Novel strategies to diagnose prosthetic or native bone and joint infections.

INTRODUCTION: Bone and Joint Infections (BJI) are medically important, costly and occur in native and prosthetic joints. Arthroplasties will increase significantly in absolute numbers over time as well as the incidence of Prosthetic Joint Infections (PJI). Diagnosis of BJI and PJI is sub-optimal. The available diagnostic tests have variable effectiveness, are often below standard in sensitivity and/or specificity, and carry significant contamination risks during the collection of clinical samples. Improvement of diagnostics is urgently needed. AREAS COVERED: We provide a narrative review on current and future diagnostic microbiology technologies. Pathogen identification, antibiotic resistance detection, and assessment of the epidemiology of infections via bacterial typing are considered useful for improved patient management. We confirm the continuing importance of culture methods and successful introduction of molecular, mass spectrometry-mediated and next-generation genome sequencing technologies. The diagnostic algorithms for BJI must be better defined, especially in the context of diversity of both disease phenotypes and clinical specimens rendered available. EXPERT OPINION: Whether interventions in BJI or PJI are surgical or chemo-therapeutic (antibiotics and bacteriophages included), prior sensitive and specific pathogen detection remains a therapy-substantiating necessity. Innovative tests for earlier and more sensitive and specific detection of bacterial pathogens in BJI are urgently needed.

The Effects of Social Distancing Policies on Non-SARS-CoV-2 Respiratory Pathogens.

BACKGROUND: The initial focus of the US public health response to coronavirus disease 2019 (COVID-19) was the implementation of numerous social distancing policies. While COVID-19 was the impetus for imposing these policies, it is not the only respiratory disease affected by their implementation. This study aimed to assess the impact of social distancing policies on non-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) respiratory pathogens typically circulating across multiple US states. METHODS: Linear mixed-effect models were implemented to explore the effects of 5 social distancing policies on non-SARS-CoV-2 respiratory pathogens across 9 states from January 1 through May 1, 2020. The observed 2020 pathogen detection rates were compared week by week with historical rates to determine when the detection rates were different. RESULTS: Model results indicate that several social distancing policies were associated with a reduction in total detection rate, by nearly 15%. Policies were associated with decreases in pathogen circulation of human rhinovirus/enterovirus and human metapneumovirus, as well as influenza A, which typically decrease after winter. Parainfluenza viruses failed to circulate at historical levels during the spring. The total detection rate in April 2020 was 35% less than the historical average. Many of the pathogens driving this difference fell below the historical detection rate ranges within 2 weeks of initial policy implementation. CONCLUSIONS: This analysis investigated the effect of multiple social distancing policies implemented to reduce transmission of SARS-CoV-2 on non-SARS-CoV-2 respiratory pathogens. These findings suggest that social distancing policies may be used as an impactful public health tool to reduce communicable respiratory illness.

Identification of bacterial co-detections in COVID-19 critically Ill patients by BioFire® FilmArray® pneumonia panel: a systematic review and meta-analysis.

Among critically ill COVID-19 patients, bacterial coinfections may occur, and timely appropriate therapy may be limited with culture-based microbiology due to turnaround time and diagnostic yield challenges (e.g. antibiotic pre-exposure). We performed a systematic review and meta-analysis of the impact of BioFire® FilmArray® Pneumonia Panel in detecting bacteria and clinical management among critically ill COVID-19 patients admitted to the ICU. Seven studies with 558 patients were included. Antibiotic use before respiratory sampling occurred in 28-79% of cases. The panel incidence of detections was 33% (95% CI 0.25 to 0.41, I2=32%) while culture yielded 18% (95% CI 0.02 to 0.45; I2=93%). The panel was associated with approximately a 1 and 2 day decrease in turnaround for identification and common resistance targets, respectively. The panel may be an important tool for clinicians to improve antimicrobial use in critically ill COVID-19 patients.

Considerations for Assessment and Deployment of Rapid Antigen Tests for Diagnosis of Coronavirus Disease 2019.

Diagnostic testing is a critical tool to mitigate the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic, but molecular testing capacity remains limited. Rapid diagnostic tests (RDTs) that detect SARS-CoV-2 protein antigens (Ag) offer the potential to substantially expand testing capacity and to allow frequent, large-scale, population screening. Testing is simple, rapid (results generally available within 15 minutes), and applicable for diagnosis at point of care. However, implementation of Ag RDTs requires a detailed understanding of test performance and operational characteristics in each testing scenario and population being evaluated. Successful implementation of Ag RDTs on a large scale should combine testing with technical oversight and with clinical and public health infrastructure, and will require production at levels much higher than presently possible. In this commentary, we provide detailed considerations for Ag RDT assessment and use cases to encourage and enable broader manufacturing and deployment.

To Test, Perchance to Diagnose: Practical Strategies for Severe Acute Respiratory Syndrome Coronavirus 2 Testing.

Testing for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in symptomatic and asymptomatic patients is an important component of the multifaceted approach of managing the coronavirus disease 2019 pandemic. Determining how to best define testing strategies for different populations and incorporating these into broader infection prevention programs can be complex. Many circumstances are not addressed by federal, local, or professional guidelines. This commentary describes various scenarios in which testing of symptomatic or asymptomatic individuals for SARS-CoV-2 virus (antigen or ribonucleic acid) can be of potential benefit. Consideration to pretest probability, risks of testing (impact of false-positive or false-negative results), testing strategy, as well as action based on test results are explored. Testing, regardless of setting, must be incorporated into overarching infection control plans, which include use of personal protective equipment (eg, masks), physically distancing, and isolation when exposure is suspected.

Multinational evaluation of the BioFire® FilmArray® Pneumonia plus Panel as compared to standard of care testing.

This study compared standard of care testing (SOC) to BioFire® FilmArray® Pneumonia plus Panel (PNplus). PNplus detects 15 bacteria with semiquantitative log bin values, 7 antibiotic resistance markers, three atypical bacteria (AB), and eight viral classes directly from bronchoalveolar lavage-like specimens (BLS) and sputum-like specimens (SLS). Fifty-two laboratories from 13 European countries and Israel tested 1234 BLS and 1242 SLS with PNplus and SOC. Detection rates and number of pathogens/samples were compared for PNplus pathogens. PNplus bin values and SOC quantities were compared. Three thousand two hundred sixty-two bacteria in PNplus were detected by PNplus and/or SOC. SOC detected 57.1% compared to 95.8% for PNplus (p ≤ 0.0001). PNplus semiquantitative bin values were less than SOC, equal to SOC, or greater than SOC in 5.1%, 25.4%, and 69.6% of results, respectively. PNplus bin values were on average ≥ 1 log than SOC values (58.5% 1-2 logs; 11.0% 3-4 logs). PNplus identified 98.2% of MRSA and SOC 55.6%. SOC detected 73/103 AB (70.9%) and 134/631 viruses (21.2%). PNplus detected 93/103 AB (90.3%) and 618/631 viruses (97.9%) (p ≤ 0.0001). PNplus and SOC mean number of pathogens/samples were 1.99 and 1.44, respectively. All gram-negative resistance markers were detected. PNplus and SOC results were fully or partially concordant for 49.1% and 26.4% of specimens, respectively. PNplus was highly sensitive and detected more potential pneumonia pathogens than SOC. Semiquantification may assist in understanding pathogen significance. As PNplus generates results in approximately 1 h, PNplus has potential to direct antimicrobial therapy in near real time and improve antimicrobial stewardship and patient outcomes.

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.

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

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

Enterovirus D68 outbreak detection through a syndromic disease epidemiology network.

BACKGROUND: In 2014, enterovirus D68 (EV-D68) was responsible for an outbreak of severe respiratory illness in children, with 1,153 EV-D68 cases reported across 49 states. Despite this, there is no commercial assay for its detection in routine clinical care. BioFire® Syndromic Trends (Trend) is an epidemiological network that collects, in near real-time, deidentified. BioFire test results worldwide, including data from the BioFire® Respiratory Panel (RP). OBJECTIVES: Using the RP version 1.7 (which was not explicitly designed to differentiate EV-D68 from other picornaviruses), we formulate a model, Pathogen Extended Resolution (PER), to distinguish EV-D68 from other human rhinoviruses/enteroviruses (RV/EV) tested for in the panel. Using PER in conjunction with Trend, we survey for historical evidence of EVD68 positivity and demonstrate a method for prospective real-time outbreak monitoring within the network. STUDY DESIGN: PER incorporates real-time polymerase chain reaction metrics from the RPRV/EV assays. Six institutions in the United States and Europe contributed to the model creation, providing data from 1,619 samples spanning two years, confirmed by EV-D68 gold-standard molecular methods. We estimate outbreak periods by applying PER to over 600,000 historical Trend RP tests since 2014. Additionally, we used PER as a prospective monitoring tool during the 2018 outbreak. RESULTS: The final PER algorithm demonstrated an overall sensitivity and specificity of 87.1% and 86.1%, respectively, among the gold-standard dataset. During the 2018 outbreak monitoring period, PER alerted the research network of EV-D68 emergence in July. One of the first sites to experience a significant increase, Nationwide Children's Hospital, confirmed the outbreak and implemented EV-D68 testing at the institution in response. Applying PER to the historical Trend dataset to determine rates among RP tests, we find three potential outbreaks with predicted regional EV-D68 rates as high as 37% in 2014, 16% in 2016, and 29% in 2018. CONCLUSIONS: Using PER within the Trend network was shown to both accurately predict outbreaks of EV-D68 and to provide timely notifications of its circulation to participating clinical laboratories.

Economic analysis of rapid multiplex polymerase chain reaction testing for meningitis/encephalitis in adult patients.

PURPOSE: Many patients with suspected meningitis do not require hospitalization yet are admitted, often resulting in unnecessary care and additional cost. We assessed the possible economic impact of a rapid multiplex test for suspected adult community-acquired meningitis/encephalitis. METHODS: A model simulated diagnosis, clinical decisions, resource use/costs of standard of care (SOC) and two cerebrospinal fluid (CSF) testing strategies using the FDA-cleared BioFire® FilmArray® System (FA) which provides results in approximately one hour. RESULTS: Pathogens detected by FA caused approximately 74% of cases, 97% of which would be accurately diagnosed with FA. False positives and false negatives more often led to extended/unnecessary admission than inappropriate discharge/missed admission. Mean cost per case ranged from 16829 to 20791. A strategy of testing all suspected cases yielded greater savings (2213/case) than testing only those with abnormal CSF (812/case) and both were less expensive than SOC. CONCLUSION: This economic analysis demonstrates that FA can inform more appropriate clinician decisions resulting in cost savings with greater economic benefits achievable with syndromic testing of all cases, rather than SOC or targeted syndromic testing.

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.

Epidemiology of Meningitis and Encephalitis in Infants and Children in the United States, 2011-2014.

BACKGROUND: Large epidemiologic studies evaluating the etiologies, management decisions and outcomes of infants and children with meningitis and encephalitis in the United States are lacking. METHODS: Children 0-17 years of age with meningitis or encephalitis as assessed by International Classification of Diseases, Ninth Revision, codes available in the Premier Healthcare Database during 2011-2014 were analyzed. RESULTS: Six thousand six hundred sixty-five patients with meningitis or encephalitis were identified; 3030 (45.5%) were younger than 1 year of age, 295 (4.4%) were 1-2 years of age, 1460 (21.9%) were 3-9 years of age, and 1880 (28.2%) were 10-17 years of age. Etiologies included enterovirus (58.4%), unknown (23.7%), bacterial (13.0%), noninfectious (3.1%), herpes simplex virus (1.5%), other viruses (0.7%), arboviruses (0.5%) and fungal (0.04%). The majority of patients were male [3847 (57.7%)] and healthy [6094 (91.4%)] with no reported underlying conditions. Most underwent a lumbar puncture in the emergency department [5363 (80%)] and were admitted to the hospital [5363 (83.1%)]. Antibiotic therapy was frequent (92.2%) with children younger than 1 year of age with the highest rates (97.7%). Antiviral therapy was less common (31.1%). Only 539 (8.1%) of 6665 of patients received steroids. Early administration of adjunctive steroids was not associated with a reduction in mortality (P = 0.266). The overall median length of stay was 2 days. Overall mortality rate (0.5%) and readmission rates (<1%) was low for both groups. CONCLUSION: Meningitis and encephalitis in infants and children in the United States are more commonly caused by viruses and are treated empirically with antibiotic therapy and antiviral therapy in a significant proportion of cases. Adjunctive steroids are used infrequently and are not associated with a benefit in mortality.

Practical Guidance for Clinical Microbiology Laboratories: Viruses Causing Acute Respiratory Tract Infections.

Respiratory viral infections are associated with a wide range of acute syndromes and infectious disease processes in children and adults worldwide. Many viruses are implicated in these infections, and these viruses are spread largely via respiratory means between humans but also occasionally from animals to humans. This article is an American Society for Microbiology (ASM)-sponsored Practical Guidance for Clinical Microbiology (PGCM) document identifying best practices for diagnosis and characterization of viruses that cause acute respiratory infections and replaces the most recent prior version of the ASM-sponsored Cumitech 21 document, Laboratory Diagnosis of Viral Respiratory Disease, published in 1986. The scope of the original document was quite broad, with an emphasis on clinical diagnosis of a wide variety of infectious agents and laboratory focus on antigen detection and viral culture. The new PGCM document is designed to be used by laboratorians in a wide variety of diagnostic and public health microbiology/virology laboratory settings worldwide. The article provides guidance to a rapidly changing field of diagnostics and outlines the epidemiology and clinical impact of acute respiratory viral infections, including preferred methods of specimen collection and current methods for diagnosis and characterization of viral pathogens causing acute respiratory tract infections. Compared to the case in 1986, molecular techniques are now the preferred diagnostic approaches for the detection of acute respiratory viruses, and they allow for automation, high-throughput workflows, and near-patient testing. These changes require quality assurance programs to prevent laboratory contamination as well as strong preanalytical screening approaches to utilize laboratory resources appropriately. Appropriate guidance from laboratorians to stakeholders will allow for appropriate specimen collection, as well as correct test ordering that will quickly identify highly transmissible emerging pathogens.

Automated Real-Time Collection of Pathogen-Specific Diagnostic Data: Syndromic Infectious Disease Epidemiology.

BACKGROUND: Health care and public health professionals rely on accurate, real-time monitoring of infectious diseases for outbreak preparedness and response. Early detection of outbreaks is improved by systems that are comprehensive and specific with respect to the pathogen but are rapid in reporting the data. It has proven difficult to implement these requirements on a large scale while maintaining patient privacy. OBJECTIVE: The aim of this study was to demonstrate the automated export, aggregation, and analysis of infectious disease diagnostic test results from clinical laboratories across the United States in a manner that protects patient confidentiality. We hypothesized that such a system could aid in monitoring the seasonal occurrence of respiratory pathogens and may have advantages with regard to scope and ease of reporting compared with existing surveillance systems. METHODS: We describe a system, BioFire Syndromic Trends, for rapid disease reporting that is syndrome-based but pathogen-specific. Deidentified patient test results from the BioFire FilmArray multiplex molecular diagnostic system are sent directly to a cloud database. Summaries of these data are displayed in near real time on the Syndromic Trends public website. We studied this dataset for the prevalence, seasonality, and coinfections of the 20 respiratory pathogens detected in over 362,000 patient samples acquired as a standard-of-care testing over the last 4 years from 20 clinical laboratories in the United States. RESULTS: The majority of pathogens show influenza-like seasonality, rhinovirus has fall and spring peaks, and adenovirus and the bacterial pathogens show constant detection over the year. The dataset can also be considered in an ecological framework; the viruses and bacteria detected by this test are parasites of a host (the human patient). Interestingly, the rate of pathogen codetections, on average 7.94% (28,741/362,101), matches predictions based on the relative abundance of organisms present. CONCLUSIONS: Syndromic Trends preserves patient privacy by removing or obfuscating patient identifiers while still collecting much useful information about the bacterial and viral pathogens that they harbor. Test results are uploaded to the database within a few hours of completion compared with delays of up to 10 days for other diagnostic-based reporting systems. This work shows that the barriers to establishing epidemiology systems are no longer scientific and technical but rather administrative, involving questions of patient privacy and data ownership. We have demonstrated here that these barriers can be overcome. This first look at the resulting data stream suggests that Syndromic Trends will be able to provide high-resolution analysis of circulating respiratory pathogens and may aid in the detection of new outbreaks.

Cost of managing meningitis and encephalitis among adult patients in the United States of America.

OBJECTIVE: To determine the associated costs related to the diagnosis and treatment of meningitis and encephalitis (ME) in adult patients in the USA. METHODS: A retrospective observational study design was used to assess the use and costs of diagnostic tests and antimicrobial treatment and the total hospitalization costs for adult patients with suspected ME, who received a lumbar puncture procedure during an emergency department visit or during the first two service days of an inpatient stay. Related costs were calculated by timing of lumbar puncture performed and infectious etiology. RESULTS: A total 26429 adult patients with suspected ME diagnosed between 2011 and 2014 were included in the study. The mean hospitalization cost was $15 572±27168, with antimicrobial medication cost of $1144±4052 and laboratory test cost of $210±244. The total visit cost increased with delayed lumbar puncture procedure, intensive care unit stay, and if the etiology was fungi, arbovirus, or bacteria. CONCLUSIONS: Higher diagnostic and treatment costs are associated with a delayed lumbar puncture procedure, the etiological agent, and the requirement for an intensive care unit stay.

Economic analysis of rapid multiplex polymerase chain reaction testing for meningitis/encephalitis in pediatric patients.

AIM: We assessed the possible economic impact of a rapid test in pediatric patients with suspected community-acquired meningitis/encephalitis. MATERIALS & METHODS: Modeling simulated diagnosis, clinical decisions, resource use/costs of standard of care (SOC) and two cerebrospinal fluid testing strategies using FilmArray® (FA), a US FDA-cleared system that provides results in approximately 1 h. RESULTS: Pathogens detected by FA caused approximately 75% of cases, 97% of which would be accurately diagnosed with FA.  Mean cost/case ranged from $17,599 to $22,025.  Syndromic testing is less expensive than SOC. Testing all suspected cases yielded greater savings ($3481/case) than testing only those with abnormal cerebrospinal fluid ($2157/case). CONCLUSION: Greater economic benefits are achievable with syndromic testing of all cases, rather than SOC or targeted syndromic testing.

Epidemiology of Meningitis and Encephalitis in the United States, 2011-2014.

BACKGROUND: Large epidemiological studies evaluating the etiologies, management decisions, and outcomes of adults with meningitis or encephalitis in the United States (US) are lacking. METHODS: Adult patients (≥18 years) with meningitis or encephalitis by International Classification of Diseases, Ninth Revision codes available in the Premier Healthcare Database during 2011-2014 were analyzed. RESULTS: A total of 26429 patients with meningitis or encephalitis were identified. The median age was 43 years; 53% were female. The most common etiology was enterovirus (13463 [51.6%]), followed by unknown (4944 [21.4%]), bacterial meningitis (3692 [14.1%]), herpes simplex virus (2184 [8.3%]), noninfectious (921 [3.5%]), fungal (720 [2.7%]), arboviruses (291 [1.1%]), and other viruses (214 [0.8%]). Empiric antibiotics, antivirals, and antifungals were administered in 85.8%, 53.4%, and 7.8%, respectively, and varied by etiologies. Adjunctive steroids were utilized in 15.9% of all patients and in 39.3% of patients with pneumococcal meningitis, with an associated decrease in mortality (6.67% vs 12.5%, P = .0245). The median length of stay was 4 days, with the longest duration in those with fungal (13), arboviral (10), and bacterial meningitis (7). Overall inpatient mortality was 2.9% and was higher in those with bacterial (8.2%), fungal (8.2%), or arboviral (8.9%) disease. Overall readmission rate at 30 days was 3.2%; patients with arboviral (12.7%), bacterial (6.7%), and fungal (5.4%) etiologies had higher rates. CONCLUSIONS: Viruses are the most common cause of meningitis and encephalitis in the United States and are treated with antibiotic therapy in the majority of cases. Adjunctive steroid treatment is underutilized in pneumococcal meningitis, where it has shown to decrease mortality.

Maintaining Life-saving Testing for Patients With Infectious Diseases: Infectious Diseases Society of America, American Society for Microbiology, and Pan American Society for Clinical Virology Recommendations on the Regulation of Laboratory-developed Tests.

In 2014, the US Food and Drug Administration (FDA) proposed to regulate laboratory-developed tests (LDTs)-diagnostics designed, manufactured, and used within a single laboratory. The Infectious Diseases Society of America, the American Society for Microbiology, and the Pan American Society for Clinical Virology recognize that the FDA is committed to protecting patients. However, our societies are concerned that the proposed regulations will limit access to testing and negatively impact infectious diseases (ID) LDTs. In this joint commentary, our societies discuss why LDTs are critical for ID patient care, hospital infection control, and public health responses. We also highlight how the FDA's proposed regulation of LDTs could impair patient access to life-saving tests and stifle innovation in ID diagnostics. Finally, our societies make specific recommendations for the FDA's consideration to reduce the burden of the proposed new rules on clinical laboratories and protect patients' access to state-of-the art, quality LDTs.