DIAGNOSTIC PERFORMANCE OF CENTRAL NERVOUS SYSTEM INFECTIONS IN PATIENTS WITH NEUROSURGICAL INTENSIVE CARE USING METAGENOMIC NEXT-GENERATION SEQUENCING: A PROSPECTIVE OBSERVATIONAL STUDY.

ABSTRACT: Background. Identifying the causative pathogens of central nervous system infections (CNSIs) is crucial, but the low detection rate of traditional culture methods in cerebrospinal fluid (CSF) has made the pathogenic diagnosis of CNSIs a longstanding challenge. Patients with CNSIs after neurosurgery often overlap with inflammatory and bleeding. Metagenomic next-generation sequencing (mNGS) has shown some benefits in pathogen detection. This study aimed to investigate the diagnostic performance of mNGS in the etiological diagnosis of CNSIs in patients after neurosurgery. Methods. In this prospective observational study, we enrolled patients with suspected CNSIs after neurosurgical operations who were admitted to the intensive care unit of Beijing Tiantan Hospital. All enrolled patients' CSF was tested using mNGS and pathogen culture. According to comprehensive clinical diagnosis, the enrolled patients were divided into CNSIs group and non-CNSIs group to compare the diagnostic efficiency of mNGS and pathogen culture. Results. From December 2021 to March 2023, 139 patients were enrolled while 66 in CNSIs group and 73 in non-CNSIs. The mNGS exceeded culture in the variety and quantity of pathogens detected. The mNGS outperformed traditional pathogen culture in terms of positive percent agreement (63.63%), accuracy (82.01%), and negative predictive value (75.00%), with statistically significant differences ( P < 0.05) for traditional pathogen culture. The mNGS also detected bacterial spectrum and antimicrobial resistance genes. Conclusions. Metagenomics has the potential to assist in the diagnosis of patients with CNSIs who have a negative culture.

Nanopore targeted sequencing-based diagnosis of central nervous system infections in HIV-infected patients.

BACKGROUND: Early and accurate etiological diagnosis is very important for improving the prognosis of central nervous system (CNS) infections in human immunodeficiency virus (HIV)-infected patients. The goal is not easily achieved by conventional microbiological tests. We developed a nanopore targeted sequencing (NTS) platform and evaluated the diagnostic performance for CNS infections in HIV-infected patients, with special focus on cryptococcal meningitis (CM). We compared the CM diagnostic performance of NTS with conventional methods and cryptococcal polymerase chain reaction (PCR). METHODS: This study included 57 hospitalized HIV-infected patients with suspected CNS infections from September 2018 to March 2022. The diagnosis established during hospitalization includes 27 cases of CM, 13 CNS tuberculosis, 5 toxoplasma encephalitis, 2 cytomegalovirus (CMV) encephalitis and 1 Varicella-zoster virus (VZV) encephalitis. The 2 cases of CMV encephalitis also have co-existing CM. Target-specific PCR amplification was used to enrich pathogen sequences before nanopore sequencing. NTS was performed on stored cerebrospinal fluid (CSF) samples and the results were compared with the diagnosis during hospitalization. RESULTS: 53 (93.0%) of the patients were male. The median CD4 cell count was 25.0 (IQR: 14.0-63.0) cells/uL. The sensitivities of CSF culture, India ink staining, cryptococcal PCR and NTS for CM were 70.4% (95%CI: 51.5 - 84.1%), 76.0% (95%CI: 56.6 - 88.5%), 77.8% (59.2 - 89.4%) and 85.2% (95%CI: 67.5 - 94.1%), respectively. All those methods had 100% specificity for CM. Our NTS platform could identify Cryptococcus at species level. Moreover, NTS was also able to identify all the 5 cases of toxoplasma encephalitis, 2 cases of CMV encephalitis and 1 VZV encephalitis. However, only 1 of 13 CNS tuberculosis cases was diagnosed by NTS, and so did Xpert MTB/RIF assay. CONCLUSIONS: NTS has a good diagnostic performance for CM in HIV-infected patients and may have the ability of simultaneously detecting other pathogens, including mixed infections. With continuing improving of the NTS platform, it may be a promising alterative microbiological test for assisting with the diagnosis of CNS infections.

Diagnostic accuracy of inflammatory markers in adults with suspected central nervous system infections.

OBJECTIVES: We aimed to determine diagnostic accuracy of inflammatory markers in plasma and cerebrospinal fluid (CSF) for the diagnosis of central nervous system (CNS) infections and specifically bacterial meningitis. METHODS: We analyzed 12 cytokines, chemokines, and acute phase reactants in CSF and plasma of 738 patients with suspected neurological infection included in a multicenter prospective cohort. We determined diagnostic accuracy for predicting any CNS infection and bacterial meningitis. RESULTS: We included 738 episodes between 2017 and 2022, split into a derivation (n = 450) and validation cohort (n = 288). Of these patients, 224 (30%) were diagnosed with CNS infection, of which 81 (11%) with bacterial meningitis, 107 (14%) with viral meningitis or encephalitis, and 35 patients (5%) with another CNS infection. Diagnostic accuracy of CRP, IL-6, and Il-1ß in CSF was high, especially for diagnosing bacterial meningitis. Combining these biomarkers in a multivariable model increased accuracy and provided excellent discrimination between bacterial meningitis and all other disorders (AUC = 0.99), outperforming all individual biomarkers as well as CSF leukocytes (AUC = 0.97). When applied to the population of patients with a CSF leukocyte count of 5-1000 cells/mm3, accuracy of the model also provided a high diagnostic accuracy (AUC model = 0.97 vs. AUC CSF leukocytes = 0.80) with 100% sensitivity and 92% specificity. These results remained robust in a temporal validation cohort. CONCLUSIONS: Inflammatory biomarkers in CSF are able to differentiate CNS infections and especially bacterial meningitis from other disorders. When these biomarkers are combined, their diagnostic accuracy exceeds that of CSF leukocytes alone and as such these markers have added value to current clinical practice.

A retrospective observational study of 1000 consecutive patients tested with the FilmArray® Meningitis/Encephalitis panel: clinical diagnosis at discharge and microbiological findings.

FilmArray® Meningitis/Encephalitis panel (FAME-p) is used to diagnose central nervous system (CNS) infections. In this study, we investigated performance of FAME-p compared to comparator assays (CA), and for the first time, clinical diagnosis at discharge (CDD). 1000 consecutive patients with a cerebrospinal fluid (CSF) sample analyzed with FAME-p were identified. As CA, culture, polymerase chain reaction and cryptococcal antigen test were used. Medical records of patients were obtained. A CDD of CNS infection was made in 139 of 1000 CSF samples. FAME-p was positive in 66 samples with 44 viral and 22 bacterial agents. Thirteen FAME-p findings were not confirmed by CA, with four discrepant results remaining after comparison with the CDD. Positive percentage agreement (PPA) calculated against CA was 100%. Negative percentage agreement (NPA) calculated against CA was 94.4-99.8% for Haemophilus influenzae, Listeria monocytogenes, Streptococcus agalactiae, S. pneumoniae and varicella-zoster virus (VZV). NPA calculated against CDD was higher (compared to CA) for L. monocytogenes, S. agalactiae and VZV (100%), and lower for Escherichia coli, enterovirus and herpes simplex virus 2 (50-83.3%). NPA of FAME-p for human herpes virus 6 was difficult to interpret. Eighty-four cases received diagnosis of CNS-infection despite negative FAME-p. The four most common non-infectious etiologies were primary headache disorders, cranial nerve palsies, neuroinflammatory disorders and seizure. Although FAME-p shows good performance in diagnosis of CNS infections, result of FAME-p should be interpreted carefully. Considering infectious diseases not covered by FAME-p as well as non-infectious differential diagnoses is important in this context.

Clinical presentation, management, and outcome of suspected central nervous system infections in Indonesia: a prospective cohort study.

BACKGROUND: Little is known about the etiology, clinical presentation, management, and outcome of central nervous system (CNS) infections in Indonesia, a country with a high burden of infectious diseases and a rising prevalence of HIV. METHODS: We included adult patients with suspected CNS infections at two referral hospitals in a prospective cohort between April 2019 and December 2021. Clinical, laboratory, and radiological assessments were standardized. We recorded initial and final diagnoses, treatments, and outcomes during 6 months of follow-up. RESULTS: Of 1051 patients screened, 793 were diagnosed with a CNS infection. Patients (median age 33 years, 62% male, 38% HIV-infected) presented a median of 14 days (IQR 7-30) after symptom onset, often with altered consciousness (63%), motor deficits (73%), and seizures (21%). Among HIV-uninfected patients, CNS tuberculosis (TB) was most common (60%), while viral (8%) and bacterial (4%) disease were uncommon. Among HIV-infected patients, cerebral toxoplasmosis (41%) was most common, followed by CNS TB (19%), neurosyphilis (15%), and cryptococcal meningitis (10%). A microbiologically confirmed diagnosis was achieved in 25% of cases, and initial diagnoses were revised in 46% of cases. In-hospital mortality was 30%, and at six months, 45% of patients had died, and 12% suffered from severe disability. Six-month mortality was associated with older age, HIV, and severe clinical, radiological and CSF markers at presentation. CONCLUSION: CNS infections in Indonesia are characterized by late presentation, severe disease, frequent HIV coinfection, low microbiological confirmation and high mortality. These findings highlight the need for earlier disease recognition, faster and more accurate diagnosis, and optimized treatment, coupled with wider efforts to improve the uptake of HIV services.

Empiric treatment of healthcare-associated central nervous system infections in Denmark: do we need carbapenems?

BACKGROUND: Carbapenems are widely used for empiric treatment of healthcare-associated central nervous system (CNS) infections. We investigated the feasibility of a carbapenem-sparing strategy, utilising a third-generation cephalosporin (ceftriaxone or cefotaxime) (combined with vancomycin) for the empirical treatment of healthcare-associated CNS infections in Eastern Denmark. METHODS: The departments of neurosurgery and neuro-intensive care at Copenhagen University Hospital Rigshospitalet. First, we analysed local microbiological data (1st January 2020-31st August 2022) to identify microorganisms non-susceptible to third-generation cephalosporin. Subsequently, we assessed all carbapenem prescriptions over a three-month period for their indication and justification. RESULTS: In total, 25,247 bacterial cultures were identified, of which 2,563 CNS-related, were included in the analysis. The positivity rate was 10.5% (n = 257/2439) for cerebrospinal-fluid samples and 75.8% (n = 95/124) for brain parenchyma. CNS samples from five individual patients revealed bacteria non-susceptible to third generation cephalosporins (Enterobacter spp. (n = 3), Pseudomonas spp. (n = 2), Klebsiella spp. (n = 2), Citrobacter freundii (n = 1)). All five patients had been hospitalised for ≥10days at the time-point of antibiotic therapy. Out of 11,626 sets of blood cultures, a total of 10 individual patients had Gram-negative blood-stream infections with resistance to ceftriaxone and piperacillin/tazobactam. 140 days-of-therapy (32%) with carbapenem in 18 patients (36%) were definitively or possibly indicated according to guidelines, none were indicated for healthcare-associated CNS-infections. CONCLUSION: An empiric treatment strategy relying on a third-generation cephalosporin appears suitable for healthcare-associated CNS infections at our tertiary hospital, serving a population of 2.6 million. However, in patients with prolonged hospitalization (≥10 days), immunosuppression, prior broad-spectrum antibiotic use, or history of resistant Gram-negative bacteria, empirical prescription of carbapenem may be needed.

Pro-inflammatory cerebrospinal fluid profile of neonates with intraventricular hemorrhage: clinical relevance and contrast with CNS infection.

BACKGROUND: Interpretation of cerebrospinal fluid (CSF) studies can be challenging in preterm infants. We hypothesized that intraventricular hemorrhage (IVH), post-hemorrhagic hydrocephalus (PHH), and infection (meningitis) promote pro-inflammatory CSF conditions reflected in CSF parameters. METHODS: Biochemical and cytological profiles of lumbar CSF and peripheral blood samples were analyzed for 81 control, 29 IVH grade 1/2 (IVH1/2), 13 IVH grade 3/4 (IVH3/4), 15 PHH, 20 culture-confirmed bacterial meningitis (BM), and 27 viral meningitis (VM) infants at 36.5 ± 4 weeks estimated gestational age. RESULTS: PHH infants had higher (p < 0.02) CSF total cell and red blood cell (RBC) counts compared to control, IVH1/2, BM, and VM infants. No differences in white blood cell (WBC) count were found between IVH3/4, PHH, BM, and VM infants. CSF neutrophil counts increased (p ≤ 0.03) for all groups compared to controls except IVH1/2. CSF protein levels were higher (p ≤ 0.02) and CSF glucose levels were lower (p ≤ 0.003) for PHH infants compared to all other groups. In peripheral blood, PHH infants had higher (p ≤ 0.001) WBC counts and lower (p ≤ 0.03) hemoglobin and hematocrit than all groups except for IVH3/4. CONCLUSIONS: Similarities in CSF parameters may reflect common pathological processes in the inflammatory response and show the complexity associated with interpreting CSF profiles, especially in PHH and meningitis/ventriculitis.

The pharmacokinetics/pharmacodynamics of ceftazidime/avibactam for central nervous system infections caused by carbapenem-resistant Gram-negatives: a prospective study.

OBJECTIVES: To describe the pharmacokinetics/pharmacodynamics (PK/PD) of ceftazidime/avibactam in critically ill patients with CNS infections. METHODS: A prospective study of critically ill patients with CNS infections who were treated with ceftazidime/avibactam and the steady-state concentration (Css) of ceftazidime/avibactam in serum and/or CSF was conducted between August 2020 and May 2023. The relationship between PK/PD goal achievement, microbial eradication and the clinical efficacy of ceftazidime/avibactam was evaluated. RESULTS: Seven patients were finally included. The ceftazidime/avibactam target attainment in plasma was optimal for three, quasi-optimal for one and suboptimal for three. In three patients with CSF drug concentrations measured, ceftazidime/avibactam target attainment in CSF was 100% (3/3), which was optimal. The AUCCSF/serum values were 0.59, 0.44 and 0.35 for ceftazidime and 0.57, 0.53 and 0.51 for avibactam. Of the seven patients, 100% (7/7) were treated effectively, 71.4% (5/7) achieved microbiological eradication, 85.7% (6/7) survived and 14.3% (1/7) did not survive. CONCLUSIONS: The limited clinical data suggest that ceftazidime/avibactam is effective in the treatment of CNS infections caused by MDR Gram-negative bacilli (MDR-GNB), can achieve the ideal drug concentration of CSF, and has good blood-brain barrier penetration.

Streptococcus bovis infection of the central nervous system in adults: Report of 4 cases and literature review / Infección del sistema nervioso central por Streptococcus bovis en adultos: reporte de 4 casos y revisión de la literatura

Objectives: To describe the clinical features, history and association with intestinal disease in central nervous system (CNS) S. bovis infections. Methods: Four cases of S. bovis CNS infections from our institution are presented. Additionally a systematic literature review of articles published between 1975 and 2021 in PubMed/MEDLINE was conducted. Results: 52 studies with 65 cases were found; five were excluded because of incomplete data. In total 64 cases were analyzed including our four cases: 55 with meningitis and 9 with intracranial focal infections. Both infections were frequently associated with underlying conditions (70.3%) such as immunosuppression (32.8%) or cancer (10.9%). In 23 cases a biotype was identified, with biotype II being the most frequent (69.6%) and S. pasteurianus the most common within this subgroup. Intestinal diseases were found in 60.9% of cases, most commonly neoplasms (41.0%) and Strongyloides infestation (30.8%). Overall mortality was 17.1%, with a higher rate in focal infection (44.4% vs 12.7%; p=0.001). Conclusions: CNS infections due to S. bovis are infrequent and the most common clinical form is meningitis. Compared with focal infections, meningitis had a more acute course, was less associated with endocarditis and had a lower mortality. Immunosuppression and intestinal disease were frequent in both infections.(AU)

Introducción: Streptococcus bovis, una causa bien conocida de endocarditis asociada a cáncer colorrectal, es también una causa poco frecuente de infecciones del sistema nervioso central (SNC), incluyendo meningitis, abscesos cerebrales o empiema subdural. El objetivo de este estudio es describir las características clínicas, los antecedentes médicos y la asociación con la enfermedad intestinal en las infecciones por S. bovis en el SNC. Métodos: Describimos 4 infecciones por S. bovis en el SNC en nuestra Unidad y, a continuación, presentamos una revisión bibliográfica de los artículos publicados entre 1975-2021 en PubMed/MEDLINE. Resultados: Se encontraron 52 estudios con 65 casos; 5 se excluyeron por datos incompletos. En total se analizaron 64 casos incluyendo nuestros 4: 55 con meningitis y 9 con infecciones focales intracraneales. Ambas infecciones se asociaron con frecuencia a condiciones subyacentes (70,3%) como la inmunosupresión (32,8%) o el cáncer (10,9%). En 23 casos se identificó un biotipo, siendo el más frecuente el biotipo ii (69,6%), y dentro de ellos, S. pasteurianus. En el 60,9% de los casos se detectaron enfermedades intestinales, siendo las más frecuentes las neoplasias (41,0%) y la infestación por Strongyloides (30,8%). La mortalidad global fue del 17,1%, con una tasa mayor en la infección focal (44,4 frente a 12,7%; p=0,001). Conclusiones: Las infecciones del SNC debidas a S. bovis son poco frecuentes y la forma clínica más común es la meningitis. En comparación con las infecciones focales, la meningitis tiene un curso más agudo, está menos asociada a la endocarditis y tiene una menor mortalidad. La inmunosupresión y la enfermedad intestinal fueron frecuentes en ambas infecciones.(AU)

Listeriosis no gestacional: cambios en frecuencia, formas clínicas y factores pronósticos / Non-perinatal listeriosis: changes in frequency, clinical spectrum and prognostic factors

Introducción: La infección por Listeria monocytogenes es una enfermedad grave que afecta mayoritariamente a personas de edad avanzada e inmunodeprimidos y cuya incidencia está aumentando. En este estudio se analizan los casos de listeriosis en dos hospitales con el fin de estudiar cambios en su incidencia, formas de presentación clínica y posibles factores asociados a mortalidad. Material y métodos: Estudio retrospectivo multicéntrico de pacientes con listeriosis diagnosticada por aislamiento microbiológico entre 1977 y 2021 en dos hospitales universitarios de Madrid. Se recogen variables epidemiológicas, clínicas, estado de inmunodepresión, pruebas complementarias y tratamiento. Se analizan factores asociados a mortalidad. Resultados: Se analizaron 194 casos de listeriosis. La incidencia de listeriosis por ingresos aumentó a lo largo del estudio, con una importante caída del número de casos en 2020. La bacteriemia aislada (37,1%) y la afectación del sistema nervioso central (SNC) (36,6%) fueron las presentaciones más frecuentes. El 21% de los casos tuvo síntomas de gastroenteritis. El 16,5% presentó otras infecciones focales, siendo las más frecuentes peritonitis bacteriana espontánea (8,2%), colecistitis (2,1%), infección respiratoria (1,5%) e infección de prótesis vascular (1,5%). La mortalidad intrahospitalaria fue del 24,7%. Fueron factores independientes asociados a mortalidad al ingreso la edad (odds ratio [OR] 1.027, intervalo de confianza [IC] 95% 1.003-1.056) y la presencia de tumor sólido (OR 3.525, IC 95% 1.652-7.524). Conclusiones: En este estudio se constata un aumento de la incidencia de listeriosis en nuestro medio. Las presentaciones más frecuentes fueron la bacteriemia aislada y la afectación del SNC. La mortalidad intrahospitalaria se asoció a la edad y al diagnóstico de tumor sólido.(AU)

Introduction: Listeria monocytogenes infection is a severe disease affecting mainly aged people and patients with immune depression. The incidence of listeriosis seems to be increasing. In the present study cases of listeriosis from two hospitals are analyzed with the aims of studying changes in its incidence, clinical forms of presentation and possible factors associated with mortality. Methods: Retrospective multicentric study of patients with culture-proven listeriosis in two university hospitals in Madrid between 1977 and 2021. Epidemiological and clinical variables, as well as factors for immune depression, complementary studies and treatments were registered. Factors associated with mortality were analyzed. Results: A total of 194 cases of listeriosis were analyzed. The incidence of listeriosis among in-patients increased through the study period, with a significant drop in the number of cases in 2020. The most common clinical presentations were isolated bacteriemia (37.1%) and central nervous system involvement (CNS) (36.6%). Symptoms of gastroenteritis occurred in 21% of cases. Other focal infections were present in 16.5% of patients, the most frequent were spontaneous bacterial peritonitis (8.2%), cholecystitis (2.1%), respiratory infection (1.5%) and vascular prothesis infection (1.5%). In-hospital mortality was 24.7%. Independent factors associated with mortality at admission were age (odds ratio [OR] 1.027, 95% confidence interval [95% CI]1.003–1.056) and a diagnosis of a solid tumor (OR 3.525, 95% CI1.652–7.524). Conclusions: This study confirms an increasing incidence of listeriosis in our millieu. The most common clinical presentations were isolated bacteriemia and central nervous system involvement. In-hospital mortality was associated with age and the diagnosis of a solid tumor.(AU)

Diagnostic accuracy of clinical and laboratory characteristics in suspected non-surgical nosocomial central nervous system infections.

BACKGROUND: The diagnosis of meningitis in non-surgical hospitalized patients is often difficult and diagnostic accuracy of clinical, laboratory, and radiological characteristics is unknown. AIM: To assess diagnostic accuracy for individual clinical characteristics of patients suspected of non-surgical nosocomial central nervous system (CNS) infections. METHODS: In a prospective multi-centre cohort study in the Netherlands with adults suspected of CNS infections, consecutive patients who underwent a lumbar puncture for the suspicion of a non-surgical nosocomial CNS infection were included. All episodes were categorized into five final clinical diagnosis categories, as reference standard: CNS infection, CNS inflammatory disease, systemic infection, other neurological disease, or non-systemic, non-neurological disease. FINDINGS: Between 2012 and 2022, 114 out of 1275 (9%) patients included in the cohort had suspected non-surgical nosocomial CNS infection: 16 (14%) had a confirmed diagnosis, including four (25%) with bacterial meningitis, nine (56%) with viral CNS infections, two (13%) fungal meningitis, and one (6%) parasitic meningitis. Diagnostic accuracy of individual clinical characteristics was generally low. Elevated CSF leucocyte count had the highest sensitivity (81%; 95% confidence interval (CI): 54-96) and negative predictive value (NPV) (96%; 95% CI: 90-99). When combining the presence of abnormalities in neurological or CSF examination, sensitivity for diagnosing a CNS infection was 100% (95% CI: 79-100) and NPV 100% (95% CI: 78-100). CSF examination changed clinical management in 47% of patients. CONCLUSION: Diagnostic accuracy for individual clinical characteristics was low, with elevated CSF leucocyte count having the highest sensitivity and NPV.

A prospective study of nanopore-targeted sequencing in the diagnosis of central nervous system infections.

Central nervous system (CNS) infections are a leading cause of death in patients. Nanopore-targeted sequencing (NTS) has begun to be used for pathogenic microbial detection. This study aims to evaluate the ability of NTS in the detection of pathogens in cerebrospinal fluid (CSF) through a prospective study. Fifty CSF specimens collected from 50 patients with suspected CNS infections went through three methods including NTS, metagenomic next-generation sequencing (mNGS), and microbial culture in parallel. When there was an inconsistency between NTS results and the results of the mNGS, the 16S rDNA gene was amplified followed by Sanger sequencing to further verify pathogens detected by NTS. Among 50 CSF specimens, 76% were NTS-positive, which is lower than mNGS (94.0%), yet higher than microbial culture (16.0%). The overall validation rate, diagnostic accordance rate (DAR), sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of NTS were 86.7%, 50.0%, 71.0%, 15.8%, 57.9%, and 25.0%, respectively. In the CSF total nucleated cell (TNC) number ≤10 cells/µL, DAR, specificity, and PPV were 20%, 11.1%, and 11.1%, whereas in that with CSF TNC number >10 cells/µL, DAR, sensitivity, specificity, PPV, and NPV were 57.5%, 70.0%, 20.0%, 72.4%, and 18.2%, respectively. Although NTS has a higher microbial detection rate than microbial culture, it should combine CSF TNC result to evaluate the value of NTS for the diagnosis of CNS infections. IMPORTANCE: This study aims to prospectively evaluate the ability of nanopore-targeted sequencing (NTS) in the detection of pathogens in cerebrospinal fluid (CSF). It was the first time combining mNGS and microbial culture to verify the NTS-positive results also using 16S rDNA amplification with Sanger sequencing. Although microbial culture was thought to be the gold standard for pathogens detection and diagnosis of infectious diseases, this study suggested that microbial culture of CSF is not the most appropriate way for diagnosing central nervous system (CNS) infection. NTS should be recommended to be used in CSF for diagnosing CNS infection. When evaluating the value of NTS for diagnosis of CNS infections, the results of CSF TNC should be combined, and NTS-positive result is observed to be more reliable in patients with CSF TNC level >10 cells/µL.

Cerebrospinal fluid metagenomics has greatest added value as a test for Powassan virus among patients in New England with suspected central nervous system infection.

Cerebrospinal fluid (CSF) metagenomic next generation sequencing (mNGS) can detect diverse pathogens in patients with central nervous system infection. Due to its high cost and unclear clinical utility, it is typically reserved for patients with unrevealing routine workups. A multi-center retrospective analysis of real-world CSF mNGS was performed involving orders between 2017 and 2022 at a large New England healthcare system. CSF mNGS was performed 64 times with 17 positive results (27 %). In 11/17 positive samples (65 %), the infectious agent had not been previously detected using routine methods. Arboviruses (n = 8) were the most frequently detected agents, particularly Powassan virus (n = 6). Results changed therapy in 3/64 cases (5 %). Positive results were associated with immunodeficiency (p = 0.06), especially anti-B-cell therapy (p = 0.02), and earlier sample collection (p = 0.06). The association with compromised humoral immunity was stronger in the arbovirus and Powassan virus subgroups (p = 0.001), whose constituents were older than the overall cohort and had higher mortality rates.

Diagnostic performance of metagenomic next-generation sequencing for the detection of pathogens in cerebrospinal fluid in pediatric patients with central nervous system infection: a systematic review and meta-analysis.

BACKGROUND: Detecting pathogens in pediatric central nervous system infection (CNSI) is still a major challenge in medicine. In addition to conventional diagnostic patterns, metagenomic next-generation sequencing (mNGS) shows great potential in pathogen detection. Therefore, we systematically evaluated the diagnostic performance of mNGS in cerebrospinal fluid (CSF) in pediatric patients with CNSI. METHODS: Related literature was searched in the Web of Science, PubMed, Embase, and Cochrane Library. We screened the literature and extracted the data according to the selection criteria. The quality of included studies was assessed by the Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) tool and the certainty of the evidence was measured by the Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) score system. Then, the pooled sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odd's ratio (DOR), and area under the curve (AUC) of the summary receiver operating characteristic curve (sROC) were estimated in Stata Software and MetaDisc. Subgroup analyses were performed to investigate the potential factors that influence the diagnostic performance. RESULTS: A total of 10 studies were included in the meta-analysis. The combined sensitivity was 0.68 (95% confidence interval [CI]: 0.59 to 0.76, I2 = 66.77%, p < 0.001), and the combined specificity was 0.89 (95% CI: 0.80 to 0.95, I2 = 83.37%, p < 0.001). The AUC of sROC was 0.85 (95% CI, 0.81 to 0.87). The quality level of evidence elevated by the GRADE score system was low. CONCLUSIONS: Current evidence shows that mNGS presents a good diagnostic performance in pediatric CNSI. Due to the limited quality and quantity of the included studies, more high-quality studies are needed to verify the above conclusion.

ChatGPT fails challenging the recent ESCMID brain abscess guideline.

BACKGROUND: With artificial intelligence (AI) on the rise, it remains unclear if AI is able to professionally evaluate medical research and give scientifically valid recommendations. AIM: This study aimed to assess the accuracy of ChatGPT's responses to ten key questions on brain abscess diagnostics and treatment in comparison to the guideline recently published by the European Society for Clinical Microbiology and Infectious Diseases (ESCMID). METHODS: All ten PECO (Population, Exposure, Comparator, Outcome) questions which had been developed during the guideline process were presented directly to ChatGPT. Next, ChatGPT was additionally fed with data from studies selected for each PECO question by the ESCMID committee. AI's responses were subsequently compared with the recommendations of the ESCMID guideline. RESULTS: For 17 out of 20 challenges, ChatGPT was able to give recommendations on the management of patients with brain abscess, including grade of evidence and strength of recommendation. Without data prompting, 70% of questions were answered very similar to the guideline recommendation. In the answers that differed from the guideline recommendations, no patient hazard was present. Data input slightly improved the clarity of ChatGPT's recommendations, but, however, led to less correct answers including two recommendations that directly contradicted the guideline, being associated with the possibility of a hazard to the patient. CONCLUSION: ChatGPT seems to be able to rapidly gather information on brain abscesses and give recommendations on key questions about their management in most cases. Nevertheless, single responses could possibly harm the patients. Thus, the expertise of an expert committee remains inevitable.

Evaluating the Impact of the BioFire FilmArray in Childhood Meningitis: An Observational Cohort Study.

BACKGROUND: Multiplex polymerase chain reaction assays have the potential to reduce antibiotic use and shorten length of inpatient stay in children with suspected central nervous system infection by obtaining an early microbiological diagnosis. The clinical impact of the implementation of the BioFire FilmArray Meningitis/Encephalitis Panel on the management of childhood meningitis was evaluated at the John Radcliffe Hospital in Oxford and Children's Health Ireland at Temple Street in Dublin. METHODS: Children who had lumbar punctures performed as part of a septic screen were identified retrospectively through clinical discharge coding and microbiology databases from April 2017 to December 2018. Anonymized clinical and laboratory data were collected. Comparison of antibiotic use, length of stay and outcome at discharge was made with a historical cohort in Oxford (2012-2016), presenting before implementation of the FilmArray. RESULTS: The study included 460 children who had a lumbar puncture as part of an evaluation for suspected central nervous system infection. Twelve bacterial cases were identified on the FilmArray that were not detected by conventional bacterial culture. Bacterial culture identified one additional case of bacterial meningitis, caused by Escherichia coli , which had not been identified on the FilmArray. Duration of antibiotics was shorter in children when FilmArray was used than before its implementation; enterovirus meningitis (median: 4 vs. 5 days), human parechovirus meningitis (median: 4 vs. 4.5 days) and culture/FilmArray-negative cerebrospinal fluid (median: 4 vs. 6 days). CONCLUSIONS: The use of a FilmArray can identify additional bacterial cases of meningitis in children that had been negative by traditional culture methods. Children with viral meningitis and culture-negative meningitis received shorter courses of antibiotics and had shorter hospital stays when FilmArray was used. Large studies to evaluate the clinical impact and cost effectiveness of incorporating the FilmArray into routine testing are warranted.

Streptococcus bovis infection of the central nervous system in adults: Report of 4 cases and literature review.

OBJECTIVES: To describe the clinical features, history and association with intestinal disease in central nervous system (CNS) S. bovis infections. METHODS: Four cases of S. bovis CNS infections from our institution are presented. Additionally a systematic literature review of articles published between 1975 and 2021 in PubMed/MEDLINE was conducted. RESULTS: 52 studies with 65 cases were found; five were excluded because of incomplete data. In total 64 cases were analyzed including our four cases: 55 with meningitis and 9 with intracranial focal infections. Both infections were frequently associated with underlying conditions (70.3%) such as immunosuppression (32.8%) or cancer (10.9%). In 23 cases a biotype was identified, with biotype II being the most frequent (69.6%) and S. pasteurianus the most common within this subgroup. Intestinal diseases were found in 60.9% of cases, most commonly neoplasms (41.0%) and Strongyloides infestation (30.8%). Overall mortality was 17.1%, with a higher rate in focal infection (44.4% vs 12.7%; p=0.001). CONCLUSIONS: CNS infections due to S. bovis are infrequent and the most common clinical form is meningitis. Compared with focal infections, meningitis had a more acute course, was less associated with endocarditis and had a lower mortality. Immunosuppression and intestinal disease were frequent in both infections.

Characterization and diagnosis spectrum of patients with cerebrospinal fluid pleocytosis.

PURPOSE: There is an overlap in the cerebrospinal fluid (CSF) characteristics of patients presenting with different etiologies of CSF pleocytosis. Here, we characterized patients with CSF pleocytosis treated in a large hospital. METHODS: A retrospective cohort study of 1150 patients with an elevated CSF leukocyte count > 5 cells/µl treated at a university hospital in Germany from January 2015 to December 2017 was performed. Information on clinical presentation, laboratory parameters, diagnosis and outcome was collected. Clinical and laboratory features were tested for their potential to differentiate between bacterial meningitis (BM) and other causes of CSF pleocytosis. RESULTS: The most common etiologies of CSF pleocytosis were CNS infections (34%: 20% with detected pathogen, 14% without), autoimmune (21%) and neoplastic diseases (16%). CSF cell count was higher in CNS infections with detected pathogen (median 82 cells/µl) compared to autoimmune (11 cells/µl, p = 0.001), neoplastic diseases (19 cells/µl, p = 0.01) and other causes (11 cells/µl, p < 0.001). The CHANCE score was developed to differentiate BM from other causes of CSF pleocytosis: Multivariate regression revealed that CSF cell count > 100 cells/µl, CSF protein > 100 mg/dl, CRP > 5 mg/dl, elevated white blood cell count, abnormal mental status and nuchal rigidity are important indicators. The CHANCE score identified patients with BM with high sensitivity (92.1%) and specificity (90.9%) (derivation cohort: AUC: 0.955, validation cohort: AUC: 0.956). CONCLUSION: Overall, the most common causes for CSF pleocytosis include infectious, neoplastic or autoimmune CNS diseases in ~ 70% of patients. The CHANCE score could be of help to identify patients with high likelihood of BM and support clinical decision making.