Integrating DNA/RNA microbe detection and host response for accurate diagnosis, treatment and prognosis of childhood infectious meningitis and encephalitis.

BACKGROUND: Infectious meningitis/encephalitis (IM) is a severe neurological disease that can be caused by bacterial, viral, and fungal pathogens. IM suffers high morbidity, mortality, and sequelae in childhood. Metagenomic next-generation sequencing (mNGS) can potentially improve IM outcomes by sequencing both pathogen and host responses and increasing the diagnosis accuracy. METHODS: Here we developed an optimized mNGS pipeline named comprehensive mNGS (c-mNGS) to monitor DNA/RNA pathogens and host responses simultaneously and applied it to 142 cerebrospinal fluid samples. According to retrospective diagnosis, these samples were classified into three categories: confirmed infectious meningitis/encephalitis (CIM), suspected infectious meningitis/encephalitis (SIM), and noninfectious controls (CTRL). RESULTS: Our pipeline outperformed conventional methods and identified RNA viruses such as Echovirus E30 and etiologic pathogens such as HHV-7, which would not be clinically identified via conventional methods. Based on the results of the c-mNGS pipeline, we successfully detected antibiotic resistance genes related to common antibiotics for treating Escherichia coli, Acinetobacter baumannii, and Group B Streptococcus. Further, we identified differentially expressed genes in hosts of bacterial meningitis (BM) and viral meningitis/encephalitis (VM). We used these genes to build a machine-learning model to pinpoint sample contaminations. Similarly, we also built a model to predict poor prognosis in BM. CONCLUSIONS: This study developed an mNGS-based pipeline for IM which measures both DNA/RNA pathogens and host gene expression in a single assay. The pipeline allows detecting more viruses, predicting antibiotic resistance, pinpointing contaminations, and evaluating prognosis. Given the comparable cost to conventional mNGS, our pipeline can become a routine test for IM.

Neutrophil extracellular trap-associated protein in cerebrospinal fluid for prognosis evaluation of adult bacterial meningitis: a retrospective case-control study.

BACKGROUND AND OBJECTIVES: Central nervous system infections, typified by bacterial meningitis, stand as pivotal emergencies recurrently confronted by neurologists. Timely and precise diagnosis constitutes the cornerstone for efficacious intervention. The present study endeavors to scrutinize the influence of inflammatory protein levels associated with neutrophils in cerebrospinal fluid on the prognosis of central nervous system infectious maladies. METHODS: This retrospective case series study was undertaken at the Neurology Department of the Second Hospital of Shandong University, encompassing patients diagnosed with infectious encephalitis as confirmed by PCR testing and other diagnostic modalities spanning from January 2018 to January 2024. The quantification of MPO and pertinent inflammatory proteins within patients' cerebrospinal fluid was accomplished through the utilization of ELISA. RESULTS: We enlisted 25 patients diagnosed with bacterial meningitis, ascertained through PCR testing, and stratified them into two groups: those with favorable prognoses (n = 25) and those with unfavorable prognoses (n = 25). Following assessments for normality and variance, notable disparities in CSF-MPO concentrations emerged between the prognostic categories of bacterial meningitis patients (P < 0.0001). Additionally, scrutiny of demographic data in both favorable and unfavorable prognosis groups unveiled distinctions in CSF-IL-1ß, CSF-IL-6, CSF-IL-8, CSF-IL-18, CSF-TNF-α levels, with correlation analyses revealing robust associations with MPO. ROC curve analyses delineated that when CSF-MPO ≥ 16.57 ng/mL, there exists an 83% likelihood of an adverse prognosis for bacterial meningitis. Similarly, when CSF-IL-1ß, CSF-IL-6, CSF-IL-8, CSF-IL-18, and CSF-TNF-α levels attain 3.83pg/mL, 123.92pg/mL, 4230.62pg/mL, 35.55pg/mL, and 35.19pg/mL, respectively, there exists an 83% probability of an unfavorable prognosis for bacterial meningitis. CONCLUSION: The detection of neutrophil extracellular traps MPO and associated inflammatory protein levels in cerebrospinal fluid samples holds promise in prognosticating bacterial meningitis, thereby assuming paramount significance in the prognostic evaluation of patients afflicted with this condition.

[Streptococcus suis meningitis]. / Meningitis por Streptococcus suis.

Streptococcus suis (S. suis) is a globally prevalent swine pathogen, capable of generating infections in humans who were in contact with the animal or its raw meat. Clinical manifestations range from asymptomatic cases to systemic involvement, with low mortality, but with the possibility of leaving definitive sequelae such as ataxia and hearing loss. There are few case reports, due to lack of knowledge of the disease and its atypical presentation. The objective of this article is to report the case of a man with an occupational history of contact with pigs, who was admitted for meningitis and in whom the isolation of S. suis was obtained in cerebrospinal fluid and paired blood cultures; He completed antibiotic treatment adjusted to bacterial sensitivity, and was left with mild hearing loss as a consequence.

Streptococcus suis (S. suis) es un patógeno porcino prevalente a nivel mundial, capaz de generar infecciones en humanos que estuvieron en contacto con el animal o la carne cruda del mismo. Las manifestaciones clínicas comprenden desde casos asintomáticos hasta compromiso sistémico, con una baja mortalidad, pero con la posibilidad de dejar secuelas definitivas como la ataxia e hipoacusia. Son pocos los reportes de casos, debido al desconocimiento de la enfermedad y a su forma atípica de presentación. El objetivo de este artículo es relatar el caso de un varón con antecedentes ocupacionales de contacto con porcinos, que ingresó por meningitis y en el cual se obtuvo el aislamiento de S. suis en líquido cefalorraquídeo y hemocultivos pareados; completó tratamiento antibiótico ajustado a la sensibilidad bacteriana, quedó con hipoacusia leve como secuela.

Chronic meningitis in adults: a comparison between neurotuberculosis and neurobrucellosis.

BACKGROUND: In regions endemic for tuberculosis and brucellosis, distinguishing between tuberculous meningitis (TBM) and brucella meningitis (BM) poses a substantial challenge. This study investigates the clinical and paraclinical characteristics of patients with TBM and BM. METHODS: Adult patients diagnosed with either TBM or BM who were admitted to two referral hospitals between March 2015 and October 2022, were included, and the characteristics of the patients were analyzed. RESULTS: Seventy patients formed the study group, 28 with TBM and 42 with BM, were included. TBM patients had a 2.06-fold (95% CI: 1.26 to 3.37, P-value: 0.003) higher risk of altered consciousness and a 4.80-fold (95% CI: 1.98 to 11.61, P-value: < 0.001) higher risk of extra-neural involvement as compared to BM patients. Cerebrospinal fluid (CSF) analysis revealed a significantly higher percentage of polymorphonuclear leukocytes (PMN) in TBM compared to BM (Standardized mean difference: 0.69, 95% CI: 0.18 to 1.20, P-value: 0.008). Neuroimaging findings indicated higher risks of hydrocephalus (P-value: 0.002), infarction (P-value: 0.029), and meningeal enhancement (P-value: 0.012) in TBM compared to BM. Moreover, TBM patients had a 67% (95% CI: 21% to 131%, P-value:0.002) longer median length of hospital stay and a significantly higher risk of unfavorable outcomes (Risk ratio: 6.96, 95% CI: 2.65 to 18.26, p < 0.001). CONCLUSIONS: Our study emphasizes that TBM patients displayed increased frequencies of altered consciousness, PMN dominance in CSF, extra-neural involvement, hydrocephalus, meningeal enhancement, and brain infarction. The findings emphasize the diagnostic difficulties and underscore the importance of cautious differentiation between these two conditions to guide appropriate treatment strategies.

The application value of metagenomic next-generation sequencing technology in the diagnosis and treatment of neonatal infectious meningitis - a single center retrospective case-control study.

OBJECTIVE: This retrospective study was conducted to investigate the application value of metagenomics next generation sequencing (mNGS) technology in the diagnosis and treatment of neonatal infectious meningitis. METHODS: From 1 January 2020 to 31 December 2022, 73 newborns suspected of infectious meningitis were hospitalized. After screening by inclusion and exclusion criteria, 69 newborns were subsequently included in the study, containing 27 cases with positive mNGS result and 42 cases with negative mNGS result. Furthermore, according to the diagnosis of meningitis, mNGS positive group and mNGS negative group were further divided into infectious meningitis with mNGS (+) group (n = 27) and infectious meningitis with mNGS (-) group (n = 26), respectively. RESULTS: (1) Compared with cerebrospinal fluid (CSF) culture, mNGS has better diagnostic value [positive predictive value (PPV) = 100.00% (27/27), negative predictive value (NPV) = 38.10% (16/42), agreement rate = 62.32% (43/69), area under the curve (AUC) = 0.750, 95% confidence interval (CI): 0.636-0.864]. (2) There were significant differences in the onset age, age at first CSF test, CSF leukocyte count, CSF glucose, positive rate of CSF culture, blood leukocyte count, procalcitonin (PCT), C-reaction protein (CRP), age at first mNGS test and adjusting anti-infective medication in the comparison between infectious meningitis with mNGS (+) group and infectious meningitis with mNGS (-) group (p < 0.05). (3) mNGS could help improve the cure rate [crude odds ratio (OR) = 3.393, 95%CI: 1.072-10.737; adjusted OR = 15.580, 95%CI: 2.114-114.798]. CONCLUSION: Compared with classic meningitis detection methods, mNGS has better PPV, NPV, agreement rate, and AUC. mNGS could help improve the cure rate.

Paediatric meningitis in the conjugate vaccine era and a novel clinical decision model to predict bacterial aetiology.

OBJECTIVES: The aims of this study were to assess aetiology and clinical characteristics in childhood meningitis, and develop clinical decision rules to distinguish bacterial meningitis from other similar clinical syndromes. METHODS: Children aged <16 years hospitalised with suspected meningitis/encephalitis were included, and prospectively recruited at 31 UK hospitals. Meningitis was defined as identification of bacteria/viruses from cerebrospinal fluid (CSF) and/or a raised CSF white blood cell count. New clinical decision rules were developed to distinguish bacterial from viral meningitis and those of alternative aetiology. RESULTS: The cohort included 3002 children (median age 2·4 months); 1101/3002 (36·7%) had meningitis, including 180 bacterial, 423 viral and 280 with no pathogen identified. Enterovirus was the most common pathogen in those aged <6 months and 10-16 years, with Neisseria meningitidis and/or Streptococcus pneumoniae commonest at age 6 months to 9 years. The Bacterial Meningitis Score had a negative predictive value of 95·3%. We developed two clinical decision rules, that could be used either before (sensitivity 82%, specificity 71%) or after lumbar puncture (sensitivity 84%, specificity 93%), to determine risk of bacterial meningitis. CONCLUSIONS: Bacterial meningitis comprised 6% of children with suspected meningitis/encephalitis. Our clinical decision rules provide potential novel approaches to assist with identifying children with bacterial meningitis. FUNDING: This study was funded by the Meningitis Research Foundation, Pfizer and the NIHR Programme Grants for Applied Research.

Evaluation of metagenomic and pathogen-targeted next-generation sequencing for diagnosis of meningitis and encephalitis in adults: A multicenter prospective observational cohort study in China.

BACKGROUND: Next-generation sequencing (NGS) might aid in the identification of causal pathogens. However, the optimal approaches applied to cerebrospinal fluid (CSF) for detection are unclear, and studies evaluating the application of different NGS workflows for the diagnosis of intracranial infections are limited. METHODS: In this multicenter, prospective observational cohort study, we described the diagnostic efficacy of pathogen-targeted NGS (ptNGS) and metagenomic NGS (mNGS) compared to that of composite microbiologic assays, for infectious meningitis/encephalitis (M/E). RESULTS: In total, 152 patients diagnosed with clinically suspected M/E at four tertiary hospitals were enrolled; ptNGS and mNGS were used in parallel for pathogen detection in CSF. Among the 89 patients who were diagnosed with definite infectious M/E, 57 and 39 patients had causal microbial detection via ptNGS and mNGS, respectively. The overall accuracy of ptNGS was 65.1%, with a positive percent agreement (PPA) of 64% and a negative percent agreement (NPA) of 66.7%; and the overall accuracy of mNGS was 47.4%, with a PPA of 43.8% and an NPA of 52.4% after discrepancy analysis. There was a significant difference in the detection efficiency between these two methods both for PPA (sensitivity) and overall accuracy for pathogen detection (P < 0.05). CONCLUSIONS: NGS tests have provided new information in addition to conventional microbiologic tests. ptNGS seems to have superior performance over mNGS for common causative pathogen detection in CSF for infectious M/E.

Central Nervous System Antimicrobial Exposure and Proposed Dosing for Anthrax Meningitis.

BACKGROUND: The high mortality of systemic anthrax is likely a consequence of the severe central nervous system inflammation that occurs in anthrax meningitis. Effective treatment of such infections requires, at a minimum, adequate cerebrospinal fluid (CSF) antimicrobial concentrations. METHODS: We reviewed English medical literature and regulatory documents to extract information on serum and CSF exposures for antimicrobials with in vitro activity against Bacillus anthracis. Using CSF pharmacokinetic exposures and in vitro B. anthracis susceptibility data, we used population pharmacokinetic modeling and Monte Carlo simulations to determine whether a specific antimicrobial dosage would likely achieve effective CSF antimicrobial activity in patients with normal to inflamed meninges (ie, an intact to markedly disrupted blood-brain barrier). RESULTS: The probability of microbiologic success at achievable antimicrobial dosages was high (≥95%) for ciprofloxacin, levofloxacin (500 mg every 12 hours), meropenem, imipenem/cilastatin, penicillin G, ampicillin, ampicillin/sulbactam, doxycycline, and minocycline; acceptable (90%-95%) for piperacillin/tazobactam and levofloxacin (750 mg every 24 hours); and low (<90%) for vancomycin, amikacin, clindamycin, and linezolid. CONCLUSIONS: Prompt empiric antimicrobial therapy of patients with suspected or confirmed anthrax meningitis may reduce the high morbidity and mortality. Our data support using several ß-lactam-, fluoroquinolone-, and tetracycline-class antimicrobials as first-line and alternative agents for treatment of patients with anthrax meningitis; all should achieve effective microbiologic exposures. Our data suggest antimicrobials that should not be relied on to treat suspected or documented anthrax meningitis. Furthermore, the protein synthesis inhibitors clindamycin and linezolid can decrease toxin production and may be useful components of combination therapy.

Cerebrospinal fluid inflammatory markers to differentiate between neonatal bacterial meningitis and sepsis: A prospective study of diagnostic accuracy.

OBJECTIVES: We evaluated the diagnostic accuracy of cerebrospinal fluid (CSF) inflammatory markers for diagnosing bacterial meningitis in neonates with sepsis and/or meningitis. METHODS: Cases were identified from a prospective multicenter study including patients aged 0-3 months with Group B Streptococcal (GBS) or Escherichia coli culture positive sepsis/meningitis. CSF CXCL10, MDC, IL-6, IL-8, IL-10, TNF- α, MIF, IL-1RA, CXCL13, IL-1ß, CRP and procalcitonin concentrations were measured with Luminex technology. RESULTS: In 61/373 patients (17%) residual CSF from the lumbar puncture was available, of whom 16 (26%) had definitive meningitis, 15 (25%) probable meningitis and 30 (49%) had sepsis. All biomarkers were detectable in CSF and showed significantly higher concentrations in definitive meningitis versus sepsis patients and six biomarkers in probable meningitis versus sepsis patients. Discrimination between definitive meningitis and sepsis was excellent for IL-1RA (area under the receiver operating characteristic curve [AUC] 0.93), TNF-α (AUC 0.92), CXCL10 (AUC 0.90), IL-1ß (AUC 0.92), IL-6 (AUC 0.94), IL-10 (AUC 0.93) and a combination of IL-1RA, TNF-α, CXCL-10 and CSF leukocyte count (AUC 0.95). CSF leukocyte count remained the predictor with the highest diagnostic accuracy (AUC 0.96). CONCLUSION: CSF inflammatory markers can be used to differentiate between neonatal sepsis and meningitis.

Enhancing sensitivity of qPCR assays targeting Streptococcus pneumoniae, Neisseria meningitidis and Haemophilus influenzae by using a mutant Taq DNA polymerase.

AIMS: Streptococcus pneumoniae, Neisseria meningitidis and Haemophilus influenzae are important causes of bacterial meningitis. In this study, the DNA binding site of the wild type Taq DNA polymerase was modified to produce a mutant enzyme with enhanced DNA affinity and PCR performance. The engineered and the wild type enzymes were integrated into qPCR-based assays for molecular detection of S. pneumoniae, N. meningitidis, H. influenzae, and serogroups and serotypes of these three pathogens. METHODS: Bio-Speedy® Bacterial DNA Isolation Kit (Bioeksen R&D Technologies, Turkiye) and 2× qPCR-Mix for hydrolysis probes (Bioeksen R&D Technologies, Turkiye) and CFX96 Instrument (Biorad Inc., USA) were used for all molecular analyses. Spiked negative clinical specimens were tested using the developed qPCR assays and the culture-based conventional methods for the analytical performance evaluation. RESULTS: All qPCR assays did not produce any positive results for the samples spiked with potential cross-reacting bacteria. Limit of detection (LOD) of the assays containing the mutant enzyme was 1 genome/reaction (10 cfu/mL sample) which is at least 3 times lower than the previously reported LOD levels for DNA amplification based molecular assays. LODs for the spiked serum and cerebrospinal fluid (CSF) samples decreased 2.3-4.7 and 1.2-3.5 times respectively when the mutant enzyme was used instead of the wild type Taq DNA polymerase. CONCLUSIONS: It is possible to enhance analytical sensitivity of qPCR assays targeting the bacterial agents of meningitis by using an engineered Taq DNA polymerase. These qPCR-based assays can be used for direct detection and serogrouping / serotyping of S. pneumoniae, N. meningitidis and H. influenzae at concentrations close to the lower limit of medical decision point.

Clinical Characteristics, Treatment, and Outcomes of Veterans with Cerebrospinal Fluid Culture Positive for Gram-Negative Rod Bacteria: A Retrospective Analysis over 18 Years in 125 Veterans Health Administration Hospitals.

Optimal management for patients with bacterial ventriculitis/meningitis due to Gram-negative rods (GNRs) has yet to be well investigated. We assessed the clinical characteristics, treatment, and outcomes of patients with a positive cerebrospinal fluid (CSF) culture for GNRs. We conducted a retrospective cohort study of all patients with a positive CSF culture within the Veterans Health Administration (VHA) system during 2003-2020. Clinical and microbiological characteristics between the true meningitis and contamination groups were compared. Of the 5919 patients with positive CSF cultures among 125 nationwide VHA acute-care hospitals, 297 (5.0%) were positive for GNRs. Among 262 patients analyzed, 156 (59.5%) were assessed as patients with true meningitis, and 106 (40.5%) were assessed as patients with contaminated CSF cultures. Patients with true meningitis had a significantly higher CSF protein (median 168 vs 57 mg/dL, p < 0.001), CSF white blood cell count (median 525 vs 3/µL, p = 0.008) and percentage of neutrophils in CSF (median 88 vs 4%, p < 0.001). Enterobacterales were more common in the true meningitis group, while unidentified GNR or polymicrobial CSF cultures were more common in the contamination group. The all-cause 90-day mortality was 25.0% (39/156) in patients with true meningitis and 10.4% (11/106) in those with contaminated CSF cultures. None of the 11 patients with contaminated CSF cultures who died were considered due to missed meningitis. More than 40% of patients with a positive CSF culture with GNR did not receive treatment without negative consequences. Careful clinical judgment is required to decide whether to treat such patients.

Development and validation of a novel multiplex digital PCR assay for identification of pathogens in cerebrospinal fluid of children with bacterial meningitis.

BACKGROUND AND AIMS: Identifying the pathogens of bacterial meningitis (BM) is crucial for its diagnosis and treatment. The aim of this study is to develop and validate a novel method for detecting pathogens in cerebrospinal fluid (CSF) of children with BM using a digital polymerase chain reaction (dPCR) assay. MATERIALS AND METHODS: A novel multiplex dPCR assay method has been developed and validated. The diagnostic performance of the dPCR assay was compared with that of synchronous CSF culture, and the factors affecting its performance were analyzed. RESULTS: A total of 69 children with BM were enrolled prospectively. The sensitivity of the dPCR assay was 94.44 %, specificity was 100 %, coincidence rate was 98.55 %, Kappa value was 0.959, and net reclassification improvement was 61.11 %. Compared with the CSF culture assay, the dPCR assay had higher sensitivity in different bacterial groups. Multiple factors affected its performance, including previous use of antibiotics, sampling time, BM complications, and levels of inflammatory biomarkers in CSF and blood (all P < 0.05). Patients who required intensive care and died had a higher bacterial DNA loads identified by dPCR assay (both P < 0.05). CONCLUSION: This novel assay has better pathogen detection ability than CSF culture. Its performance was influenced by sampling time, previous use of antibiotics, and disease severity.

Diagnostic and Monitoring Value of ß-2 Transferrin and Transferrin for Intracranial Infection After Neurosurgery.

BACKGROUND AND OBJECTIVES: After neurosurgery, intracranial infection is a common complication with high rates of clinical impairment and death. Traditional diagnostic approaches are time-consuming. Early and correct diagnosis improves infection control, treatment success, and survival. Novel markers are used to diagnose and classify post-neurosurgical meningitis (PNM) to overcome the difficulties of diagnosing postoperative intracranial infections and avoid the drawbacks of existing diagnostic measures. The objective was to investigate the diagnostic value of ß-2 transferrin (ß-2TF) and transferrin (TF) in the cerebrospinal fluid (CSF) for the identification of intracranial infection after neurosurgery. METHODS: Owing to their symptoms and laboratory results, 168 patients with suspected intracranial infection after neurosurgery were divided into 3 groups: post-neurosurgical bacterial meningitis (PNBM; n = 61), post-neurosurgical aseptic meningitis (PNAM; n = 45), and non-PNM (n = 62). We measured lactate (LA), ß-2TF, and TF levels in the CSF. RESULTS: CSF LA levels were significantly higher in the PNM, PNBM, and PNAM groups compared with the non-PNM group ( P < .05). The CSF ß-2TF level in PNM, PNBM, and PNAM were statistically higher than those in non-PNMs ( P < .05). CSF TF levels in the PNBM group were statistically higher than those in the PNAM and non-PNM groups ( P < .05). The PNBM and non-PNM receiver operating curve (ROC) analysis indicates that the cutoff values for the combination (LA, ß-2TF, TF) was 0.349, and the area under the curve (AUC) was 0.945 ( P < .0001), with 92.86% sensitivity and 92.98% specificity. The PNAM and non-PNM ROC analysis indicates that the cutoff values for the combination (LA, ß-2TF, TF) was 0.346, and the AUC was 0.962 ( P < .0001), with 89.29% sensitivity and 90.24% specificity. The PNM and non-PNM ROC analysis indicates that the cutoff values for the combination (LA, ß-2TF, TF) was 0.609, and the AUC was 0.941 ( P < .0001), with 96.36% sensitivity and 82.83% specificity. A Glasgow Coma Scale score ≤8, LA, ß-2TF/TF ratio, length of hospital stay, intensive care unit admission, poor surgical wound, and craniotomy were associated with poor outcomes ( P < .05). LA and ß-2TF were independent risk factors for intracranial infection. CONCLUSION: Postoperative cerebral infections can be identified using CSF ß-2TF as a particular marker protein. CSF TF helps distinguish PNBM from PNAM. Combining CSF LA with them improves diagnostic speed, sensitivity, and accuracy. LA and ß-2TF were independent risk factors for cerebral infection.

Markedly Increased Mean Platelet Volume in Bacterial Meningitis.

BACKGROUND: Differentiating bacterial and viral meningitis is crucial, and this study explored the potential of mean platelet volume (MPV) as a marker for differentiation. METHODS: Blood samples were collected from patients with central nerve system related manifestations, and MPV was tested. Cerebrospinal fluid samples were obtained and bacterial culture and the FilmArray ME panel were performed. The distribution of MPV was compared between groups. RESULTS: The study included 8 patients in the bacterial meningitis group and 12 patients in the viral meningitis group. The bacterial meningitis group showed a significantly higher median MPV of 10.9 (9.2 - 11.6) fL compared to the viral meningitis group with 8.4 (8.1 - 8.8) fL (p < 0.0001). CONCLUSIONS: MPV could serve as a diagnostic indicator to differentiate between bacterial and viral meningitis. Larger studies are needed to validate these findings.

Cerebrospinal Fluid Lactate as a Differential Biomarker for Bacterial and Viral Meningitis.

Meningitis is a critical public health problem demanding immediate diagnosis and effective treatment due to high mortality rates. Cerebrospinal Fluid (CSF) lactate concentration is a promising test to distinguish bacterial from viral meningitis. This study aimed to assess the performance and usefulness of CSF lactate as a biomarker to differentiate between bacterial and viral meningitis, and to determine its optimal level to differentiate between them. This prospective study included 50 patients, presented to Abbassia Fever Hospital with clinical findings consistent with meningitis. Patients were divided into two groups: Group1 included 30 patients with bacterial meningitis. Group 2 included 20 patients with viral meningitis. CSF lactate and other conventional CSF parameters were recorded. For CSF culture, Streptococcus pneumoniae was identified in 53.3% of the bacterial meningitis group. The polymerase chain reaction (PCR) indicated that S. pneumoniae was present in 26/50 (52%) and 3/50 (6%) patients were PCR negative. Among bacterial meningitis patients, S. pneumoniae was the most pervasive organism 26/30 (86.7%). The mean CSF lactate level was 9.3 mmol/l ±5.0 (2.2-17.6). There was a statistically significant strong agreement (Kappa=0.957) between types of meningitis diagnosed by PCR, culture, and CSF lactate at cutoff level of 7.2 mmol/L. This cutoff value was the best to differentiate between bacterial and viral meningitis. The validity of CSF lactate as a differentiating tool showed sensitivity, specificity, positive predictive value, and negative predictive value of 93.3%, 100%, 100%, and 90.9%, respectively. In conclusion, CSF lactate could be a valuable, sensitive, specific, and rapid marker for identifying the most dangerous bacterial causes of CNS infection, especially S. pneumoniae. CSF lactate can be routinely used as an early biochemical warning marker and a useful point-of-care test. CSF lactate at cutoff level of >7.2 mmol/L can accurately detect S. pneumoniae, the most prevalent organism in Egypt.

Clinical variation in the early assessment and management of suspected community-acquired meningitis: a multicentre retrospective study.

BACKGROUND: Bacterial meningitis is a medical emergency and timely management has been shown to improve outcomes. The aim of this study was to compare the early assessment and management of adults with suspected community-onset meningitis between hospitals and identify opportunities for clinical practice improvement. METHODS: This retrospective cohort study was conducted at three principal referral hospitals in Sydney, Australia. Adult patients with suspected meningitis undergoing cerebrospinal fluid sampling between 1 July 2018 and 31 June 2019 were included. Relevant clinical and laboratory data were extracted from the medical record. Differences between sites were analysed and factors associated with time to antimicrobial therapy were assessed by Cox regression. RESULTS: In 260 patients, the median time from triage to antibiotic administration was 332 min with a difference of up to 147 min between hospitals. Median time from triage to lumbar puncture (LP) was 366 min with an inter-hospital difference of up to 198 min. Seventy per cent of patients had neuroimaging prior to LP, and this group had a significantly longer median time to antibiotic administration (367 vs 231 min; P = 0.001). Guideline concordant antibiotics were administered in 84% of patients, with only 39% of those administered adjunctive corticosteroids. Seven (3%) patients had confirmed bacterial meningitis. Modifiable factors associated with earlier antimicrobial administration included infectious diseases involvement (adjusted hazard ratio [aHR], 1.50 [95% confidence interval (CI), 1.01-2.24]) and computed tomography (CT) scanning (aHR, 0.67 [95% CI, 0.46-0.98]). CONCLUSION: Opportunities for improvement include reducing the time to LP and antibiotic administration, improving coadministration of corticosteroids and avoiding potentially unnecessary CT scanning.

Evaluation of the accuracy of multiplex polymerase chain reaction in differentiation between bacterial and viral meningitis.

BACKGROUND: Meningitis is one of the most dangerous infection affecting children. The need for rapid and accurate diagnosis is mandatory for improving the outcome. AIM OF THE WORK: To evaluate the role of multiplex polymerase chain reaction (PCR) in diagnosis of meningitis either bacterial or viral and to detect its accuracy. PATIENTS AND METHODS: A cross-sectional study was carried out in University Children Hospital, Faculty of Medicine, between November 2019 and September 2020. The study was approved by the Ethics Review Board of Faculty of Medicine, Assiut University, and informed written consent was obtained. The committee's reference number is 17200161. Clinicaltrails.gov ID: NCT03387969. Forty-eight children aged 2 to 18 years with meningitis were included. Detailed history and examination, blood glucose level at time of admission prior to lumbar puncture, and multiplex PCR in cerebrospinal fluid (CSF) were evaluated. RESULTS: The mean age of children was 3.27 ± 1.27 years. Thirty-five (72.9%) cases were bacterial meningitis while 13 (27.1%) cases were viral meningitis. Multiplex PCR had 94% sensitivity and 100% specificity for diagnosis of bacterial meningitis. CONCLUSION: Multiplex PCR may help in diagnosis and differentiation of bacterial and viral meningitis with accurate and rapid results.

Simultaneous Late, Late-Onset Group B Streptococcal Meningitis in Identical Twins.

To our knowledge, late, late-onset group B streptococcal (GBS) meningitis in identical twins has yet to be reported. We describe a case of 14-week-old twins who developed fever hours apart and presented simultaneously to the emergency department 2 days later with seizures. Blood and cerebrospinal fluid (CSF) cultures from both infants were positive for GBS. Their clinical courses were highly similar, with magnetic resonance imaging (MRI) demonstrating ventriculitis and subdural empyema, complicated by clinical and subclinical seizures requiring quadruple antiepileptic treatment. The CSF was sterile for both on follow-up lumbar puncture 48 hours after the initial positive CSF culture. Both showed marked improvement on antimicrobial and antiepileptic therapy, with fever resolving after 5 days of therapy, control of seizures, and slowly improving MRI findings. Twin A received a 6-week course of penicillin, whereas twin B received 6 weeks plus an additional 10 days due to persistent left cochlear enhancement consistent with labyrinthitis. Evaluation for an underlying primary immunodeficiency was negative. Genomic analysis revealed that the patients' CSF GBS isolates were essentially identical and of capsular polysaccharide serotype Ia.

Bacterial ribosomal RNA detection in cerebrospinal fluid using a viromics approach.

BACKGROUND: In patients with central nervous system (CNS) infections identification of the causative pathogen is important for treatment. Metagenomic next-generation sequencing techniques are increasingly being applied to identify causes of CNS infections, as they can detect any pathogen nucleic acid sequences present. Viromic techniques that enrich samples for virus particles prior to sequencing may simultaneously enrich ribosomes from bacterial pathogens, which are similar in size to small viruses. METHODS: We studied the performance of a viromic library preparation technique (VIDISCA) combined with low-depth IonTorrent sequencing (median ~ 25,000 reads per sample) for detection of ribosomal RNA from common pathogens, analyzing 89 cerebrospinal fluid samples from patients with culture proven bacterial meningitis. RESULTS: Sensitivity and specificity to Streptococcus pneumoniae (n = 24) before and after optimizing threshold parameters were 79% and 52%, then 88% and 90%. Corresponding values for Neisseria meningitidis (n = 22) were 73% and 93%, then 67% and 100%, Listeria monocytogenes (n = 24) 21% and 100%, then 27% and 100%, and Haemophilus influenzae (n = 18) 56% and 100%, then 71% and 100%. A higher total sequencing depth, no antibiotic treatment prior to lumbar puncture, increased disease severity, and higher c-reactive protein levels were associated with pathogen detection. CONCLUSION: We provide proof of principle that a viromic approach can be used to correctly identify bacterial ribosomal RNA in patients with bacterial meningitis. Further work should focus on increasing assay sensitivity, especially for problematic species (e.g. L. monocytogenes), as well as profiling additional pathogens. The technique is most suited to research settings and examination of idiopathic cases, rather than an acute clinical setting.

Reference range for cerebrospinal fluid values in neonates: 5-year retrospective study.

BACKGROUND: Cerebro spinal fluid (CSF) parameters (white blood cell count, protein, glucose) in the diagnosis of neonatal bacterial meningitis. OBJECTIVES: To report the reference range of CSF parameters (white blood cell count, protein, glucose) in both term and preterm infants. METHODS: This was a single center retrospective study over a period of 5 years (2015-2020). We included infants aged 0-3 months admitted to the neonatal unit and infants ≤28 days attending pediatric acute care and who underwent Lumbar Puncture. We excluded infants with evidence of CSF bacteremia, viral infection and traumatic lumbar puncture defined as CSF Red Blood Cell >500 cells/µL. Clinical, demographic, and microbiological data were collected from the hospital database. The study was approved by ethics committee. RESULTS: We identified a total of 518 CSF samples, with 232 CSF samples available for final analysis. 54% of excluded samples were traumatic. Median birth gestation and birth weight of the study cohort were 38 (IQR 35-40) weeks and 3030 (IQR 1965-3565) grams respectively. Median RBC, WBC count, protein and glucose were 15 (IQR 3-85)/µL, 3(IQR 0-8.5)/µL, 0.72 (0.53-1.06) g/L and 2.8 (2.4-3.3) mmol/L respectively. There was no difference in CSF WBC cell count between preterm and term infants. Higher CSF protein content was noted in preterm infants and infants in the first 7 days of life. Use of antibiotics prior to LP was associated with higher CSF protein. Presence of any CSF RBC (including <500 cells/µL) influenced the CSF WBC count and protein content. CONCLUSION: We have provided a reference range of CSF parameters in neonates without meningitis. CSF WBC count between preterm and term infants were similar with higher CSF protein content in preterm infants and for infants in the first seven days of life. Presence of any CSF RBC influenced CSF parameters.