic days of therapy (DOTs) in 2 distinct cohorts: hospitalized patients and patients discharged from the emergency department (ED).

Design:

Retrospective cohort study.

Setting:

The study was conducted in 3 community hospitals in Des Moines, Iowa, from March 3 to March 16, 2019.

Patients:

Adults aged >18 years.

Methods:

Potential outcome means and average treatment effects for RFA results on antibiotic DOTs were estimated. Inverse probability of treatment weighting with regression adjustment was used.

Results:

We identified 243 patients each in the hospitalized and ED-discharged cohorts. Among hospitalized patients, RFA results did not affect antibiotic DOTs. Among patients discharged from the ED, we found that if all patients had had influenza detected, the average DOTs would have been 2.3 DOTs (−3.2 to −1.4) less than the average observed if all the patients had had a negative RFA (P < .0001); no differences in DOTs were observed when comparing an RFA with a noninfluenza virus detected compared to an RFA with negative results.

Conclusions:

The impact of RFA results on antibiotic DOTs varies by clinical setting, and reductions were observed only among patients discharged from the ED who had influenza A or B detected.

Field applicable detection of hepatitis B virus using internal controlled duplex recombinase-aided amplification assay and lateral flow dipstick assay

Hepatitis B virus (HBV) is a widespread blood-borne pathogen associated with the complication of liver cirrhosis and hepatocellular carcinoma, particularly in south-east Asian and African countries where HBV is highly endemic and the budget and resources are limited. Therefore, simple, rapid, and portable field detection methods are crucial to efficiently control HBV infection. In this study, using heat-treated DNA, we developed two-field applicable detection assays for HBV based on recombinase-aided amplification (RAA). One was an internal controlled duplex RAA assay using a portable real-time fluorescence detection device, another was an instrument-free visual observation assay using lateral flow dipsticks. The entire experimental time was greatly shortened to less than 40 minutes at 39.0°C. The sensitivities, specificities, and clinical performance of both assays were evaluated. Compared with quantitative polymerase chain reaction assay as a reference, our results demonstrated that the two RAA-based assay obtained 97.18% and 95.77% of sensitivity, respectively, and the specificity was 100%, by testing a total of 157 serum samples with HBsAg positive. We conclude that the advantages of rapidity, simplicity, portability, and visualization of proposed two assays make them great potentials in point-of-care testing of HBV infection by untrained people in resource-limited situations.

SARS-CoV-2 has displaced other seasonal respiratory viruses: Results from a prospective cohort study

•

The incidence of other respiratory viruses fell dramatically during the first peak.

•

SARS-CoV-2 was rarely co-detected with other respiratory viruses.

•

SARS-CoV-2 was infrequently associated with exacerbations of COPD or asthma.

•

Mortality rate was much higher in patients with COVID-19 compared to other viruses.

Objectives

The effect of SARS-CoV-2 on existing respiratory viruses in circulation and the overall burden of viral respiratory disease remains uncertain. Traditionally, severe viral respiratory disease disproportionally affects those with underlying chronic lung diseases. This study aimed to assess the impact of SARS-CoV-2 on the prevalence and clinical characteristics of respiratory virus disease in hospitalised adults.

Methods

Data for this cohort study were from hospitalised adults who had multiplex PCR testing for respiratory viruses over several seasons in Hampshire, UK. Respiratory virus detection during the first epidemic peak of SARS-CoV-2 was compared to detection during the same time period across previous years.

Results

856 patients had multiplex PCR for respiratory viruses between March and May over 5 years. Before 2020, a non-SARS-CoV-2 virus was detected in 54% patients (202/371) compared to 4.1% (20/485) in 2020 (p < 0.0001). SARS-CoV-2 was associated with asthma or COPD exacerbations in a smaller proportion of infected patients compared to other viruses (1.0% vs 37%, p < 0.0001).

Conclusions

The emergence of SARS-CoV-2 was associated with substantial reductions in the circulation of seasonal respiratory viruses and large differences in the characteristics of viral-associated disease, including illness in a greater proportion of patients without underlying lung disease.

The experience of point-of-care testing for influenza in Scotland in 2017/18 and 2018/19 – no gain without pain

Background

During the 2017/18 and 2018/19 influenza seasons, molecular amplification-based point-of-care tests (mPOCT) were introduced in Scotland to aid triaging respiratory patients for hospital admission, yet communication of results to national surveillance was unaccounted for.

Aim

This retrospective study aims to describe steps taken to capture mPOCT data and assess impact on influenza surveillance.

Methods

Questionnaires determined mPOCT usage in 2017/18 and 2018/19. Searches of the Electronic Communication of Surveillance in Scotland (ECOSS) database were performed and compared with information stored in laboratory information management systems. Effect of incomplete data on surveillance was determined by comparing routine against enhanced data and assessing changes in influenza activity levels determined by the moving epidemic method.

Results

The number of areas employing mPOCT increased over the two seasons (6/14 in 2017/18 and 8/14 in 2018/19). Analysis of a small number of areas (n = 3) showed capture of positive mPOCT results in ECOSS improved between seasons and remained high (> 94%). However, capture of negative results was incomplete. Despite small discrepancies in weekly activity assessments, routine data were able to identify trend, start, peak and end of both influenza seasons.

Conclusion

This study has shown an improvement in capture of data from influenza mPOCT and has highlighted issues that need to be addressed for results to be accurately captured in national surveillance. With the clear benefit to patient management we suggest careful consideration should be given to the connectivity aspects of the technology in order to ensure minimal impact on national surveillance.

Repeat Molecular Testing for Respiratory Pathogens: Diagnostic Gain or Diminishing Returns?

BACKGROUND

Upper respiratory tract infections are common, and the ability to accurately and rapidly diagnose the causative pathogen has important implications for patient management.

METHODS

We evaluated the test-ordering practices for 2 commonly utilized nucleic acid amplification tests (NAATs) for the detection of respiratory pathogens: the Xpert Flu Assay for influenza A/B (Flu assay) and the Biofire FilmArray respiratory panel assay (RP assay), which detects 20 different targets. Our study examined repeat testing; that is, testing within 7 days from an initial test.

RESULTS

Our study found that repeat testing is common for each of the individual assays: 3.0% of all Flu assays and 10.0% of all RP assays were repeat testing. Of repeat testing, 8/293 (2.7%) of repeat Flu assays and 75/1257 (6.0%) of RP assays resulted diagnostic gains, i.e., new detections. However, for the RP assay, these new detections were not always clinically actionable. The most frequently discrepant organisms were rhinovirus/enterovirus (28/102, 27.5%), followed by respiratory syncytial virus (12/102, 11.8%) and coronavirus OC43 (11/102, 10.8%). Furthermore, there were 3,336 instances in which a patient was tested using both a Flu assay and RP assay, of which only 44 (1.3%) had discrepant influenza results.

CONCLUSIONS

Our findings suggest opportunities exist to better guide ordering practices for respiratory pathogen testing, including limiting repeat testing, with the goal of optimization of clinical yield, and diagnostic stewardship.

Multiplex Tests for Respiratory Tract Infections: The Direct Utility of the FilmArray Respiratory Panel in Emergency Department

Background

The FilmArray Respiratory Panel with multiplex targets for respiratory pathogens has been widely used and verified in clinical trials in special test settings. However, it is necessary to evaluate the panel's performance at the point of care directly, in nonspecific test settings.

Methods

Patients with respiratory tract infections were enrolled from among emergency department visitors, and all steps, including the collection of specimens and testing, were performed by our clinicians.

Results

Among 270 patients, 196 (72.6%) patients were found to have one or more pathogens. For signal pathogen detection, influenza A virus had the highest rate of detection; 45 (16.7%) of the patients had two or more respiratory pathogens codetected, and most of the multiplex pathogens were rhinovirus/enterovirus codetected with Bordetella pertussis (17.8%). The information provided by the FilmArray had an impact on the prescription of antimicrobials, and there were differences in the rates of antibiotic prescriptions and anti-influenza prescriptions among patients.

Conclusions

Use of the FilmArray by clinical staff was successfully implemented in the emergency department for the first time in China. The FilmArray has the potential for point-of-care testing in nonspecific settings.

Rapid and Point-of-Care Testing in Respiratory Tract Infections: An Antibiotic Guardian?

This is a narrative review on the potential of rapid and point-of-care microbiological testing in pneumonia patients, focusing particularly on hospital-acquired and ventilator-associated pneumonia, which have substantial mortality and diverse microbiology. This work is written from a United Kingdom perspective, but much of it is generalizable internationally. In a world where antimicrobial resistance is a major international threat, the use of rapid molecular diagnostics has great potential to improve both the management of pneumonia patients and the stewardship of antibiotics. Rapid tests potentially can distinguish patients with bacterial versus viral infection and can swiftly identify bacterial pathogens and their resistances. We seek to answer the question: “Can such tests be used as an antibiotic guardian?” Their availability at the bedside rather than in the laboratory should best ensure that results are swiftly used to optimize patient management but will raise new challenges, not the least with respect to maintaining quality control and microbiology/infection control input. A further challenge lies in assessing the degree of trust that treating clinicians will place in these molecular diagnostic tests, particularly when early de-escalation of antibiotic therapy is indicated.

Impact of point-of-care testing for respiratory viruses on antibiotic use in adults with exacerbation of airways disease

BACKGROUND

The ResPOC study demonstrated that syndromic molecular point-of-care testing (POCT) for respiratory viruses was associated with early discontinuation of unnecessary antibiotics compared to routine clinical care. Subgroup analysis suggests these changes occur predominantly in patients with exacerbation of airways disease. Use of molecular POCT for respiratory viruses is becoming widespread but there is a lack of evidence to inform the choice between multiplex syndromic panels versus POCT for influenza only.

MATERIALS/METHODS

We evaluated patients from the ResPOC study with exacerbation of asthma or COPD who were treated with antibiotics. The duration of antibiotics and proportion with early discontinuation were compared between patients testing positive and negative for viruses by POCT, and controls. Patients testing positive for viruses by POCT were compared according to virus types.

RESULTS

118 patient with exacerbation of airways disease received antibiotics in the POCT group and 111 in the control group. In the POCT group 49/118 (42%) patients tested positive for viruses. Of those testing positive for viruses 17/49 (35%) had early discontinuation of antibiotics versus 9/69 (13%) testing negative and 7/111 (6%) of controls, p<0.0001. Of those positive for viruses by POCT 10/49 (20%) were positive for influenza, 21/49 (43%) for rhinovirus and 18/49 (37%) for other viruses. The proportion with early discontinuation of antibiotics was not different between the virus types (p = 0.34).

CONCLUSIONS

This data suggests that syndromic molecular POCT for respiratory viruses should be favoured over POCT for influenza alone in adults with exacerbation of airways disease.

Hospitalised adults with pneumonia are frequently misclassified as another diagnosis

Using data from a large randomised controlled trial of adults hospitalised with acute respiratory illness, we examined the reliability of pneumonia diagnosis on discharge documentation. 50 (28.2%) of 177 patients with a pneumonia diagnosis had no radiological evidence of pneumonia. 67 (34.9%) of 192 patients with clinico-radiological evidence of pneumonia did not have a diagnosis of pneumonia listed; 'COPD exacerbation' or 'lower respiratory tract infection' was often listed instead. These patients more frequently had a respiratory comorbidity and lower oxygen saturations, CRP and temperature at presentation. Pneumonia diagnoses misclassification on discharge documentation may have clinical, financial, and research data implications.

Future management of viral diseases: role of new technologies and new approaches in microbial interactions

BACKGROUND

New technologies allow rapid detecting and counting of virus genomes in clinical specimens, defining susceptibility to specific antivirals, pinpointing molecular sequences correlated to virulence traits, and identifying viral and host factors driving resolution or chronicity of infections. As a result, during the past three decades the diagnostic virology laboratory has become crucial for patient care and an integral component of the multifarious armamentarium for patient management. This change in paradigm has caused obsolescence of methods once considered the reference standard of infectious disease diagnosis that were used to detect whole or specific components of virions in the specimen.

OBJECTIVES

This review provides an overview of standard and novel technologies applied to molecular diagnosis of viral infections and illustrates some crucial points for correcting interpretation of the laboratory data.

SOURCES

Peer-reviewed literature of topics pertinent to this review.

CONTENT AND IMPLICATIONS

New technologies are reinventing the way virologic diagnoses are made, with a conversion to new, simpler-to-use platforms. Although indicated for the same purpose, not all methods are equal and can yield different results. Further, tests identifying multiple analytes at once can detect microorganisms present or activated as a result of pathologic processes triggered by other pathogens or noninfectious causes. Thus, new directions will have to be taken in the way in which the diagnoses of viral diseases are performed. This represents a breakthrough in the clinical virology laboratory.

Can point-of-care testing shorten hospitalization length of stay? An exploratory investigation of infectious agents using regression modelling

This retrospective study investigates the potential benefits from the introduction of point-of-care tests for rapid diagnosis of infectious diseases. We analysed a sample of 441 hospitalized patients who had received a final diagnosis related to 18 pathogenic agents. These pathogens were mostly detected by standard tests but were also detectable by point-of-care testing. The length of hospital stay was partitioned into pre- and post-laboratory diagnosis stages. Regression analysis and elementary queueing theory were applied to estimate the impact of quick diagnosis on the mean length of stay and the utilization of healthcare resources. The analysis suggests that eliminating the pre-diagnosis times through point-of-care testing could shorten the mean length of hospital stay for infectious diseases by up to 34 per cent and result in an equal reduction in bed occupancy and other resources. Regression and other more sophisticated models can aid the financing decision-making of pilot point-of-care laboratories in healthcare systems.

Impact of Nasopharyngeal FilmArray Respiratory Panel Results on Antimicrobial Decisions in Hospitalized Patients

Objective

To determine whether results of the nasopharyngeal FilmArray respiratory panel (NP-FARP) influenced antibiotic decisions.

Methods

We reviewed the medical records of nonintensive care unit (ICU) inpatients that had an NP-FARP performed at our institution between June 2013 and June 2014. The inpatient records were reviewed 48 hours after the NP-FARP for the following data: demographic information; NP-FARP, serum procalcitonin, and methicillin-resistant Staphylococcus aureus nasal swab (MRSA NS) results; antibiotics prior and post-48 hours of the NP-FARP result; and the current immunosuppression status. Clinical outcome data were not obtained. Patients were categorized into those who had a positive (+) or a negative (-) NP-FARP. We further subdivided these two categories into groups A, B, and C based on the antibiotic modifications 48 hours after their NP-FARP result. Group A included patients who were never initiated on antimicrobial therapy. Patients whose antibiotics were discontinued or deescalated were placed in group B. Patients with antibiotic escalation or continuation without change constituted group C. We compared and analyzed groups A, B, and C in the (+) and (-) NP-FARP cohorts.

Results

A total of 545 patients were included. There were 143 (26%) patients with positive and 402 (74%) patients with negative NP-FARPs. Comparison of groups A, B, and C between those with a (+) and (-) NP-FARP were as follows: (+) A and (-) A, 28/143 (20%) and 84/402 (21%); (+) B and (-) B, 59/143 (41%) and 147/402 (37%); and (+) C and (-) C, 56/143 (39%) and 171/402 (43%), respectively. We found no statistically significant differences between groups (+) A versus (-) A, (+) B versus (-) B, and (+) C versus (-) C with respect to age, gender, MRSA NS result, procalcitonin result, or concurrent immunosuppression.

Conclusion

In non-ICU inpatients, NP-FARP alone or in combination with procalcitonin or MRSA NS did not influence antibiotic decisions during the study period.

Age-related prevalence of common upper respiratory pathogens, based on the application of the FilmArray Respiratory panel in a tertiary hospital in Greece

The FilmArray Respiratory Panel (FA-RP) is an FDA certified multiplex PCR that can detect 17 viruses and 3 bacteria responsible for upper respiratory tract infections, thus it is potentially useful to the assessment of the age-related prevalence of these pathogens.In this observational study, we retrospectively analyzed the results of all the respiratory samples, which had been processed during 1 year-period (November 2015 to November 2016) with the FA-RP, in the Central Laboratories of Hygeia & Mitera General Hospitals of Athens, Greece. In order to have an age-related distribution, the following age groups were implemented: (<2), (≥2, <5), (≥5, <10), (≥10, <18), (≥18, <45), (≥45, <65), and (≥65) years old.Among 656 respiratory samples tested, 362 (55%) were from male and 294 (45%) from female patients, while 356 (54.3%) were positive and 300 (45.7%) negative. In the first age-group (<2), 41/121 samples (33.9%) revealed human rhinovirus/enterovirus (HRV) and 16 (13.2%) adenovirus (Adv), followed by respiratory syncytial virus (RSV), coronavirus, human metapneumovirus (Hmpv), and parainfluenza viruses (PIV). In the age-group (≥2, <5), Adv predominated with 37/147 samples (25.2%), followed by HRV, RSV, coronavirus (all types), and influenza, Hmpv and PIV. In the age-group (≥5, <10), HRV was identified in 25/80 samples (31.3%), Adv in 18 (22.5%), influenza in 11 (13.8%), and Hmpv in 6 (7.5%). Influenza predominated in the age-group (≥10, <18), with 4/22 samples (18.2%), while in the remaining age-groups (≥18), HRV was the commonest isolated pathogen, 33/286 (11.5%), followed by influenza with 20 (7%) (influenza A H1-2009, 11/20).In our patient series, HRV seemed to prevail in most age-groups, followed by Adv, although Influenza was the second most frequent pathogen isolated in the age-groups (≥18). Moreover, increasing age corresponded to increasing possibility of having a negative sample, indicating that FilmArray may be more useful before adolescence.