Cerebrospinal Fluid Of Children Research Articles

Ubiquity of Synthetic Phenolic Antioxidants in Children's Cerebrospinal Fluid from South China: First Evidence for Their Penetration across the Blood-Cerebrospinal Fluid Barrier.

Synthetic phenolic antioxidants (SPAs) and relevant transformation products (TPs) are potentially neurotoxic pollutants to which humans are widely exposed. However, their penetration behavior across the brain barrier and associated exposure to the central nervous system (CNS) remain unknown. This study is the first to investigate a wide range of 30 SPAs and TPs, including emerging SPAs, in matched serum and cerebrospinal fluid (CSF) samples from children in Guangzhou, China. Sixty-two children of either sex aged <14 years with nonbloody CSF and complete clinical information were included. The findings demonstrated the ubiquitous occurrence of many SPAs and TPs, particularly BHT, 2,4-di-tert-butylphenol (DBP), AO 1010, AO 1076, BHT-Q, and BHT-quinol, not only in serum but also in the CSF. Median total concentrations of SPAs and TPs were up to 22.0 and 2.63 ng/mL in serum and 14.5 and 2.11 ng/mL in CSF, respectively. On calculating the penetration efficiencies across the blood-CSF barrier (BCSFB) (RCSF/serum, CCSF/Cserum) for selected SPAs and TPs, their RCSF/serum values (median 0.52-1.41) were highly related to their physicochemical properties, indicating that passive diffusion may be the potential mechanism of BCSFB penetration. In addition, the RCSF/serum values were positively correlated with the barrier permeability index RAlb (AlbuminCSF/Albuminserum), indicating that barrier integrity is an important determinant of BCSFB penetration. Overall, these results will improve our perception of human internal exposure to SPAs and lay a solid foundation for assessing the risk of CNS exposure to various SPAs.

Distribution of Bevacizumab into the Cerebrospinal Fluid of Children and Adolescents with Recurrent Brain Tumors.

To date, evidence has been lacking regarding bevacizumab pharmacokinetics in the cerebrospinal fluid (CSF). This study assessed the penetration of bevacizumab, as part of a metronomic antiangiogenic treatment regimen, into the CSF of children, adolescents, and young adults with recurrent brain tumors. Serum and CSF concentrations, malignant cells, and vascular endothelial growth factor A (VEGF-A) were analyzed in 12 patients (5-27 years) following 10 mg/kg bevacizumab intravenous biweekly administration (EudraCT number 2009-013024-23). A population pharmacokinetic model including body weight, albumin, and tumor type as influential factors was extended to quantify the CSF penetration of bevacizumab. Apart from in serum (minimum concentration/maximum concentration [Cmin/Cmax] 77.0-305/267-612 mg/L, median 144/417mg/L), bevacizumab could be quantified in the CSF (0.01-2.26mg/L, median 0.35 mg/L). The CSF/serum ratio was 0.16 and highly variable between patients. Malignant cells could be detected in CSF before initiation of treatment in five of 12 patients; after treatment, the CSF was cleared in all patients. VEGF-A was detected in three patients before treatment (mean ± SD: 20 ± 11 pg/mL), and was still measurable in one of these patients despite treatment (16 pg/mL). This pharmacokinetic pilot study indicated penetration of bevacizumab into the CSF in a population of children, adolescents, and young adults with recurrent brain tumors.

Neurofilament Light Chain Concentration in Cerebrospinal Fluid in Children with Acute Nontraumatic Neurological Disorders.

(1) Introduction: This pilot study aimed to analyze neurofilament light chain levels in cerebrospinal fluid (cNfL) in a cohort of children with different acute nontraumatic neurological conditions. (2) Methods: This prospective observational cohort study consisted of 35 children aged 3 months to 17 years and was performed from November 2017 to December 2019. Patients' clinical data were reviewed, and patients were assigned to the following groups: n = 10 (28.6%) meningitis, 5 (14.3%) Bell's palsy, 7 (20.0%) febrile non-CNS infection, 3 (8.6%) complex febrile seizure, 4 (11.4%) idiopathic intracranial hypertension, and 6 (17.1%) others. cNfL levels were measured using a sensitive single-molecule array assay. (3) Results: The cNfL levels [median (range)] in children with meningitis were 120.5 pg/mL (58.1-205.4), in Bell's palsy 88.6 pg/mL (48.8-144.5), in febrile non-CNS infection 103.9 pg/mL (60.1-210.8), in complex febrile seizure 56 pg/mL (53.2-58.3), and in idiopathic intracranial hypertension 97.1 pg/mL (60.1-124.6). Within the meningitis group, children with Lyme neuroborreliosis (LNB) had significantly higher cNfL concentrations (median 147.9 pg/mL; range 87.8-205.4 pg/mL) than children with enterovirus meningitis (72.5 pg/mL; 58.1-95.6 pg/mL; p = 0.048) and non-significantly higher cNfL levels when compared to Bell's palsy (88.6 pg/mL; 48.8-144.5 pg/mL; p = 0.082). There was no correlation between cNfL levels and age. (4) Conclusions: Although the number of patients in this pilot study cohort is limited, higher cNfL levels in children with LNB compared to those with viral meningitis (significant) and Bell's palsy (trend) may indicate the potential of cNfL as a biomarker in the differential diagnosis of pediatric meningitis and facial palsy.

Hybrid capture shotgun sequencing detected unexpected viruses in the cerebrospinal fluid of children with acute meningitis and encephalitis

PurposeInvestigation of undiagnosed cases of infectious neurological diseases, especially in the paediatric population, remains a challenge. This study aimed to enhance understanding of viruses in CSF from children with clinically diagnosed meningitis and/or encephalitis (M/ME) of unknown aetiology using shotgun sequencing enhanced by hybrid capture (HCSS).MethodsA single-centre prospective study was conducted at Sant Joan de Déu University Hospital, Barcelona, involving 40 M/ME episodes of unknown aetiology, recruited from May 2021 to July 2022. All participants had previously tested negative with the FilmArray Meningitis/Encephalitis Panel.HCSS was used to detect viral nucleic acid in the patients’ CSF. Sequencing was performed on Illumina NovaSeq platform. Raw sequence data were analysed using CZ ID metagenomics and PikaVirus bioinformatics pipelines.ResultsForty episodes of M/ME of unknown aetiology in 39 children were analysed by HCSS. A significant viral detection in 30 CSF samples was obtained, including six parechovirus A, three enterovirus ACD, four polyomavirus 5, three HHV-7, two BKV, one HSV-1, one VZV, two CMV, one EBV, one influenza A virus, one rhinovirus, and 13 HERV-K113 detections. Of these, one sample with BKV, three with HHV-7, one with EBV, and all HERV-K113 were confirmed by specific PCR. The requirement for Intensive Care Unit admission was associated with HCSS detections.ConclusionThis study highlights HCSS as a powerful tool for the investigation of undiagnosed cases of M/ME. Data generated must be carefully analysed and reasonable precautions must be taken before establishing association of clinical features with unexpected or novel virus findings.

Quantification of meropenem in serum and cerebrospinal fluid in children with bacterial meningitis with augmented renal clearance by UPLC–MS/MS

Meropenem is an ultrabroad-spectrum antimicrobial agent that is often recommended for the treatment of bacterial meningitis (BM) in children. However, a subtherapeutic phenomenon occurred in BM children complicated with augmented renal clearance (ARC) at the recommended dose of meropenem. To support its pharmacokinetics, a sensitive, fast and robust ultra-liquid chromatography–tandem mass spectrometry (UPLC–MS/MS) method was developed to measure meropenem concentrations in serum and cerebrospinal fluid (CSF). The method involved protein precipitation, and samples were diluted with a large proportion of water to eliminate solvent effects. The separation of samples was performed on a Waters Acquity™ BEH C18 column (2.1 × 50 mm i.d., 1.7 μm) with a gradient profile. The mobile phases were formic acid–water (1:1000, v/v) and acetonitrile. The linear range was good, with a concentration range of 0.100–100 μg/mL for serum and 0.0400–20.0 μg/mL for CSF. The intra-day and inter-day precisions were less than 8.0%, and the intra-day and inter-day accuracies varied −6.6% from 6.5% for the both serum and CSF. The selectivity, carry-over, dilution integrity, matrix effect, recovery and stability were validated according to international guidelines. The developed UPLC–MS/MS method successfully determined the meropenem concentrations in the serum and CSF of children with BM complicated with ARC. The results indicated that under the recommended dosing regimen (40 mg/kg every 8 h), the time to reach the effective treatment target of 50%T > MIC was only approximately 3 h and lower CSF concentrations of meropenem were observed in children with BM with ARC.

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

Background and aimsIdentifying 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.

Study of nusinersen metabolites in cerebrospinal fluid of children with spinal muscular atrophy using ultra-high-performance liquid chromatography coupled with quadrupole-time-of-flight mass spectrometry

The study aimed to analyze nusinersen metabolites in the cerebrospinal fluid samples using ion-pair reversed-phase ultrahigh-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry. Three different sample preparation methods were...

Evaluation of Biological Markers in Children's Cerebrospinal Fluid with Bacterial and Viral Meningitis

Background and Aims: Cerebrospinal fluid (CSF) and blood biomarkers are widely evaluated as diagnostic tools to distinguish between bacterial meningitis and viral meningitis in emergency laboratory tests. So, this aimed to examine the levels of diagnostic parameters in blood and CSF to discriminate between bacterial and viral meningitis in young children referred to Khoy Hospital.&#x0D; Materials and Methods: A total of 101 young children with meningitis were enrolled in this prospective study. The diagnosis of bacterial and viral meningitis was based on clinical features and laboratory findings.&#x0D; Results: Of the 101 patients with meningitis, 18 (17.82%) were bacterial, and 83 (82.17%) were viral meningitis. The levels of CSF glucose and CSF/blood glucose ratio were significantly lower in the bacterial meningitis group than in the viral meningitis group (p &lt; 0.01). In contrast, white blood cells count, CSF protein, interleukin-6, C-reactive protein, and ferritin levels were significantly higher in patients with bacterial meningitis compared to viral meningitis (p &lt; 0.01). However, there was no difference between viral and bacterial meningitis groups concerning mean serum glucose.&#x0D; Conclusion: This study suggests that decreased CSF glucose and CSF/blood glucose ratio and increased white blood cells count, CSF protein, ferritin, interleukin-6, and C-reactive protein combined with clinical symptoms can help better diagnosis of bacterial meningitis, especially in comparison with viral meningitis.

Molecular Identification and Detection of Streptococcus pneumoniae Serotypes Isolated from the Cerebrospinal Fluid of Children with Suspected Meningitis: First Report From Alborz, Iran

Background: Pneumococcus causes various infections, some of which are life-threatening, including pneumonia, meningitis, otitis media, bacteremia, and sinusitis. Currently, more than 95 serotypes have been identified. Objectives: The purpose of this study was to isolate and determine Streptococcus pneumoniae serotypes from the cerebrospinal fluid (CSF) of children with suspected meningitis using the multiplex polymerase chain reaction (PCR) method. Materials and Methods: A total of 864 CSF samples were taken from children with suspected meningitis who were admitted to Imam Ali Hospital of Karaj for one year (January 2019 to January 2020). To collect positive S. pneumonia samples, the lytA gene was traced using specific primers and PCR techniques. Results: The results of this study indicated that only 16 patients have a pneumococcal infection (1.85%), of whom 50% have encapsulated pneumococci. Furthermore, serotypes 38 (12.5%), 7F (12.5%), 23F (25%), and 6A/B (50%) were the most common serotypes causing invasive pneumococcal infections in the included samples. Conclusion: Among the techniques for serotyping S. pneumoniae, the multiplex PCR technique is known as a fast, easy, and low-cost method that can serotype a large number of samples. The results also showed that the 13-valent pneumococcal conjugate vaccine can cover at least 50% of the strains that cause invasive pneumococcal diseases (IPDs), which are life-threatening, especially in children. Therefore, it is suggested that the healthcare administrators of Iran design and implement a public vaccination program.

Metabolomics of cerebrospinal fluid reveals prognostic biomarkers in pediatric status epilepticus.

Status epilepticus (SE) is the most common neurological emergency in pediatric patients. This study aimed to screen for prognostic biomarkers of SE in the cerebrospinal fluid (CSF) using metabolomics. Ultra-performance liquid chromatography quadrupole time-of-flight tandem mass spectrometry (UPLC-QTOF-MS) was conducted to identify prognostic biomarkers in CSF metabolomics by comparing the poor outcome group (N = 13) with the good outcome group (N = 15) of children with SE. Differentially expressed metabolites were identified using Mann-Whitney U test corrected by Benjamini-Hochberg and partial least squares discriminant analysis (PLS-DA). The PLS-DA model identified and validated significant metabolic differences between the poor and good outcome groups of children with SE (PLS-DA with R2 Y = 0.992 and Q2 = 0.798). A total of 49 prognosis-related metabolites were identified. Of these metabolites, 20 including glutamyl-glutamine, 3-iodothyronamine, and L-fucose had an area under the curve (AUC) ≥ 80% in prognostic prediction of SE. The logistic regression model combining glutamyl-glutamine and 3-iodothyronamine produced an AUC value of 0.976, with a sensitivity of 0.863 and specificity of 0.956. Pathway analysis revealed that dysregulation of the citrate cycle (TCA) and arginine biosynthesis may contribute to poor SE prognosis. This study highlighted the prognosis-related metabolomic disturbances in the CSF of children with SE and identified potential prognostic biomarkers. A prognostic prediction model combining glutamyl-glutamine and 3-iodothyronamine with high predictive value was established.

Characterization of cerebrospinal fluid (CSF) microbiota at the time of initial surgical intervention for children with hydrocephalus.

To characterize the microbiota of the cerebrospinal fluid (CSF) from children with hydrocephalus at the time of initial surgical intervention. CSF was obtained at initial surgical intervention. One aliquot was stored in skim milk-tryptone-glucose-glycerol (STGG) medium and the second was unprocessed; both were then stored at -70°C. Bacterial growth for CSF samples stored in STGG were subsequently characterized using aerobic and anaerobic culture on blood agar and MALDI-TOF sequencing. All unprocessed CSF samples underwent 16S quantitative polymerase chain reaction (qPCR) sequencing, and a subset underwent standard clinical microbiological culture. CSF with culture growth (either after storage in STGG or standard clinical) were further analyzed using whole-genome amplification sequencing (WGAS). 11/66 (17%) samples stored in STGG and 1/36 (3%) that underwent standard clinical microbiological culture demonstrated bacterial growth. Of the organisms present, 8 were common skin flora and 4 were potential pathogens; only 1 was also qPCR positive. WGAS findings and STGG culture findings were concordant for only 1 sample, identifying Staphylococcus epidermidis. No significant difference in time to second surgical intervention was observed between the STGG culture-positive and negative groups. Using high sensitivity methods, we detected the presence of bacteria in a subset of CSF samples at the time of first surgery. Therefore, the true presence of bacteria in CSF of children with hydrocephalus cannot be ruled out, though our findings may suggest these bacteria are contaminants or false positives of the detection methods. Regardless of origin, the detection of microbiota in the CSF of these children may not have any clinical significance.

&lt;i&gt;Acinetobacter baumannii&lt;/i&gt; in blood-borne and central nervous system infections in intensive care unit children: molecular and genetic characteristics and clinical significance

Acinetobacter baumannii is a representative of the peak priority nosocomial pathogens capable of causing infections with high mortality and economic treatment costs. The purpose of our study was to determine a role of A. baumannii in blood-borne and central nervous system infections in children. We conducted a retrospective study of A. baumannii associated cases of bacteremia and CNS infection in children. A. baumannii strains were isolated from 17 children followed up with surgical pathology (congenital heart defects 24%, abdominal pathology 29%, severe combined trauma 29%) and with somatic diseases accompanied by antibacterial and/or glucocorticosteroid therapy 18%. The minimum inhibitory concentrations of antibiotics were determined by the broth microdilution method. Carbapenemase genes were detected by real time polymerase chain reaction. Biofilm formation genes were determined by PCR. Biofilms were grown using flat-bottomed polystyrene tablets, followed by coloring, fixation, elution and detection. Population diversity was assessed by the multilocus sequence typing. About a quarter of cases of bacteremia and central nervous system infection caused by A. baumannii had an unfavorable outcome. Resistance to carbapenems, aminoglycosides, fluoroquinolones was more than 70%. Carbapenemases of the OXA-23 (24%) and OXA-40 (41%) groups were identified. The study of biofilm production showed that A. baumannii isolates formed biofilms of varying intensity: weak biofilms (59%), moderate (35%) and strong (6%). During determining the sensitivity to meropenem for biofilm and planktonic forms of cultures, it was determined that the minimum inhibitory concentrations of meropenem were significantly higher for biofilms than for planktonic forms. The minimum inhibitory concentrations of meropenem for plankton cells ranged from 0.5 to 512 mg/l. While in biofilms the same microorganisms had in vitro minimum inhibitory concentrations of meropenem within 128 to 512 mg/l and higher. All isolates bore biofilm formation regulating genes: bfmR, bap and katE. The ompA gene was found in 94% strains, and the csuA/B gene was found in 88%. The population pattern of A. baumannii isolated from blood and cerebrospinal fluid of children was represented by nine different sequence types. Most of the isolates were represented by genotypes: ST944Oxf, ST1550Oxf, ST1104Oxf belonging to the international clonal line ICL6, and ST450Oxf, ST2063Oxf and ST1102Oxf of the international clonal line ICL2. Blood-borne and central nervous system infections associated with A. baumannii have a great importance in clinical practice. This microorganism is able to persist for a long time on biotic and abiotic surfaces, has a wide natural and acquired antibiotics resistance.

Children with severe enterovirus A71 infection

BackgroundThere are few reports on the timing of onset and the symptoms of enterovirus A71 (EV-A71) infection, which can easily be misdiagnosed. This study aimed to explore the clinical characteristics of children with severe EV-A71 infection.MethodsThis retrospective observational study included children with severe EV-A71 infection admitted to Hebei Children’s Hospital between January 2016 and January 2018.ResultsA total of 101 patients were included: 57 males (56.4%) and 44 females (43.6%). They were 1–13 years of age. The symptoms were fever in 94 patients (93.1%), rash in 46 (45.5%), irritability in 70 (69.3%), and lethargy in 56 (55.4%). There were 19 (59.3%) patients with abnormal neurological magnetic resonance imaging [pontine tegmentum (n = 14, 43.8%), medulla oblongata (n = 11, 34.4%), midbrain (n = 9, 28.1%), cerebellum and dentate nucleus (n = 8, 25.0%), basal ganglia (n = 4, 12.5%), cortex (n = 4, 12.5%), spinal cord (n = 3, 9.3%), and meninges (n = 1, 3.1%)]. There was a positive correlation between the ratio of neutrophil count and white blood cell count in cerebrospinal fluid in the first 3 days of the disease (r = 0.415, P < 0.001).ConclusionThe clinical symptoms of EV-A71 infection are fever and/or skin rash, irritability, and lethargy. Some patients have abnormal neurological magnetic resonance imaging. The white blood cell count in the cerebrospinal fluid of children with EV-A71 infection may increase alongside neutrophil counts.

Biotin accounts for less than half of all biotin and biotin metabolites in the cerebrospinal fluid of children

Background:Biotin is likely transported into cerebral spinal fluid (CSF) via one or more specific transporters. Concentrations of biotin in CSF measured by using modern analytic techniques that are specific for biotin and biotin metabolites have not previously been reported. Objectives:We aimed to accurately measure the concentration of biotin and major biotin metabolites, biotin sulfoxide (BSO) and bisnorbiotin (BNB), in the CSF of children. Design:Concentrations of biotin were determined initially as total avidin-binding substances (TABS) in CSF obtained by lumbar puncture from 55 children. Biotin, BSO, and BNB were quantitated by HPLC and an avidin-binding assay in CSF samples from a subset of 11 children. Results:Concentrations of TABS in CSF averaged 1.6 nmol/L with substantial variability (SD = 1.3 nmol/L). CSF concentrations of biotin and biotin analogs varied widely, but substantial amounts of BSO were detected in every sample. Biotin accounted for 42 ± 16%, BSO for 41 ± 12%, and BNB for 8 ± 14% of the total. It was surprising that the molar sum of biotin, BSO, and BNB on average was >200-fold the TABS concentrations from the same CSF sample. Using several analytic approaches, we found no masking of detection, nor did we find degradation of biotin or BSO. Gel electrophoresis and streptavidin Western blot detected several biotinylated proteins in CSF. Conclusions:Biotin appears to be bound to protein covalently, reversibly, or both, and this binding likely accounts for the increase in detectable biotin after HPLC. Protein-bound biotin may play an important role in biotin nutriture of the brain.

Prospective, Cross-Sectional Study Finds No Common Viruses in Cerebrospinal Fluid of Children with Pseudotumor Cerebri

Pseudotumor cerebri (PTC) in children is a rare condition whose underlying cause remains largely unknown. No study has yet systematically examined viral infection as a cause of PTC. The current study aimed to characterize PTC in children and investigate the possible role of acute viral infection of the central nervous system in its pathogenesis. A prospective, cross-sectional study was conducted in three centers in Israel. Participants were 50 children aged 0.5-18 years, of whom 27 had a definitive diagnosis of pseudotumor cerebri (the study group) and 23 comprised a control. Data collected included clinical presentation, imaging, treatment, ophthalmic findings, and cerebrospinal fluid (CSF) analysis. Using the ALLPLEXTM meningitis panel, real-time polymerase chain reaction (PCR) was used to test for the presence of 12 common viruses. PTC patients (mean age 12 ± 4.3 years; 14 males, 13 females) had mean opening pressure of 41.9 ±10.2 mmH2O. All PTC patients had papilledema, and 25 (93%) had PTC symptoms. No viruses were found in the PTC group, while in the control group, one patient tested positive for Epstein-Barr virus and another for human herpesvirus type 6. Overall, in our study, PTC was not found to be associated with the presence of viruses in CSF.

Mitochondrial diseases mimicking autoimmune diseases of the CNS and good response to steroids initially.

Neuroimmunological diseases such as autoimmune encephalitis (AE) or acquired demyelinating syndromes (ADS), can present with neurological symptoms and imaging features that are indistinguishable from mitochondrial diseases (MD) in particular at initial presentation. Retrospective analysis of the clinical, laboratory and neuroimaging features of five patients who presented with signs of a neuroimmunological disease but all had pathological pathogenic variants in genes related to mitochondrial energy metabolism. Four patients presented with an acute neurological episode reminiscent of a possible AE and one patient with a suspected ADS at initial presentation. MRI findings were compatible with neuroimmunological diseases in all patients. In two children cerebrospinal fluid (CSF) studies revealed a mildly elevated cell count, two had elevated CSF lactate, none had oligoclonal bands (OCBs). All patients improved rapidly with intravenous steroids or immunoglobulins. Four patients had one or more relapses. Three patients showed worsening of their neurological symptoms with subsequent episodes and one patient died. Relapses in conjunction with new and progressive neurological symptoms, led to additional work-up which finally resulted in different genetic diagnosis of MD in all patients (MT-TL1, MT-ND5, APOA1-BP, HPDL, POLG). We would like to draw attention to a subset of patients with MD initially presenting with signs and symptoms mimicking neuroimmunological. Absence of CSF pleocytosis, elevated CSF lactate and progressive, relapsing course should trigger further (genetic) investigations in search of a MD even in patients with good response initially to immunomodulating therapies.

Characterization of &lt;i&gt;Pseudomonas aeruginosa&lt;/i&gt; isolated from positive samples of hemocultures and cerebrospinal fluid of children

Introduction. Infections of the bloodstream and central nervous system (CNS) caused by Pseudomonas aeruginosa are associated with a serious patient conditions and are often accompanied by high mortality.Aim. Molecular genetic characterization of P. aeruginosa isolated from positive samples of blood cultures and cerebrospinal fluid of patients under 18 years of age from intensive care units of hospitals.Materials and methods. We conducted a retrospective study of bacteremia and CNS infection cases associated with P. aeruginosa from 2014 to 2021. 24 clinical isolates of P. aeruginosa from positive blood cultures and CSF were analyzed. MICs of antibiotics were determined by serial microdilution in broth. Identification of the genes of carbapenemase was carried out using real-time PCR. Virulence genes were determined by PCR. Population diversity was assessed by MLST.Results. More than 70% of isolates showed resistance to carbapenem antibiotics. The phenotype of multiple drug resistance had 25% of the isolates. Extreme resistance was shown by 54% of isolates. The detection rate of metallo-β-lactamases (MBL) was 54%. Based on PCR data, 33% of the strains were found to have the ExoU type, and 67% had the ExoS type. According to MLST, 16 genotypes were identified. The structure was dominated by two sequence types ST654 (29%) and ST235 (12.5%). The structure of patients was dominated by children with surgical pathology — 16 cases, and there were eight somatic patients. Fatal outcome was observed in 28% of cases with bacteremia and CNS infection associated with P. aeruginosa.Conclusion. P. aeruginosa isolates from positive blood cultures and CSF samples are highly resistant to antibiotics; virulence genes were found in all isolates. Strains of high epidemic risk prevailed in the studied sample. More than a quarter of the described clinical cases had an unfavorable outcome.

Evaluation of human bocavirus as well as other well-known viral etiologic agents by PCR in the cerebrospinal fluid of children with clinical impression of viral meningoencephalitis referred to the Children's Medical Center in Tehran, Iran, from 2019 to 2020.

Viral meningoencephalitis is one of the most important diseases that most commonly affect children. In many cases of viral meningoencephalitis, the underlying cause of the disease is not identified, raising the possibility of a variety of pathogens that are not routinely tested. Bocaviruses belong to a newly identified class of viruses that have been reported in some studies to be associated with viral encephalitis. In the present study, we investigated the prevalence of bocaviruses and other viruses in the patients suspected of having viral encephalitis and their associations with various demographic and clinical variables. Two hundred patients with suspected viral meningoencephalitis referred to Children's Medical Center were studied from 2019 to 2020. Age, sex, length of hospitalization, and course of the disease were gathered. Cerebrospinal fluid (CSF) samples were taken from the patients and subjected to biochemical examinations and PCR to identify the underlying cause. Bocaviruses were detected in none of the DNA samples extracted from the CSF specimens. The most identified organisms were mumps and enteroviruses. In 92% of cases, the underlying cause was not identified. PCR-based identification of the underlying causes of viral meningoencephalitis in CSF specimens was not successful in most cases. Bocavirus was not found in any of the collected CSF samples. Further studies are required for drawing more accurate conclusions.

КЛИНИКО-ДИАГНОСТИЧЕСКОЕ ЗНАЧЕНИЕ ЦИТОКИНОВОГО ПРОФИЛЯ В ПЛАЗМЕ КРОВИ И ЛИКВОРЕ У ДЕТЕЙ С ОСТРЫМ ЛИМФОБЛАСТНЫМ ЛЕЙКОЗОМ ПРИ ФОРМИРОВАНИИ ВИНКРИСТИН-ИНДУЦИРОВАННОЙ ПЕРИФЕРИЧЕСКОЙ ПОЛИНЕВРОПАТИИ

Vincristine-induced peripheral neuropath (VIPN) is the main neurotoxic complication in the treatment of acute lymphoblastic leukemia (ALL) in children. The mechanisms for peripheral nerve system injury are not fully understood, rand recent studies have shown the involvement of the immune system. Objective of the study: to determine the cytokine profiles in blood plasma and cerebrospinal fluid in children with ALL and determine their relationship with the formation of VIPN. Materials and methods of research: 65 patients aged 3–17 years with ALL participated in a single-center prospective observational cohort study who underwent chemotherapy treatment according to the ALL-MB-2015 protocol. The patients were divided into two groups based on the severity of VIPN: the 1st group (n=44) – patients with ALL, having neurological manifestations of VIPN, and the 2nd group (n=21) – children with ALL without clinical symptoms of peripheral neuropathy. Levels of cytokines were observed in children’s blood plasma and cerebrospinal fluid by the multiparametric immunofluorescence assay. Results: Comparison of cytokines levels in blood plasma and cerebrospinal fluid represented an increase in CXCL10 (IP-10), CXCL12 (SDF-1α) and stem cells factor (SCF) in the group of children with clinical signs of VIPN. Results suggested statistically significant twofold increase in CXCL10 (IP-10) in blood plasma (p&lt;0,001), an increase in CXCL12 (SDF-1α) in blood plasma and cerebrospinal fluid (p&lt;0.01 and p=0.05, respectively) and SCF in the cerebrospinal fluid (p=0.03). In addition, it was established that a mixed detection of the levels of CXCL10 (IP-10) and CXCL12 (SDF-1α) in blood plasma is highly informative. Conclusion: the results obtained allow us to consider the indications of CXCL10 (IP-10), CXCL12 (SDF-1α) and SCF as biological markers for early diagnosis of VIPN.

MEDB-03. Medulloblastoma cerebrospinal fluid reveals hypoxic indicators (metabolites and lipids) and cancer-specific RNAs

Medulloblastoma (MB) is the most common malignant brain tumor in children. There remains an unmet need for diagnostics to sensitively detect the disease, particularly recurrences. Cerebrospinal fluid (CSF) provides a window into the central nervous system, and liquid biopsy of CSF could provide a relatively non-invasive means for disease diagnosis. There has yet to be an integrated analysis of the transcriptomic, metabolomic, and lipidomic changes occurring in the CSF of children with MB. CSF samples from patients with (n=40) or without (n=11; no cancer) MB were subjected to RNA-sequencing and high-resolution mass spectrometry to identify RNA, metabolite, and lipid profiles. Differentially expressed transcripts, metabolites, and lipids were identified and their biological significance assessed by pathway analysis. Multivariate analysis method DIABLO (R package mixOmics) was used to integrate the molecular changes characterizing the CSF of MB patients. Differentially expressed transcripts, metabolites, and lipids in CSF were discriminatory for the presence of MB but not the exact molecular subtype. One hundred ten genes and ten circular RNAs were differentially expressed in MB CSF compared to normal representing TGF-β signaling, TNF-a signaling via NF-kB, and adipogenesis pathways. Tricarboxylic acid cycle and other metabolites (malate, fumarate, succinate, α-ketoglutarate, hydroxypyruvate, N-acetyl-aspartate) and total triacylglycerols were significantly upregulated in MB CSF compared to normal CSF. Although the transcriptomic, metabolomic, and lipid signatures in CSF to differentiate MB subgroup separation was challenging, we were able to identify a group of omics signatures that could separate cancer from normal CSF. Metabolic and lipidomic profiles both contained indicators of tumor hypoxia. Our approach provides several candidate signatures that deserve further validation, including the novel circular RNA circ_463, and insights into the impact of MB on the CSF microenvironment.