Retrospective Evaluation of Infants Aged 1 to 60 Days with Residual Cerebrospinal Fluid (CSF) Tested Using the FilmArray Meningitis/Encephalitis (ME) Panel

Distinguishing community-acquired bacterial and viral meningitis: Microbes and biomarkers

Diagnostic tools to differentiate between community-acquired bacterial and viral meningitis are essential to target the potentially lifesaving antibiotic treatment to those at greatest risk and concurrently spare patients with viral meningitis from the disadvantages of antibiotics. In addition, excluding bacterial meningitis and thus decreasing antibiotic consumption would be important to help reduce antimicrobial resistance and healthcare expenses. The available diagnostic laboratory tests for differentiating bacterial and viral meningitis can be divided microbiological pathogen-focussed methods and biomarkers of the host response. Bacterial culture-independent microbiological methods, such as highly multiplexed nucleic acid amplification tests, are rapidly making their way into the clinical practice. At the same time, more conventional host protein biomarkers, such as procalcitonin and C-reactive protein, are supplemented by newer proteomic and transcriptomic signatures. This review aims to summarise the current state and the recent advances in diagnostic methods to differentiate bacterial from viral meningitis.

Relevance of enteroviruses in neonatal meningitis

INTRODUCTION

Enterovirus (EV) infections are the most frequent infections in the neonatal period and in many cases lead to hospital admission of the newborn (NB). The aim of this study was to determine the incidence of EV in the etiology of neonatal meningitis and to define the clinical characteristics of newborns with EV meningitis.

MATERIAL AND METHOD

Retrospective observational cohort study. Including 91 NBs with meningitis and gestational age greater than 34 weeks gestational age (GA) attended in our center over a period of 16 years.

RESULTS

The percentage of NBs with EV meningitis was higher than that of NBs with bacterial meningitis (BM) and accounted for 78% (n=71). Half of the NBs with EV infection had a history of epidemic environment among their caregivers. Fever was present in 96% of cases as a clinical sign and, in general, sensory disturbances represented the main neurological alterations. Antibiotics (ATB) were given to 71.4% of patients with EV infection. Detection of EV in CSF samples showed a high sensitivity for the diagnosis of EV meningitis. The most frequently implicated EV types were echovirus 11, coxsackievirus B5, echovirus 18, 25 and 7.

CONCLUSIONS

The results of this series show that enterovirus infection is a common cause of neonatal meningitis. These data underline the importance of rapid EV testing of infants with suspected meningitis. This allows early diagnosis and reduces antibiotic treatment, hospitalization time and related costs.

Decoding human cytomegalovirus for the development of innovative diagnostics to detect congenital infection

Cytomegalovirus is the most common cause of congenital infectious disease and the leading nongenetic etiology of sensorineural hearing loss. Although most infected neonates are asymptomatic at birth, congenital cytomegalovirus infection is responsible for nearly 400 infant deaths annually in the United States and may lead to significant long-term neurodevelopmental impairments in survivors. The resulting financial and social burdens of congenital cytomegalovirus infection have led many medical centers to initiate targeted testing after birth, with a growing advocacy to advance universal newborn screening. While no cures or vaccines are currently available to eliminate or prevent cytomegalovirus infection, much has been learned over the last five years regarding disease pathophysiology and viral replication cycles that may enable the development of innovative diagnostics and therapeutics. This Review will detail our current understanding of congenital cytomegalovirus infection, while focusing our discussion on routine and emerging diagnostics for viral detection, quantification, and long-term prognostication. IMPACT: This review highlights our current understanding of the fetal transmission of human cytomegalovirus. It details clinical signs and physical findings of congenital cytomegalovirus infection. This submission discusses currently available cytomegalovirus diagnostics and introduces emerging platforms that promise improved sensitivity, specificity, limit of detection, viral quantification, detection of genomic antiviral resistance, and infection staging (primary, latency, reactivation, reinfection).

Exploring the Utility of Multiplex Infectious Disease Panel Testing for Diagnosis of Infection in Different Body Sites: A Joint Report of the Association for Molecular Pathology, American Society for Microbiology, Infectious Diseases Society of America, and Pan American Society for Clinical Virology

The use of clinical molecular diagnostic methods for detecting microbial pathogens continues to expand and, in some cases, supplant conventional identification methods in various scenarios. Analytical and clinical benefits of multiplex molecular panels for the detection of respiratory pathogens have been demonstrated in various studies. The use of these panels in managing different patient populations has been incorporated into clinical guidance documents. The Association for Molecular Pathology's Infectious Diseases Multiplex Working Group conducted a review of the current benefits and challenges to using multiplex PCR for the detection of pathogens from gastrointestinal tract, central nervous system, lower respiratory tract, and joint specimens. The Working Group also discusses future directions and novel approaches to detection of pathogens in alternate specimen types, and outlines challenges associated with implementation of these multiplex PCR panels.

Multiplex detection of meningitis and encephalitis pathogens: A study from laboratory to clinic

Introduction

Infectious meningitis and encephalitis (ME) are life-threatening conditions are caused by various pathogens. Conventional laboratory tests with low sensitivity and specificity cannot help with early diagnosis.

Methods

A prospective study using the novel multiplex PCR detection for 18 pathogens of ME (MME-18) was conducted to investigate the clinical utilization and the epidemiology characteristics of ME in southwestern China. Patients with suspected intracranial infection were recruited between May and October 2019 at West China Hospital of Sichuan University. The MME-18 was used to detect cerebrospinal fluid, and conventional experiments including cryptococcal capsular antigen detection, GeneXpert, real-time PCR, and clinical feedback were used to verify the result of MME-18.

Results

Among 581 tested patients, 139 eligible individuals were enrolled in the study. Among them, Mycobacterium tuberculosis was the most common pathogen in mono-infection. Viruses and Cryptococcus neoformans were also frequently detected. Of 139 infected patients, 12 cases were diagnosed by MME-18 only, 57 patients by conventional testing only, and 70 cases by both comparator tests and MME-18. There were 96.3% (79/82) diagnoses made by MME-18 had a favorable outcome, and two of twelve diagnoses, made solely by MME-18, had a likely unclear clinical significance.

Discussion

The MME-18 showed satisfactory consistency with expert clinical consensus for patients presenting with ME. Combined with conventional testing and clinical suspicion, MME-18 may help clinicians with the early identification of pathogens.

Impact of CSF Meningitis and Encephalitis Panel on Resource Use for Febrile Well-Appearing Infants

OBJECTIVES

To determine whether the BioFire FilmArray Meningitis/Encephalitis (ME) panel is associated with decreased resource use for febrile infants. The ME panel has a rapid turnaround time (1-2 hours) and may shorten length of stay (LOS) and antimicrobial use for febrile well-appearing infants.

METHODS

Retrospective cohort study of febrile well-appearing infants ≤60 days with cerebrospinal fluid culture sent in the emergency department from July 2017 to April 2019. We examined the frequency of ME panel use and its relationship with hospital LOS and initiation and duration of antibiotics and acyclovir. We used nonparametric tests to compare median durations.

RESULTS

The ME panel was performed for 85 (36%) of 237 infants. There was no difference in median hospital LOS for infants with versus without ME panel testing (42 hours, interquartile range [IQR] 36-52 vs 40 hours, IQR: 35-47, P = .09). More than 97% of infants with and without ME panel testing were initiated on antibiotics. Patients with ME panel were more likely to receive acyclovir (33% vs 18%; odds ratio: 2.2, 95%: confidence interval 1.2-4.0). There was no difference in median acyclovir duration with or without ME panel testing (1 hour, IQR: 1-7 vs 4.2 hours, IQR: 1-21, P = .10). When adjusting for potential covariates, these findings persisted.

CONCLUSIONS

ME panel use was not associated with differences in hospital LOS, antibiotic initiation, or acyclovir duration in febrile well-appearing infants. ME panel testing was associated with acyclovir initiation.

Serious Bacterial Infections in Young Febrile Infants With Positive Urinalysis Results

It is unknown whether febrile infants 29 to 60 days old with positive urinalysis results require routine lumbar punctures for evaluation of bacterial meningitis.

OBJECTIVE

To determine the prevalence of bacteremia and/or bacterial meningitis in febrile infants ≤60 days of age with positive urinalysis (UA) results.

METHODS

Secondary analysis of a prospective observational study of noncritical febrile infants ≤60 days between 2011 and 2019 conducted in the Pediatric Emergency Care Applied Research Network emergency departments. Participants had temperatures ≥38°C and were evaluated with blood cultures and had UAs available for analysis. We report the prevalence of bacteremia and bacterial meningitis in those with and without positive UA results.

RESULTS

Among 7180 infants, 1090 (15.2%) had positive UA results. The risk of bacteremia was higher in those with positive versus negative UA results (63/1090 [5.8%] vs 69/6090 [1.1%], difference 4.7% [3.3% to 6.1%]). There was no difference in the prevalence of bacterial meningitis in infants ≤28 days of age with positive versus negative UA results (∼1% in both groups). However, among 697 infants aged 29 to 60 days with positive UA results, there were no cases of bacterial meningitis in comparison to 9 of 4153 with negative UA results (0.2%, difference -0.2% [-0.4% to -0.1%]). In addition, there were no cases of bacteremia and/or bacterial meningitis in the 148 infants ≤60 days of age with positive UA results who had the Pediatric Emergency Care Applied Research Network low-risk blood thresholds of absolute neutrophil count <4 × 103 cells/mm3 and procalcitonin <0.5 ng/mL.

CONCLUSIONS

Among noncritical febrile infants ≤60 days of age with positive UA results, there were no cases of bacterial meningitis in those aged 29 to 60 days and no cases of bacteremia and/or bacterial meningitis in any low-risk infants based on low-risk blood thresholds in both months of life. These findings can guide lumbar puncture use and other clinical decision making.

Etiological Analysis of Viral Encephalitis in Children in Zhejiang Province from 2018 to 2019

Objective: To investigate the common pathogens of viral encephalitis (VE) in children, and to provide guidance for the empirical diagnosis and treatment of patients with VE. Methods: A total of 227 cerebrospinal fluid (CSF) samples were collected from pediatric patients with VE in Zhejiang province from January 2018 to December 2019. The samples were tested using multiplex and singleplex Reverse Transcription-Polymerase Chain Reaction (RT-PCR) with primers specific to enterovirus (EV), varicella-zoster virus (VZV), mumps virus (MuV), cytomegalovirus (CMV), herpes simplex virus type 1 (HSV-1)/type 2 (HSV-2), Epstein–Barr virus (EBV), and human herpesvirus 6 (HHV-6). The data of the two analyses were compared and then verified using Sanger sequencing. Results: Of the 227 CSF samples, 90 were shown to be positive for multiplex RT-PCR with a positivity rate of 39.65% and a 95% confidence interval (33.2%, 46.1%). EV was the most common cause of VE, followed by EBV, HHV-6, MuV, CMV, VZV, and HSV-1. Most included cases occurred in summer, accounting for 49.78% of all cases. For EV, EBV, and HSV-2, multiplex RT-PCR showed a positivity rate of 34.36%, which was not statistically different from that of 30.4% shown by singleplex RT-PCR. The sequences of EV, EBV, VZV, MuV, CMV, HSV-1, HHV-6, and HSV-2 were confirmed by sequencing the PCR products obtained from multiplex and singleplex PCR. Conclusions: In children, VE is more prevalent in the summer than in other seasons in Zhejiang province, and EV may be the most common causative pathogen.

Clinical and Financial Impact of a Diagnostic Stewardship Program for Children with Suspected Central Nervous System Infection

OBJECTIVE

To investigate the optimal implementation and clinical and financial impacts of the FilmArray Meningitis Encephalitis Panel (MEP) multiplex polymerase chain reaction testing of cerebrospinal fluid (CSF) in children with suspected central nervous system infection.

STUDY DESIGN

A pre-post quasiexperimental cohort study to investigate the impact of implementing MEP using a rapid CSF diagnostic stewardship program was conducted at Children's Hospital Colorado (CHCO). MEP was implemented with electronic medical record indication selection to guide testing to children meeting approved use criteria: infants <2 months, immunocompromised, encephalitis, and ≥5 white blood cells/μL of CSF. Positive results were communicated with antimicrobial stewardship real-time decision support. All cases with CSF obtained by lumbar puncture sent to the CHCO microbiology laboratory meeting any of the 4 aforementioned criteria were included with preimplementation controls (2015-2016) compared with postimplementation cases (2017-2018). Primary outcome was time-to-optimal antimicrobials compared using log-rank test with Kaplan-Meier analysis.

RESULTS

Time-to-optimal antimicrobials decreased from 28 hours among 1124 preimplementation controls to 18 hours (P < .0001) among 1127 postimplementation cases (72% with MEP testing conducted). Postimplementation, time-to-positive CSF results was faster (4.8 vs 9.6 hours, P < .0001), intravenous antimicrobial duration was shorter (24 vs 36 hours, P = .004), with infectious neurologic diagnoses more frequently identified (15% vs 10%, P = .03). There were no differences in time-to-effective antimicrobials, hospital admissions, antimicrobial starts, or length of stay. Costs of microbiologic testing increased, but total hospital costs were unchanged.

CONCLUSIONS

Implementation of MEP with a rapid central nervous system diagnostic stewardship program improved antimicrobial use with faster results shortening empiric therapy. Routine MEP testing for high-yield indications enables antimicrobial optimization with unchanged overall costs.

Group B Streptococcal Neonatal Meningitis

Neonatal bacterial meningitis is a devastating disease, associated with high mortality and neurological disability, in both developed and developing countries. Streptococcus agalactiae, commonly referred to as group B Streptococcus (GBS), remains the most common bacterial cause of meningitis among infants younger than 90 days. Maternal colonization with GBS in the gastrointestinal and/or genitourinary tracts is the primary risk factor for neonatal invasive disease. Despite prophylactic intrapartum antibiotic administration to colonized women and improved neonatal intensive care, the incidence and morbidity associated with GBS meningitis have not declined since the 1970s. Among meningitis survivors, a significant number suffer from complex neurological or neuropsychiatric sequelae, implying that the pathophysiology and pathogenic mechanisms leading to brain injury and devastating outcomes are not yet fully understood. It is imperative to develop new therapeutic and neuroprotective approaches aiming at protecting the developing brain. In this review, we provide updated clinical information regarding the understanding of neonatal GBS meningitis, including epidemiology, diagnosis, management, and human evidence of the disease's underlying mechanisms. Finally, we explore the experimental models used to study GBS meningitis and discuss their clinical and physiologic relevance to the complexities of human disease.

Differential Performance of the FilmArray Meningitis/Encephalitis Assay To Detect Bacterial and Viral Pathogens in Both Pediatric and Adult Populations

Meningitis/encephalitis (ME) syndromic diagnostic assays can be applied for the rapid one-step detection of the most common pathogens in cerebrospinal fluid (CSF). However, the comprehensive performance of multiplex assays is still under evaluation. In our multisite university hospital of eastern Paris, France, ME syndromic testing has been gradually implemented since 2017 for patients with neurological symptoms presenting to an adult or pediatric emergency unit. We analyzed the results from the BioFire FilmArray ME panel versus standard routine bacteriology and virology techniques, together with CSF cytology and clinical data, over a 2.5-year period to compare the diagnostic accuracy of the FilmArray ME panel to that of the reference methods. In total, 1,744 CSF samples from 1,334 pediatric and 336 adult patients were analyzed. False-positive (mostly bacterial) and false-negative (mostly viral) cases were deciphered with the help of clinical data. The performance of the FilmArray ME panel in our study was better for bacterial detection (specificity >99%, sensitivity 100%) than viral detection (specificity >99%, sensitivity 75% for herpes simplex virus 1 [HSV-1] and 89% for enterovirus), our study being one of the largest, to date, concerning enteroviruses. The use of a threshold of 10 leukocytes/mm³ considerably increased the positive agreement between the results of the FilmArray ME panel and the clinical features, especially for bacterial pathogens, for which agreement increased from 58% to 87%, avoiding two-thirds of inappropriate testing. Based on this analysis, we propose an algorithm for the use of both syndromic and specific assays for the optimal management of suspected meningitis/encephalitis in adult and pediatric patients.

IMPORTANCE Based on our comparative analysis of performances of the diagnostic assays, we propose an algorithm for the use of both syndromic and specific assays, for an optimal care of the meningitis/encephalitis threat in adult and pediatric patients.

Comparison of a Point-of-Care FilmArray Test to Standard-of-Care Microbiology Test in Diagnosis of Healthcare Associated Infections in a Tertiary Care Pediatric Intensive Care Unit

Background: Rapid and accurate identification of healthcare associated pathogens is crucial for early diagnosis and treatment of infections. This study aimed to assess the performance of a point-of-care multiplex polymerase chain reaction (PCR) in diagnosis of pathogens and their antibiotic resistance genes in bloodstream infections, pneumonia and meningitis/encephalitis in a pediatric intensive care unit (PICU). Methods: A retrospective cross-sectional study was conducted on pediatric patients diagnosed with healthcare associated infections at Alexandria University PICU, Egypt. A total of 111 samples from 98 patients were subjected simultaneously to standard-of-care microbiology testing (SOCMT) and molecular testing by BioFire multiplex PCR. Results: In comparison to SOCMT, the BioFire FilmArray^® had a better diagnostic yield with broncho-alveolar lavage (BAL) (45 vs. 21) and cerebrospinal fluid (CSF) samples (five vs. none) (p ≤ 0.0001). Klebsiella pneumoniae was the most common pathogen in BAL (n = 19 by BioFire, n = 9 by SOCMT) and blood (n = 7, by SOCMT and BioFire) samples, while Streptococcus pneumoniae was the most common in CSF samples. BioFire showed 95.8% overall percent agreement, 100% positive percent agreement and 95.6% negative percent agreement with SOCMT. All phenotypically confirmed resistant isolates had resistance genes by the BioFire FilmArray^® (100%). The turnaround time (TAT) of positive results by the FilmArray panels was 1–1.5 h in comparison to 48–72 h by SOCMT (p ≤ 0.001). Conclusions: The results of the current study confirm the utility of the BioFire FilmArray^® in making early decisions regarding patients’ diagnosis and management of infection in the PICU, in terms of rapid TAT and appropriate antimicrobial use.

Biofire FilmArray Meningitis/Encephalitis panel for the aetiological diagnosis of central nervous system infections: A systematic review and diagnostic test accuracy meta-analysis

BACKGROUND

The FilmArray Meningitis/Encephalitis(FA/ME) panel brings benefits in clinical practice, but its diagnostic test accuracy (DTA) remains unclear. We aimed to determine the DTA of FA/ME for the aetiological diagnostic in patients with suspected central nervous system(CNS) infection.

METHODS

We performed a systematic review with DTA meta-analysis (PROSPERO: CRD42020139285). We searched Embase, Medline (Ovid), and Web of Science from inception until September 1st, 2021. We assessed the study-level risk of bias with the QUADAS-2 tool and applied the GRADE approach to assess the certainty of the synthesised evidence. We included studies that simultaneously measured the reference test (CSF/blood culture for bacteria, and specific polymerase chain reaction for viruses) and the FA/ME in patients with suspected CNS infection. We performed random-effects bivariate meta-analysis models of combined sensitivity and specificity using CSF/blood cultures(reference test 1) and a final diagnosis adjudication based on clinical/laboratory criteria (reference test 2).

FINDINGS

We included 19 studies (11,351 participants). For all bacteria with reference test 1 (16 studies/6183 patients) sensitivity was estimated at 89·5% (95%CI 81·1-94·4), and specificity at 97·4% (95%CI 94-98·9). With reference test 2 (15 studies/5,524 patients), sensitivity was estimated at 92·1%(95%CI 86·8-95·3) and specificity at 99.2(95%CI 98·3-99·6) For herpes simplex virus-2(HSV-2), enteroviruses, and Varicella-Zoster virus (VZV), we obtained sensitivities between 75·5 and 93·8%, and specificities above 99% (reference test 1). Certainty of the evidence was low.

INTERPRETATION

FA/ME may have acceptable-to-high sensitivities and high specificities for identifying bacteria, especially for S.pneumoniae, and viruses, especially for HSV-2, and enteroviruses. Sensitivities for L.monocytogenes, H.influenzae, E.coli, and HSV-1 were suboptimal.

FUNDING

None.

Optimal encephalitis/meningitis roadmap via precise diagnosis and treatment (IMPROVE): a study protocol for a randomized controlled trial

BACKGROUND

Encephalitis/meningitis brings a heavy disease burden, and the origin of disease remains unknown in 30-40% of patients. It is greatly significant that combinations of nucleic acid amplification and autoimmune antibody testing improves the diagnosis and treatment of encephalitis/meningitis. Moreover, though several diagnostic methods are in clinical use, a recognized and unified diagnosis and treatment process for encephalitis management remains unclear.

METHODS

IMPROVE is a multicenter, open label, randomized controlled clinical trial that aims to evaluate the diagnostic performance, applications, and impact on patient outcomes of a new diagnostic algorithm that combines metagenomic next-generation sequencing (mNGS), multiplex polymerase chain reaction (PCR) and autoimmune antibody testing. The enrolled patients will be grouped into two parallel groups, multiplex PCR test plus autoimmune antibody group (Group I) or the mNGS plus autoimmune antibody group (Group II) with a patient ratio of 1:1. Both groups will be followed up for 12 months. The primary outcomes include the initial time of targeted treatment and the modified Rankin scale score on the 30th day of the trial. The secondary outcomes are the cerebrospinal fluid index remission rate on the 14th day, mortality rate on the 30th day, and an evaluation of diagnostic efficacy. The two groups are predicted to comprise of 484 people in total.

DISCUSSION

To optimize the roadmap of encephalitis/meningitis, precise diagnosis, and treatment are of great significance. The effect of rapid diagnosis undoubtedly depends on the progression of new diagnostic tests, such as the new multiplex PCR, mNGS, and examination of broad-spectrum autoimmune encephalitis antibodies. This randomized-controlled study could allow us to obtain an accurate atlas of the precise diagnostic ability of these tests and their effect on the treatment and prognosis of patients. Trial registration ClinicalTrial.gov, NCT04946682. Registered 29 June 2021, 'Retrospectively registered', https://clinicaltrials.gov/ct2/show/NCT04946682?term=NCT04946682&draw=2&rank=1.

Molecular diagnosis of the central nervous system (CNS) infections

Central nervous system (CNS) infections such as meningitis and encephalitis are medical emergencies that require rapid diagnosis of the causative pathogen to guide early and adequate treatment since a delay in implementing an adequate antimicrobial therapy can lead to death. The current microbiological diagnostic methods based on culture or antigen detection have important limitations in their capacity to accurately identify the different potential pathogens causing CNS and, in the time, to obtaining results. Rapid syndromic molecular arrays have been developed. The main advantage of using a meningoencephalitis panel based in a multiplex test is that includes bacteria, viruses and fungi, covering the most prevalent microorganisms causing meningitis and encephalitis and the turn-around time is circa 1h. The use of these multiplex-PCR based tools is reviewed and the advantages and disadvantages of this technique are discussed.

Assessment of a Multiplex LAMP Assay (Eazyplex® CSF Direct M) for Rapid Molecular Diagnosis of Bacterial Meningitis: Accuracy and Pitfalls

Background: Automated molecular panels are attractive tools for improving early meningitis diagnosis. This study assessed the Eazyplex^® CSF direct M panel (EP), a multiplex real-time Loop-Mediated Isothermal Amplification assay. Methods: From December 2016 to December 2019, cerebrospinal fluid (CSF) samples were routinely tested with the EP V1.0. CSF parameters and microbiological and clinical data were retrospectively collected. Results: Out of 230 CSF samples, the EP yielded positive, negative, and invalid results for 32 (13.9%) (16 N. meningitidis, nine S. pneumoniae, two S. agalactiae, two E. coli, two H. influenzae, one L. monocytogenes), 182 (79.1%), and 16 (7%) samples, respectively. Among the positive samples, 14 (44%) remained negative in culture (antibiotic therapy before lumbar puncture (n = 11), meningococcal meningitis (n = 3)). High CSF protein concentrations and cellularity were associated with LAMP inhibition, counteracted by centrifugation. The automated software yielded 13 false positive and five false negative results. Amplification curve analysis was necessary and enabled the attainment of positive (PPA) and negative percentage agreement and positive and negative predictive values of 91.4%, 100%, 100%, and 98.3%. Three false negative results remained (two E. coli and one N. meningitidis). E. coli presented the poorest PPA (50%). Conclusion: This work confirms the strong performance of the EP, of particular interest in cases of antibiotic therapy before lumbar puncture.

Clinical Significance of Positive Results of the BioFire Cerebrospinal Fluid FilmArray Meningitis/Encephalitis Panel at a Tertiary Medical Center in the United States

CONTEXT.—

The FilmArray Meningitis/Encephalitis (ME) panel is the first US Food and Drug Administration-cleared multiplex polymerase chain reaction panel for the detection of central nervous system infections. While the assay's performance characteristics have been described, the real-world significance of positive results has not been fully characterized.

OBJECTIVE.—

To evaluate the clinical significance of positive ME panel results in a tertiary care medical center in New York, New York.

DESIGN.—

Four physicians independently performed retrospective clinical assessments of all positive ME panel results at Columbia University Irving Medical Center, including the Children's Hospital of New York, during an 18-month period. Each reviewer determined the likelihood of central nervous system infection for all cases and whether cases fit Brighton diagnostic criteria for meningitis, encephalitis, or meningoencephalitis.

RESULTS.—

Among 119 cases, there was 75% positive agreement (95% CI, 54%-89%) between ME panel results and clinical consensus, which varied among panel targets.

CONCLUSIONS.—

The ME panel showed good agreement with expert clinical consensus for patients presenting with acute meningitis/encephalitis. Factors contributing to clinically insignificant ME positive results included low pretest probability, traumatic lumbar puncture, specimen contamination, and detection of incidental viral targets such as human herpesvirus 6. Notably, the ME panel detected more than twice the number of cases of bacterial meningitis detected by culture alone, particularly among patients receiving empiric antimicrobial therapy before lumbar puncture. Appropriate test use and contextual interpretation of results are critical to leveraging the advantages of the platform while avoiding potential pitfalls.

The yield of CSF molecular testing in febrile neonates

We retrospectively examined the yield of a cerebrospinal fluid (CSF) multiplex real-time PCR assay of febrile young infants undergoing a full sepsis work-up. Eighty infants were included in the study: Forty-nine (61%) neonates and 31 (39%) 29-90 day-old patients were included in the study. A viral pathogen was detected in 59% (47/80) of the samples, human enterovirus in 53% (42/80) and Human parechovirus in 6% (5/80). The CSF of nearly half of the subjects with CNS infection was without pleocytosis; all CSF cultures were negative. Multiplex PCR CSF testing enhances the diagnosis of pathogen-specific viral CNS infection among febrile young infants.

Clinical utility of the FilmArray meningitis/encephalitis panel in children at a tertiary center in South Korea

BACKGROUND

We retrospectively evaluated the pathogens in the cerebrospinal fluid (CSF) of pediatric meningitis/encephalitis (M/E) by FilmArray meningitis/encephalitis panel (FA-MEP), and the characteristics of children showing positive and negative FA-MEP results.

METHOD

FA-MEP along with conventional tests (bacterial/viral cultures, and polymerase chain reaction tests) was performed in children who presented symptoms of M/E. Clinical and laboratory data were reviewed to evaluate the characteristics of children with pathogens detected by FA-MEP.

RESULTS

The CSF specimens from 110 pediatric M/E patients were enrolled. Mean age of the patients was 5.9 ± 5.2 years. Overall positive rate of FA-MEP was 46.4% (51/110). The pathogens detected in the patients were enterovirus (23/51, 45.1%), parechovirus (10/51, 19.6%), S. pneumoniae (7/51, 13.7%), human herpesvirus type 6 (6/51, 11.8%), S. agalactiae (3/51, 5.9%), herpes simplex virus type 2 (1/51, 2.0%), and E. coli (1/51, 2.0%). Aseptic meningitis (OR, 3.24, 95% CI, 1.18-12.73) and a duration of <2 days from onset of symptoms to CSF test (OR, 3.56, 95% CI, 0.1-0.91) significantly contributed to detection of pathogens by the FA-MEP. Among the 14 children who were administered empiric antibiotics before the CSF test, the detection rate was significantly higher in the FA-MEP than in the conventional test (28.6 vs. 0.0%, p = 0.031).

CONCLUSIONS

FA-MEP had a higher detection rate in children with M/E compared with conventional tests, particularly aseptic meningitis, and in case of shorter duration of time-to-test. This test was more effective than the conventional test in pediatric M/E patients that had been administered empiric antibiotics.

Postnatally acquired CMV meningitis diagnosed via BioFire FilmArray: A case report

Postnatally acquired cytomegalovirus (CMV) is commonly acquired via breast milk, with premature infants more frequently developing symptoms of CMV infection in comparison to term infants. Meningitis is a rare clinical manifestation of CMV infection. The diagnosis of meningitis is difficult to make in infants, particularly those who are preterm. Consequentially, broad-spectrum empiric antimicrobial coverage is often administered for several days while waiting for current gold standard CSF testing to result. The BioFire FilmArray (BFA) simultaneously tests for 14 different pathogens, including CMV, allowing for quicker diagnosis and shorter time to definitive treatment. Here, we report a very low birth weight infant with postnatally acquired CMV meningitis, the first to our knowledge to be diagnosed using the BioFire FilmArray.

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.

Burden of Pediatric Central Nervous System Infection and Cost-Benefit Simulation of Multiplex Polymerase Chain Reaction in Japan

To investigate the clinical use of multiplex polymerase chain reaction (mPCR) in Japan, epidemiological and clinical data for central nervous infections are needed. Here, we report on the epidemiology and economic burden of central nervous system infections and a simulation of the cost-benefit analysis of the Filmarray® Meningitis/Encephalitis (FAME) test for possible clinical use in Japan. We performed FAME tests on samples from 27 patients with pleocytosis aged between 0 and 20 years seen in six community hospitals in Nara and Osaka prefectures. All clinical management procedures were performed without knowledge of the mPCR test results. We analyzed the clinical data and calculated the required reduction in average length of stay for the FAME test to be cost-beneficial. Among the 27 cases, the FAME test revealed causal pathogens in 13 cases (48.1%). The average medical and social costs per case were ¥299,118 ($2,719.2) and ¥171,768 ($1,561.5), respectively. The minimal needed reduction in average length of stay for the FAME test to be cost-beneficial was 0.32- 0.86 days per meningitis case. The result can be informative for evaluating the cost-effectiveness of the clinical use of the FAME test in Japan.

Tracheal colonization factor A (TcfA) is a biomarker for rapid and specific detection of Bordetella pertussis

Pertussis is a highly contagious disease for which prompt, point-of-care diagnosis remains an unmet clinical need. Results from conventional test modalities (nucleic acid detection, serology, and culture) take hours to days. To overcome this challenge, we identified a new biomarker (tracheal colonization factor A, TcfA) for detection of Bordetella pertussis infection by lateral flow immunoassay (LFIA). We developed a library of 28 epitope-mapped monoclonal antibodies against TcfA and incorporated three antibodies into a LFIA. The LFIA did not cross-react with common bacterial or fungal organisms, but did react with nine distinct B. pertussis strains. The minimal linear epitope sequences targeted by the LFIA were conserved in 98% of 954 B. pertussis isolates collected across 12 countries from 1949–2017. The LFIA’s limit of detection was 3.0 × 10⁵ CFU/mL with B. pertussis cells in buffer, 6.2 × 10⁵ CFU/mL with nasopharyngeal washes from a non-human primate model, and 2.3 ng/mL with recombinant TcfA. The LFIA reacted with patient nasopharyngeal swab specimens containing as few as 1.8 × 10⁶B. pertussis genomes/mL and showed no false-positives. Rapid (< 20 min) LFIA detection of TcfA as a biomarker for B. pertussis infection is feasible and may facilitate early detection of pertussis.

Unusual presentation of meningococcal meningitis in the elderly and utility of CSF PCR testing

We present an unusual case of a previously healthy 74-year-old man who presented with diffuse weakness, severe myalgias, petechial palmar rash and hypotension, but without fever, altered mental status, nuchal rigidity or headache, who was ultimately found through PCR testing to have meningococcal meningitis.

Human Herpesvirus 6 Detection during the Evaluation of Sepsis in Infants Using the FilmArray Meningitis/Encephalitis Panel

We used the FilmArray meningitis/encephalitis panel for evaluation of sepsis in febrile neonates. We detected human herpesvirus 6, a virus we did not routinely test for previously, in the cerebrospinal fluid of 7 neonates. In all 7 cases, detection of the virus did not warrant antiviral treatment.

The epidemiology of FIRS in term and late preterm births

The definition of FIRS requires systemic inflammation and elevated levels of IL-6 in fetal plasma. That definition does not specify how systemic inflammation is to be recognized, and perinatal measurement of IL-6 is not a standard procedure. FIRS has not been examined in a population-based study that included post-neonatal outcome so its incidence and natural history are not known. The overlap, and similarities and differences, of FIRS as compared with other causes of neonatal encephalopathy, and how these relate to findings in the placenta, have not been jointly examined in a generalizable sample. FIRS has chiefly been discussed in the obstetric literature because of the need for decisions about management of delivery and antibiotic use. If the term "FIRS" is to be employed in other contexts, consensus should be sought as to which clinical, placental, and laboratory findings are most appropriate for identification of perinatal inflammatory processes, infectious or sterile.

Impact of cerebrospinal fluid syndromic testing in the management of children with suspected central nervous system infection

The aim of the study was to evaluate the impact of the use of BioFire® FilmArray® meningitis/encephalitis(FA-ME) panel which enables rapid automated CSF testing for 14 common viral, bacterial, and yeast pathogens that cause CNS infections, in the management of children with suspected CNS infection. A prospective cohort study was performed on children admitted to a tertiary pediatric hospital, over a period of 1 year, with possible CNS infection and CSF pleocytosis (> 15 cells/mm³). Children were randomized 1:1, either to use FA-ME or separate molecular CSF microbiological tests according to usual pediatric practice in the hospital. Length of hospital stay, duration of antimicrobials, and total cost of hospitalization were compared between groups. A total of 142 children were included in the study (71 cases). A pathogen was detected in 37/71(52.1%) children with the use of FA-ME and in 16/71(22.5%) in the control group (P value < 0.001). In aseptic meningitis cases a virus was detected in 27/61(44.2%) and in 11/66(16.7%) controls (P value < 0.001). Median (IQR) length of stay in cases and controls with aseptic meningitis was 5(4-8) and 8(6-10) days, respectively (P value < 0. 001). The median (IQR) duration of antimicrobials in cases and controls was 4(2-5.7) and 7(5-10) days, respectively (P value < 0.001). The hospitalization cost was calculated in cases and controls 1042€ (932-1372) and 1522€ (1302-1742), respectively (P value < 0.001). The use of FA-ME was able to reduce significantly the use of antimicrobials, the hospitalization days, and the total cost comparing to the control group in children with suspected CNS infection.

Molecular diagnosis of the central nervous system (CNS) infections

Central nervous system (CNS) infections such as meningitis and encephalitis are medical emergencies that require rapid diagnosis of the causative pathogen to guide early and adequate treatment since a delay in implementing an adequate antimicrobial therapy can lead to death. The current microbiological diagnostic methods based on culture or antigen detection have important limitations in their capacity to accurately identify the different potential pathogens causing CNS and, in the time, to obtaining results. Rapid syndromic molecular arrays have been developed. The main advantage of using a meningoencephalitis panel based in a multiplex test is that includes bacteria, viruses and fungi, covering the most prevalent microorganisms causing meningitis and encephalitis and the turn-around time is circa 1h. The use of these multiplex-PCR based tools is reviewed and the advantages and disadvantages of this technique are discussed.

Pathogen or Bystander: Clinical Significance of Detecting Human Herpesvirus 6 in Pediatric Cerebrospinal Fluid

Human herpesvirus 6 (HHV-6) is an important cause of meningitis and meningoencephalitis. As testing for HHV-6 in cerebrospinal fluid (CSF) is more readily available using the FilmArray Meningitis/Encephalitis panel (FA-ME; BioFire Diagnostics, Salt Lake City, UT), we aimed to determine the clinical significance of detecting HHV-6 in order to identify true infections and to ensure appropriate antiviral initiation. Chart review on 25 patients positive for HHV-6 by FA-ME was performed to determine clinical presentation, comorbidity, treatment, and outcome. The presence of chromosomally integrated HHV-6 (ciHHV-6) DNA was also investigated. Of 1,005 children tested by FA-ME, HHV-6 was detected in 25 (2.5%). Five patients were diagnosed with either HHV-6 meningitis or meningoencephalitis based on HHV-6 detection in CSF, clinical presentation, and radiographic findings. Detection of HHV-6 by FA-ME led to discontinuation of acyclovir within 12.0 h in all 12 patients empirically treated with acyclovir. Six of the 12 patients were started on ganciclovir therapy within 6.8 h; 4 of these were treated specifically for HHV-6 infection, whereas therapy was discontinued in the remaining 2 patients. CSF parameters were not generally predictive of HHV-6 positivity. The presence of ciHHV-6 was confirmed in 3 of 18 patients who could be tested. Five of the 25 patients included in the study were diagnosed with HHV-6 meningitis/meningoencephalitis. FA-ME results led to discontinuation of empirical antiviral treatment in 12 patients and appropriate initiation of ganciclovir in 4 patients. In our institution, detection of HHV-6 using FA-ME led to faster establishment of disease etiology and optimization of antimicrobial therapy.

Rapid diagnostic tests for infectious diseases in the emergency department

Background

Rapid diagnostic tests (RDTs) for infectious diseases, with a turnaround time of less than 2 hours, are promising tools that could improve patient care, antimicrobial stewardship and infection prevention in the emergency department (ED) setting. Numerous RDTs have been developed, although not necessarily for the ED environment. Their successful implementation in the ED relies on their performance and impact on patient management.

Objectives

The aim of this narrative review was to provide an overview of currently available RDTs for infectious diseases in the ED.

Sources

PubMed was searched through August 2019 for available studies on RDTs for infectious diseases. Inclusion criteria included: commercial tests approved by the US Food and Drug Administration (FDA) or Conformité Européenne (CE) in vitro diagnostic devices with data on clinical samples, ability to run on fully automated systems and result delivery within 2 hours.

Content

A nonexhaustive list of representative commercially available FDA- or CE-approved assays was categorized by clinical syndrome: pharyngitis and upper respiratory tract infection, lower respiratory tract infection, gastrointestinal infection, meningitis and encephalitis, fever in returning travellers and sexually transmitted infection, including HIV. The performance of tests was described on the basis of clinical validation studies. Further, their impact on clinical outcomes and anti-infective use was discussed with a focus on ED-based studies.

Implications

Clinicians should be familiar with the distinctive features of each RDT and individual performance characteristics for each target. Their integration into ED work flow should be preplanned considering local constraints of given settings. Additional clinical studies are needed to further evaluate their clinical effectiveness and cost-effectiveness.

Implementation of the FilmArray ME panel in laboratory routine using a simple sample selection strategy for diagnosis of meningitis and encephalitis

Background

Infectious meningitis is a serious disease and patient outcome relies on fast and reliable diagnostics. A syndromic panel testing approach like the FilmArray ME can accelerate diagnosis and therefore decrease the time to pathogen specific therapy. Yet, its clinical utility is controversial, mainly because of a remaining uncertainty in correct interpretation of results, limited data on its performance on clinical specimens and its relatively high costs. The aim of this study was to analyze clinical performance of the assay in a real life setting at a tertiary university hospital using a pragmatic and simple sample selection strategy to reduce the overall cost burden.

Methods

Over a period of 18 months we received 4623 CSF samples (2338 hospitalizations, 1601 individuals). FilmArray ME analysis was restricted to CSF-samples with a high pretest probability of infectious meningitis, e.g. positive Gram-stain, samples in which leukocytes and/or bacteria were evident or urgent suspicion of infection was communicated by clinicians. N = 171 samples matched to our risk criteria and were subjected to FilmArray ME analysis. Those samples were also analyzed by reference methods: culture only (n = 45), PCR only (n = 20) or both methods (n = 106).

Results

56/171 (32.75%) were FilmArray ME positive. Bacterial pathogens were detected in 30/56 (53.57%), viral pathogens were detected in 27/56 (48.21%) and yeast DNA was detected in 1/56 (1.79%) of positive samples. Double detection occurred in 2/56 samples. In 52/56 (92.86%) FilmArray ME positive samples, results could be confirmed by the reference assays (sensitivity = 96.30%, specificity =96.58%).

Conclusion

The FilmArray ME assay is a fast and reliable diagnostic tool for the management of infectious meningitis and can easily be implemented in routine diagnostic workflows. However, correlation of test results and underlying clinical symptoms requires experienced users and the awareness of potentially false negative or false positive results. Moreover, considering the need for antimicrobial susceptibility testing, the use of molecular tests as a stand-alone diagnostic cannot be recommended.

Comparison of antibiotic and acyclovir usage before and after the implementation of an on-site FilmArray meningitis/encephalitis panel in an academic tertiary pediatric hospital: a retrospective observational study

BACKGROUND

Prompt initiation of empiric therapy is common practice in case of suspected meningitis or encephalitis. However, in children the most common pathogens are viruses that usually do not require and are not covered by the applied anti-infective treatment. Novel multiplex PCR (mPCR) panels provide rapid on-site diagnostic testing for a variety of pathogens. This study compared empiric antibiotic and acyclovir usage before and after the introduction of an on-site FilmArray Meningitis/Encephalitis Panel (FA ME Panel).

METHODS

We retrospectively compared data for empiric antibiotic and acyclovir usage between pediatric patients with suspected central nervous system (CNS) infection receiving mPCR testing and a matched historical control group. Patients were matched by age and suspected CNS infection. We included all patients for whom empiric antibiotics and/or acyclovir were prescribed.

RESULTS

Each study group consisted of 46 patients with 29 (63.0%) infants and 17 (37.0%) older children. A viral pathogen was diagnosed in 5/46 (10.9%) patients in the control group (all enteroviruses) and in 14/46 (30.4%) patients in the mPCR group (enterovirus n = 9; human herpesvirus 6 (HHV-6) n = 5), (p = 0.038)). Length of Therapy (LoT) and Days of Therapy (DoT) for antibiotics were significantly lower for infants (4.0 vs. 3.0, p = 0.038 and 8.0 vs. 6.0, p = 0.015, respectively). Acyclovir therapy was significantly shorter for both, infants and older children (3.0 vs. 1.0 day, p < 0.001 for both age groups).

CONCLUSION

The findings of our study suggest that the introduction of a FA ME Panel into clinical routine procedures is associated with a significantly reduced LoT and DoT of empiric anti-infective treatment in children with suspected meningoencephalitis. The largest effect was observed in infants.

Childhood Infectious Encephalitis: An Overview of Clinical Features, Investigations, Treatment, and Recent Patents

BACKGROUND

Infectious encephalitis is a serious and challenging condition to manage. This overview summarizes the current literature regarding the etiology, clinical manifestations, diagnosis, management, and recent patents of acute childhood infectious encephalitis.

METHODS

We used PubMed Clinical Queries as a search engine and used keywords of "encephalitis" AND "childhood" Patents were searched using the key term "encephalitis" in google.patents.- com and patentsonline.com.

RESULTS

Viral encephalitis is the most common cause of acute infectious encephalitis in children. In young children, the clinical manifestations can be non-specific. Provision of empiric antimicrobial therapy until a specific infectious organism has been identified, which in most cases includes acyclovir, is the cornerstone of therapy. Advanced investigation tools, including nucleic acid-based test panel and metagenomic next-generation sequencing, improve the diagnostic yield of identifying an infectious organism. Supportive therapy includes adequate airway and oxygenation, fluid and electrolyte balance, cerebral perfusion pressure support, and seizure control. Recent patents are related to the diagnosis, treatment, and prevention of acute infectious encephalitis.

CONCLUSION

Viral encephalitis is the most common cause of acute infectious encephalitis in children and is associated with significant morbidity. Recent advances in understanding the genetic basis and immunological correlation of infectious encephalitis may improve treatment. Third-tier diagnostic tests may be incorporated into clinical practice. Treatment is targeted at the infectious process but remains mostly supportive. However, specific antimicrobial agents and vaccines development is ongoing.

Diagnostic challenges of central nervous system infection: extensive multiplex panels versus stepwise guided approach

BACKGROUND

Cerebrospinal fluid (CSF) testing is a key component for the diagnosis of central nervous system (CNS) infections. Current meningitis and encephalitis management guidelines agree on the need for CSF molecular testing in combination with other direct and indirect biological testing, both in CSF and blood. Multiplex molecular tests have been developed to reduce turnaround times and facilitate the diagnostic approach.

OBJECTIVES

We aim to discuss the role of multiplex molecular panels in the management of CNS infections.

SOURCES

The MEDLINE database and the grey literature have been searched for relevant articles.

CONTENT

New molecular multiplex panels are being developed to simultaneously detect a large array of neuropathogens in CSF. Although one of these assays has been US Food and Drug Administration-approved, extensive analytical and clinical validation is still missing, and suboptimal performance related issues have been raised. Its use has been associated with decreased costs, reduced length of hospital stay and reduced antiviral therapy administration in retrospective, industry-sponsored studies. The pros and cons of this multiplex syndromic approach are discussed in this narrative review.

IMPLICATIONS

Molecular multiplex CNS infection diagnosis panels have been developed and present several attractive features, including ease of use and low turnaround time. However, suboptimal analytical performances render these tests difficult to use without additional confirmatory tests. Such panels are not comprehensive nor adapted to all situations, depending on the epidemiological or clinical context. Overall, available data in the literature currently do not support the use of a multiplex PCR panel in clinical routine as a 'stand-alone' molecular assay. Except in restricted laboratory capacity settings where such easy-to-use multiplex panels offer the diagnostic means that would otherwise not be available, the stepwise testing approach remains a more rational option. Serological testing both in blood and CSF should not be neglected, but it represents essential complementary tools regarding some neuropathogens.

Development and validation of a multiplex-PCR based assay for the detection of 18 pathogens in the cerebrospinal fluid of hospitalized children with viral encephalitis

BACKGROUND

The Applied Biosystems 3500 Genetic Analyzer (ABI3500) allows for automated capillary electrophoresis on multiple targets. So far, the application of this method for detecting cerebrospinal fluid pathogens has hardly been reported.

METHODS

To assess the performance of multiplex-PCR assay for 18 pathogens detection, 127 CSF samples from hospitalized children with suspected viral encephalitis were prospectively collected from April to November 2018. The Sanger sequencing was applied to verify this assay.

RESULTS

All of the 18 target pathogens can be identified by multiplex-PCR assay at 10⁴ copies (or CFU/mL) of each virus, bacterium and fungus. In contrast, 10 control microorganisms failed to be amplified. Approximately 68.5 % of the cases tested had positive results, the enterovirus accounted for the majority of the positive cases (63.8 %). Agreement between multiplex-PCR and sequencing was 91.49 %.

CONCLUSIONS

Our findings suggest that the ABI3500-based multiplex-PCR detection kit could be a valuable diagnostic tool for pathogen detection in CSF of children with suspected viral encephalitis.

Impact of a multiplex PCR assay (FilmArray®) on the management of patients with suspected central nervous system infections

Microbiological diagnosis of central nervous system (CNS) infections is challenging due to limited access to CNS samples, overlap between meningitis and encephalitis, and the multiplicity of pathogens potentially involved. We aimed to estimate the impact of a commercial multiplex PCR assay (FilmArray® meningitis/encephalitis) on the management of patients with suspicion of meningitis or encephalitis, in terms of time to diagnosis, antimicrobial agents use, duration of hospitalization, and costs. This prospective observational study was conducted at Saint Joseph Hospital (Paris, France) from December 2016 to December 2017. All CSF samples sent to the microbiology laboratory for suspicion of meningitis and/or encephalitis, with CSF cells count > 5 cells/μL, were tested by meningitis/encephalitis multiplex PCR assay. One hundred thirty patients were included. The multiplex PCR assay was positive in 33 patients (25%). Main pathogens found were Enterovirus (n = 12), Varicella-Zoster virus (n = 7), Herpes simplex virus-2 (n = 6), and Listeria monocytogenes (n = 3) as main pathogens. The multiplex PCR assay reduced time to microbiological diagnosis by 3.3 ± 1.6 days and allowed an earlier discontinuation of empirical anti-infective drugs in 42 patients (32%) and an earlier hospital discharge in 23 patients (18%), with an estimated saving of 82 hospital days overall, and a management cost reduction of 26,242 € (201 €/patient). The systematic use of the FilmArray® meningitis/encephalitis multiplex PCR assay may allow earlier diagnosis, earlier discontinuation of empirical treatment, reduced duration of stay, and costs reduction.

A review of a 13-month period of FilmArray Meningitis/Encephalitis panel implementation as a first-line diagnosis tool at a university hospital

Early diagnosis and treatment of meningitis and encephalitis is essential for reducing both their morbidity and mortality. The FilmArray^® Meningitis/Encephalitis (FA-M/E) panel is a recently available molecular tool allowing the simultaneous detection of 14 pathogens in about one hour. We evaluated its routine use over a 13-month period at Nîmes University Hospital, France. Cerebrospinal fluid (CSF) specimens were prospectively analyzed, independently of cell count; results were retrospectively analyzed and positive results compared to clinical and microbiological data. Among the 708 patients included (734 CSF samples), 89 (12.6%) had a positive FA-M/E panel, 71 (80%) for a viral pathogen and 18 (20%) for a bacterial pathogen. Enterovirus and HHV-6 were the main detected pathogens. Mean time-to-results was 1h46mn. Four non-clinically relevant results were detected (3 HHV-6 and 1 Haemophilus influenzae) on the basis of inconsistent clinical and/or biological data, and/or after visualization of melting curves. No CSF pleocytosis was observed in 11% of the patients with a positive FA-M/E panel. For the 18 patients with a positive FA-M/E panel for a bacterial pathogen, five (28%) had CSF samples showing a positive Gram stain allowing an early diagnosis of bacterial infection and 67% had CSF displaying a positive culture. Altogether the panel detected 5 cases of bacterial M/E (29%) not diagnosed by culture. Despite undeniable advantages, mainly ease of use, quick result availability, and an extremely low rate of invalid results, measures should be implemented to limit false-positive results due to contamination and a careful interpretation based on the overall data for each patient is required.

Approche syndromique multiplexe en réanimation

Le développement récent des nouveaux tests de diagnostic rapide par PCR multiplexe à visée syndromique, capables de détecter plusieurs dizaines de pathogènes en quelques heures, a entraîné un changement de paradigme en microbiologie et en pratique clinique. Plusieurs d’entre eux, comme les panels pour détecter les germes en cause dans les bactériémies, les infections respiratoires hautes ou basses et les méningoencéphalites, sont déjà disponibles et peuvent apporter une aide dans le diagnostic des infections chez les patients de réanimation. Bien que ces nouvelles techniques présentent des avantages évidents pour le dénombrement de micro-organismes et parfois pour la détection simultanée de gènes de résistance, pour les délais d’exécution et de rendus de résultats, elles présentent cependant certains défis, comme l’évaluation de leurs performances réelles, leur coût très élevé, le choix des stratégies d’utilisation et l’interprétation clinicobiologique des résultats. Dans cet article, nous avons passé en revue les différents tests qui peuvent ou pourront aider les réanimateurs dans leur pratique quotidienne, relevé leurs limites et leur impact bénéfique potentiel sur le soin des patients.

[Meningitis/Encephalitis diagnosis in ICU using Multiplex PCR system: Is it time of change?]

OBJECTIVE

To evaluate the clinical impact of Meningitis/Encephalitis FilmArray® panel for the diagnosis of cerebral nervous system infection and to compare the results (including time for diagnosis) with those obtained by conventional microbiological techniques.

METHODS

A prospective observational study in an Intensive Care Unit of adults from a tertiary hospital was carried out. Cerebrospinal fluid from all patients was taken by lumbar puncture and assessed by the meningitis/encephalitis FilmArray® panel ME, cytochemical study, Gram, and conventional microbiological cultures.

RESULTS

A total of 21 patients admitted with suspicion of Meningitis/Encephalitis. Median age of patients was 58.4 years (RIQ 38.1-67.3), median APACHE II 18 (RIQ 12-24). Median stay in ICU and median hospital stay was 4 (RIQ 2-6) and 17 days (RIQ 14-28), respectively. The overall mortality was 14.3%. A final clinical diagnosis of meningitis or encephalitis was established in 16 patients, obtaining the etiological diagnosis in 12 of them (75%). The most frequent etiology was Streptococcus pneumoniae (8 cases). FilmArray® allowed etiological diagnosis in 3 cases in which the culture had been negative, and the results led to changes in the empirical antimicrobial therapy in 7 of 16 cases (43.8%). FilmArray® yielded a global sensitivity and specificity of 100% and 90%, respectively. The median time to obtain results from the latter and conventional culture (including antibiogram) was 2.9 hours (RIQ 2.1-3.8) and 45.1 hours (RIQ 38.9-58.7), respectively.

CONCLUSIONS

The Meningitis/Encephalitis FilmArray® panel was able to establish the etiologic diagnosis faster than conventional methods. Also, it achieved a better sensitivity and led to prompt targeted antimicrobial therapy.

Interplay between Rapid Diagnostic Tests and Antimicrobial Stewardship Programs among Patients with Bloodstream and Other Severe Infections

BACKGROUND

Antimicrobial stewardship programs (ASPs) aim to provide optimal antimicrobial therapy to patients quickly to improve the likelihood of overcoming infection while reducing the risk of adverse effects. Rapid diagnostic tests (RDTs) for infectious diseases have become an integral tool for ASPs to achieve these aims.

CONTENT

This review explored the demonstrated clinical value of longer-standing technologies and implications of newer RDTs from an antimicrobial stewardship perspective. Based on available literature, the focus was on the use of RDTs in bloodstream infections (BSIs), particularly those that perform organism identification and genotypic resistance detection, phenotypic susceptibility testing, and direct specimen testing. Clinical implications of rapid testing among respiratory, central nervous system, and gastrointestinal infections are also reviewed.

SUMMARY

Coupling RDTs with ASPs facilitates the appropriate and timely use of test results, translating into improved patient outcomes through optimization of antimicrobial use. These benefits are best demonstrated in the use of RDT in BSIs. Rapid phenotypic susceptibility testing offers the potential for early pharmacokinetic/pharmacodynamic optimization, and direct specimen testing on blood may allow ASPs to initiate appropriate therapy and/or tailor empiric therapy even sooner than other RDTs. RDTs for respiratory, central nervous system, and gastrointestinal illnesses have also shown significant promise, although more outcome studies are needed to evaluate their full impact.

Cost of managing meningitis and encephalitis among infants and children in the United States

A retrospective cohort study design was used to assess the use and costs of diagnostic tests, medication, and total hospitalization costs for pediatric patients with suspected meningitis/encephalitis who received a lumbar puncture (LP) procedure. Related costs were calculated by timing of LP performed and infectious etiology for infants (<1 year) and children (1-17 years). A total of 3030 infants and 3635 children with suspected ME diagnosed between 2011 and 2014 were included in the study. The mean hospitalization cost for infants and children was $12,759 and $11,119, respectively, with medication and laboratory test costs of $834 and $1771 for infants and $825 and $855 for children, respectively. Total visit cost increased with delayed LP procedure, ICU stay, and if the etiology was viral (other than enterovirus or arbovirus) or bacterial. Higher diagnostic and treatment costs were associated with delayed LP procedure, etiologic agent, and ICU stay.