Metabolomic Characterization of Cerebrospinal Fluid from Intracranial Bacterial Infection Pediatric Patients: A Pilot Study.

Intracranial bacterial infection remains a major cause of morbidity and mortality in neurosurgical cases. Metabolomic profiling of cerebrospinal fluid (CSF) holds great promise to gain insights into the pathogenesis of central neural system (CNS) bacterial infections. In this pilot study, we analyzed the metabolites in CSF of CNS infection patients and controls in a pseudo-targeted manner, aiming at elucidating the metabolic dysregulation in response to postoperative intracranial bacterial infection of pediatric cases. Untargeted analysis uncovered 597 metabolites, and screened out 206 differential metabolites in case of infection. Targeted verification and pathway analysis filtered out the glycolysis, amino acids metabolism and purine metabolism pathways as potential pathological pathways. These perturbed pathways are involved in the infection-induced oxidative stress and immune response. Characterization of the infection-induced metabolic changes can provide robust biomarkers of CNS bacterial infection for clinical diagnosis, novel pathways for pathological investigation, and new targets for treatment.

Cerebrospinal fluid CXLC13 indicates disease course in neuroinfection: an observational study.

BACKGROUND: The chemokine CXCL13 is an intensively investigated biomarker in Lyme neuroborreliosis (LNB). Its role in other neuroinfections is increasingly recognized but less clear. OBJECTIVE: To determine the significance of CXCL13 in established central nervous system (CNS) infections other than LNB by matching cerebrospinal fluid (CSF) CXCL13 elevations with severity of the disease course. METHODS: We investigated 26 patients with bacterial (n = 10) and viral (n = 16; tick-borne encephalitis, n = 6; varicella zoster infection, n = 10) neuroinfections of whom CSF CXCL13 levels were available twice, from lumbar punctures (LP) performed at admission and follow-up. As outcome classification, we dichotomized disease courses into "uncomplicated" (meningitis, monoradiculitis) and "complicated" (signs of CNS parenchymal involvement such as encephalitis, myelitis, abscesses, or vasculitis). CXCL13 elevations above 250 pg/ml were classified as highly elevated. RESULTS: Eight of 26 patients (31%) with both bacterial (n = 4) and viral (n = 4) neuroinfections had a complicated disease course. All of them but only 3/18 patients (17%) with an uncomplicated disease course had CSF CXCL13 elevations > 250 pg/ml at the follow-up LP (p < 0.001). At admission, 4/8 patients (50%) with a complicated disease course and 3/18 patients (17%) with an uncomplicated disease course showed CXCL13 elevations > 250 pg/ml. All four patients with a complicated disease course but only one with an uncomplicated disease course had sustained CXCL13 elevations at follow-up. Patient groups did not differ with regard to age, time since symptom onset, LP intervals, type of infections, and anti-pathogen treatments. CONCLUSION: Our study revealed pronounced CXCL13 elevations in CSF of patients with severe disease courses of bacterial and viral neuroinfections. This observation indicates a role of CXCL13 in the CNS immune defense and points at an additional diagnostic value as biomarker for unresolved immune processes leading to or associated with complications.

Infectious causes and outcomes in patients presenting with cerebral spinal fluid pleocytosis.

To evaluate the infectious etiologies, clinical features, and outcomes of patients with CNS infections at a tertiary care center. Patients that present with a pleocytosis in the cerebral spinal fluid (CSF), defined as a CSF WBC count > 5 cells/mm3, from July 2015 to June 2016 at a tertiary care hospital were analyzed for this report. Data from patients with confirmed (n = 43) and presumed (n = 51) CNS infections were analyzed. CNS infection was the leading known cause of CSF pleocytosis (n = 43, 18% of all patients with a pleocytosis in the CSF), and HSV-2 was identified as the leading causative pathogen (n = 10) followed by varicella zoster virus (n = 5). Fifty-three percent of patients with a pleocytosis in the CSF did not receive a diagnosis. In the patients that did not receive a diagnosis, CNS infection was presumed to be the cause in 51 patients (21% of patients with CSF pleocytosis). The mean time to diagnosis for patients with confirmed CNS infection was 16 days, but time to diagnosis was highly variable depending on the causative pathogen. There was a significant overlap in CSF parameters and peripheral white blood cell counts in patients diagnosed with a viral, bacterial, or fungal infection. Neuroimaging changes were present in only 44% of CNS infections. The overall mortality was 7% for CNS infections, and 17% of patients with a CNS infection had a severe neurologic deficit at presentation while only 3% had a severe deficit at the last neurologic assessment. This study provides new insights into the infectious causes of disease in a cohort of patients with pleocytosis in the CSF. The study provides new insights into the time to diagnosis and outcomes in patients that present with pleocytosis in the CSF.

Evaluation of a Commercial Multiplex Molecular Panel for Diagnosis of Infectious Meningitis and Encephalitis.

Rapid and accurate laboratory tests are important for the timely diagnosis and treatment of central nervous system infections. The FilmArray meningitis/encephalitis (ME) panel (BioFire Diagnostics, Salt Lake City, UT) is an FDA-cleared, multiplex molecular panel that allows the detection of 14 pathogens (bacterial [n = 6], viral [n = 7], and fungal [n = 1] pathogens) from cerebrospinal fluid (CSF). In this study, we evaluated the performance characteristics of the FilmArray ME panel using clinical, residual CSF samples (n = 291) that tested positive by a routine method(s) (e.g., bacterial culture, individual real-time PCR assay) for a pathogen represented on the ME panel. Of note, a subset (n = 76) of the CSF specimens was collected during the prevaccine era and had been characterized as positive for a bacterial pathogen. The FilmArray ME panel demonstrated an overall percent positive agreement (PPA) of 97.5% (78/80) for bacterial pathogens, 90.1% (145/161) for viruses, and 52% (26/50) for Cryptococcusneoformans/C. gattii Despite the low overall agreement (52%) between the ME panel and antigen testing for detection of C. neoformans/C. gattii, the percent positive agreement of the FilmArray assay for C. neoformans/C. gattii was 92.3% (12/13) when the results were compared directly to the results of routine fungal smear or culture. The FilmArray ME panel offers a rapid (∼60-min), syndrome-based approach for the detection of select meningitis and encephalitis pathogens.

Afebrile Infants Evaluated in the Emergency Department for Serious Bacterial Infection.

OBJECTIVES: Afebrile infants 0 to 60 days of age are sometimes evaluated for serious bacterial infection (SBI). Our objective was to describe the clinical and laboratory findings in this population and compare them to their febrile counterparts. METHODS: We performed a retrospective observational study comparing afebrile infants undergoing an SBI evaluation to those evaluated for fever. RESULTS: We included infants who were admitted to the hospital and had at least 2 of 3 following bacterial cultures: blood, urine, or cerebrospinal fluid. Of the 1184 infants presenting to the emergency department with chief complaints that may prompt an SBI evaluation, 579 patients met our inclusion criteria with 362 in the fever group and 217 in the afebrile group. The most common chief complaints in the afebrile group were respiratory symptoms (27%), seizure (22%), vomiting/diarrhea (21%), and apparent life-threatening event (11%). Rates of true-positive blood, urine, and cerebrospinal fluid cultures were 2%, 2.4%, and 0.9% respectively. All cases of bacterial meningitis were in the fever group antibiotics (P = 0.16). Infants with fever were more likely to receive antibiotics (P < 0.001), although there were no statistical differences between the 2 groups in the rates of positive blood or urine cultures. CONCLUSIONS: Afebrile infants make up a significant percentage of SBI evaluations in the emergency department. Respiratory symptoms, vomiting, and seizure-like activity are common presentations. Although rates of bacteremia and urinary tract infection are higher in the febrile group, this did not reach statistical significance, and therefore afebrile infants should still be considered at risk for SBI.

[The use of MALDI-TOF MS for direct identification of bacteria in clinical specimens].

MALDI-TOF MS is a method enabling rapid identification of bacteria. This is also important for early initiation of adequate antibiotic therapy in patients with infections. In this review, various methods for direct detection of bacteria in clinical specimens are described. The fundamental part deals with direct identification of bacteria from positive blood cultures. Attention is also paid to identification of bacteria from urine and cerebrospinal fluid. Finally, reliability of the methods is mentioned in comparison with conventional methods.

Molecular diagnosis of central nervous system opportunistic infections in HIV-infected Zambian adults.

BACKGROUND: Knowledge of central nervous system (CNS) opportunistic infections (OIs) among people living with human immunodeficiency virus (HIV) in sub-Saharan Africa is limited. METHODS: We analyzed 1 cerebrospinal fluid (CSF) sample from each of 331 HIV-infected adults with symptoms suggestive of CNS OI at a tertiary care center in Zambia. We used pathogen-specific primers to detect DNA from JC virus (JCV), varicella zoster virus (VZV), cytomegalovirus (CMV), Epstein-Barr virus (EBV), herpes simplex virus (HSV) types 1 and 2, Mycobacterium tuberculosis, and Toxoplasma gondii via real-time polymerase chain reaction (PCR). RESULTS: The patients' median CD4(+) T-cell count was 89 cells/µL (interquartile range, 38-191 cells/µL). Of 331 CSF samples, 189 (57.1%) had at least 1 pathogen. PCR detected DNA from EBV in 91 (27.5%) patients, M. tuberculosis in 48 (14.5%), JCV in 20 (6.0%), CMV in 20 (6.0%), VZV in 13 (3.9%), HSV-1 in 5 (1.5%), and HSV-2 and T. gondii in none. Fungal and bacteriological studies showed Cryptococcus in 64 (19.5%) patients, pneumococcus in 8 (2.4%), and meningococcus in 2 (0.6%). Multiple pathogens were found in 68 of 189 (36.0%) samples. One hundred seventeen of 331 (35.3%) inpatients died during their hospitalization. Men were older than women (median, 37 vs 34 years; P = .01), more recently diagnosed with HIV (median, 30 vs 63 days; P = .03), and tended to have a higher mortality rate (40.2% vs 30.2%; P = .07). CONCLUSIONS: CNS OIs are frequent, potentially treatable complications of AIDS in Zambia. Multiple pathogens often coexist in CSF. EBV is the most prevalent CNS organism in isolation and in coinfection. Whether it is associated with CNS disease or a marker of inflammation requires further investigation. More comprehensive testing for CNS pathogens could improve treatment and patient outcomes in Zambia.

Antibiotic-impregnated versus silver-bearing external ventricular drainage catheters: preliminary results in a randomized controlled trial.

BACKGROUND: Evaluation of antibiotic-impregnated (AI) and ionized silver particle coated external ventricular drainage catheters (EVD) in patients with subarachnoid (SAH) or intracranial hemorrhage (ICH). METHODS: Between February 2011 and June 2012, 40 patients with acute hydrocephalus due to SAH, ICH or intraventricular hemorrhage were enrolled in a prospective, randomized, mono-center pilot study. Primary endpoints were defined as: number of events of cerebrospinal fluid (CSF) infections. Secondary endpoints were defined as: neurosurgical complications following the placement of the EVD, number of revisions of EVD catheters, and cost effectiveness. RESULTS: Sixty-one EVD placements in 40 patients, 32 antibiotic-coated (Bactiseal(®)), 29 silver-bearing catheters (VentriGuard(®)), have been performed. Confirmed or high suspicion of CSF infections occurred in 11 out of 61 events (confirmed infection: p = 0.71, probable infection: p = 0.90). Revisions of EVD were needed in 13 cases (22 %) due to CSF infection, dysfunction, impaired healing, or malplacement (p = 0.37). CONCLUSION: Regarding CSF infection rate and dysfunction, no statistical significant differences between the two EVD catheters Bactiseal(®) versus VentriGuard(®) were found. The silver-bearing catheter might offer a safe and cost-conscious alternative to the AI catheter.

Rates of positive blood, urine, and cerebrospinal fluid cultures in children younger than 60 days during the vaccination era.

BACKGROUND: Fever is a common reason children present to the emergency department. The goal of this study was to determine the rates and the etiology of bacterial infection in children younger than 2 months during the vaccination era. METHODS: This is a retrospective chart review performed at a tertiary care hospital. Electronic medical records were used to identify patients who had a workup for fever/sepsis in the emergency department. The search was limited to identifying only children younger than 60 days. RESULTS: A total of 207 patients satisfied the inclusion/exclusion criteria. In children younger than 28 days, the blood culture-positive rate was 2.7% (range, 0.0%-6.4%), the urine culture-positive rate was 10.7% (range, 3.5%-17.8%), and the cerebrospinal fluid-positive rate (excluding enteroviral infections) was 0% (range, 0.0%-3.9%). In children 29 to 60 days, the blood culture-positive rate was 1.5% (range, 0.0%-3.6%), urine culture-positive rate was 8.5% (range, 3.7%-13.3%), and the cerebrospinal fluid-positive rate (excluding enteroviral infections) was 1.7% (range, 0.0%-5.0%). Urinary tract infections due to Escherichia coli were very common, whereas no cases of Haemophilus influenzae and one case of Streptococcus pneumoniae were detected. CONCLUSIONS: Urinary tract infections due to E. coli are very common in this age group. The classic pathogens H. influenzae and S. pneumoniae were essentially nonexistent in this study possibly because of herd immunity obtained through current vaccination practices.

Childhood Invasive Bacterial Disease in Kathmandu, Nepal (2005-2013).

BACKGROUND: Invasive bacterial disease (IBD; including pneumonia, meningitis, sepsis) is a major cause of morbidity and mortality in children in low-income countries. METHODS: We analyzed data from a surveillance study of suspected community-acquired IBD in children <15 years of age in Kathmandu, Nepal, from 2005 to 2013 before introduction of pneumococcal conjugate vaccines (PCV). We detailed the serotype-specific distribution of invasive pneumococcal disease (IPD) and incorporated antigen and PCR testing of cerebrospinal fluid (CSF) from children with meningitis. RESULTS: Enhanced surveillance of IBD was undertaken during 2005-2006 and 2010-2013. During enhanced surveillance, a total of 7956 children were recruited of whom 7754 had blood or CSF culture results available for analysis, and 342 (4%) had a pathogen isolated. From 2007 to 2009, all 376 positive culture results were available, with 259 pathogens isolated (and 117 contaminants). Salmonella enterica serovar Typhi was the most prevalent pathogen isolated (167 cases, 28% of pathogens), followed by Streptococcus pneumoniae (98 cases, 16% pathogens). Approximately, 73% and 78% of pneumococcal serotypes were contained in 10-valent and 13-valent PCV, respectively. Most cases of invasive pneumococcal disease (IPD) were among children ≥5 years of age from 2008 onward. Antigen and PCR testing of CSF for pneumococci, Haemophilus influenzae type b and meningococci increased the number of these pathogens identified from 33 (culture) to 68 (culture/antigen/PCR testing). CONCLUSIONS: S. enterica serovar Typhi and S. pneumoniae accounted for 44% of pathogens isolated. Most pneumococcal isolates were of serotypes contained in PCVs. Antigen and PCR testing of CSF improves sensitivity for IBD pathogens.

Increased cytokines/chemokines and hyponatremia as a possible cause of clinically mild encephalitis/encephalopathy with a reversible splenial lesion associated with acute focal bacterial nephritis.

OBJECTIVE: Clinically mild encephalitis/encephalopathy with a reversible splenial lesion (MERS), the second most common encephalopathy syndrome in Japan, is most often associated with viral infection. Bacterial MERS has been rarely reported but is mostly associated with acute focal bacterial nephritis (AFBN) for an unknown reason. We examined cytokines and chemokines in four MERS patients with AFBN to determine if they play an important role in the pathogenesis. METHODS: We examined the clinical charts and MRI results in four MERS patients with AFBN, and measured 10 cytokines and chemokines in serum and cerebrospinal fluid in the acute phase. These were analyzed using the Mann-Whitney U test, compared with the control group (cases with a non-inflammatory neurological disease). Longitudinal changes in the serum cytokine and chemokine levels were evaluated in two patients. RESULTS: Hyponatremia was observed in all four patients with MERS associated with AFBN (128-134 mEq/L). CSF analysis revealed increased cytokines/chemokines associated with Th1 (CXCL10, TNF-α, IFN-γ), T reg (IL-10), Th17 (IL-6), and neutrophil (IL-8 and CXCL1). In serum, upregulation was observed in those associated with Th1 (CXCL10, TNF-α, IFN-γ), Th17 (IL-6), and inflammasome (IL-1ß). The increased serum cytokines/chemokines in the acute stage normalized within 2 weeks in patients 1 and 2, so examined, in accordance with their clinical improvement. CONCLUSION: Increased cytokines/chemokines and hyponatremia may be factors that explain why AFBN is likely to cause MERS.

[Low-manifest infections with CNS damage in patients in prolonged unconscious state of non-inflammatory etiology].

AIM: Study of specter of low-manifest infections (LMI) with central nervous system (CNS) damage and their role in patients in prolonged unconscious state (PUS) of noninflammatory etiology. MATERIALS AND METHODS: 32 patients (23 male, 9 female; age 14-58) in PUS of various etiology were examined. The main group (18 patients) received therapy against all infectious diseases including LMI; control group (14 patients)--only against common and nosocomial microflora. Patients were immunologically, infectologically and neurologically examined in dynamic. The data obtained were treated by using STATISTICA for Windows (version 5.5). RESULTS: Significant differences in immune and infectologic status depending on the nature of primary CNS damage were not detected. Immunodeficiency was detected in all patients; 94% of patients had increased non-specific IgM and IgE. Among LMI agents Chlamydia spp. were predominant. Cultural and/or PCR methods detected this microorganism during the primary examination in cerebrospinal fluid samples in 56% patients and in blood samples in 56%; during the second diagnostics or autopsy--only in 13 and 25%, respectively. Detection of Bacteroides fragilis, Human Herpes Virus (HHV-6), Virus Epstein Barr (VEB), Cytomegalovirus (CMV) in cerebrospinal fluid, blood and on mucous membranes of nasopharynx and conjunctiva was grouped more frequently with the presence of Chlamydia spp. in the CNS (p < 0.05) than with other LMI agents. Sanation of CNS from LMI was significantly accompanied by regeneration of communicative activity in comparison with the control group. CONCLUSION: In patients with PUS high frequency of CNS infection by various LMI agents and primarily Chlamydia spp. should be considered. Sanation from LMI can become a "window" for effective neuro-regenerative treatment.

Impact of the Step-by-Step on febrile infants.

OBJECTIVE: To evaluate the impact of introducing the Step-by-Step approach on care quality in young febrile infants. DESIGN: Observational study including infants ≤90 days old with fever without source seen in a paediatric emergency department 5 years before (n=1222) and after (n=1151) its introduction. Quality of care was evaluated in terms of adherence to recommendations, resource use and safety. RESULTS: Adherence: percentages of infants undergoing both urine and blood tests and infants <15 days old receiving full sepsis evaluation increased (84.7% vs 91.0% and 23.9% vs 63.3%, respectively; p<0.01). Resource use: lumbar puncture and admission rates decreased (24.1% vs 18.7% and 43.6% vs 38.3%, respectively; p<0.01), while the rate of antibiotic therapy increased (30.2% vs 43.2%; p<0.01). SAFETY: the invasive bacterial infection rate among infants managed as outpatients was unchanged (0.7% vs 0.3%; p=0.24). CONCLUSION: The introduction of the Step-by-Step increased the quality of care provided to young febrile infants.

Lactic acid is of low predictive value for the diagnosis of bacterial infection in ventricular cerebrospinal fluid samples containing residual blood.

BACKGROUND: Lactic acid concentrations (LA) are an established marker of bacterial infection in cerebrospinal fluid (CSF). However, use of LA for the detection of infection in CSF with residual blood has not been fully evaluated. METHODS: Analysis of LA and total protein, cell count and bacterial culture were performed in 90 lumbar and ventricular CSF samples contaminated with blood. RESULTS: Bacterial culture was positive in six CSF samples. The diagnostic value of the cell count was significantly higher than that of LA for the prediction of a positive culture, even if all culture positive and all likely infected samples were included in the analysis. There was no significant difference in LA concentrations between positive or likely positive ventricular CSF samples and all negative, ventricular samples. CONCLUSIONS: Although LA concentrations in CSF are evidently a predictor of bacterial infection, its diagnostic value for the detection of bacterial infection in ventricular CSF with residual blood is limited.

Risk factors for cerebrospinal fluid shunt infections during an outbreak: a case-control study.

BACKGROUND: There are few published reports of cerebrospinal fluid (CSF) shunt infection outbreaks. In 2017-2018, British Columbia Children's Hospital (BCCH) experienced an increase in CSF shunt infections co-incident with a move to new operating rooms and a change in shunt catheters used. AIMS: To describe how an outbreak was detected, investigations were undertaken to determine the cause, risk factors associated with CSF shunt infection during the outbreak, and changes implemented to attempt to control the outbreak. METHODS: Retrospective case-control study. Population included patients who underwent new shunt insertion or revision. Univariate logistic regression models were fitted for each of the variables. Associations with P-values <0.2 were considered of potential interest for further investigation. FINDINGS: There were six cases of CSF shunt infection and 19 controls. The causative organism was different in each case. The only risk factors that met the criteria for further investigation were being a neonate at the time of surgery [odds ratio (OR) 9.0, 95% confidence interval (CI) 0.7-125.3, P=0.10] and the presence of gastrointestinal disease (OR 3.8, 95% CI 0.5-26.2, P=0.18). No association was found with the operating room used or the surgical staff. In response to the outbreak, human traffic through the operating rooms was limited, rigid adherence to the wearing of surgical masks was enforced, and return to the previous CSF shunt catheters used was implemented. CONCLUSION: No modifiable risk factors were associated with CSF shunt infection. After implementation of surgical protocol changes, no further cases of CSF shunt infection linked to the outbreak were identified.

When a Root Is the Cause of Infection.

BACKGROUND: Sinorhizobium meliloti is a phytobacterium found in the root nodules of plants, where it is involved in fixing nitrogen for delivery to the roots in exchange for a photosynthate carbon source. There have been no reported cases of S. meliloti infection in humans. We conducted a retrospective review of clinical records and diagnostic tests. CASE DESCRIPTION: An 81-year-old woman who presented to the emergency department with a 1-day history of progressive decline in her level of consciousness following a head injury and deep scalp laceration. Her medical history was significant for a ventriculoperitoneal shunt due to normal pressure hydrocephalus. Imaging studies revealed hydrocephalus and a tear in the shunt catheter. Cerebrospinal fluid analysis was not suggestive for meningitis. Cerebrospinal fluid culture revealed an unfamiliar organism, identified as S. meliloti following sequencing of its entire genome, which was considered a contaminant. The patient subsequently developed peritonitis, and the same pathogen was detected in the peritoneal fluid, suggesting distal shunt infection. Symptoms resolved after shunt removal and antibiotic treatment. Thorough history taking revealed that the patient had fallen and struck her head against a flowerpot. CONCLUSIONS: S. meliloti is a phytopathogen that should not be easily disregarded as a contaminant when isolated from human sterile fluids or tissues. Aggressive management including removal of infected hardware, if present, is required to ensure resolution of infection. It emphasizes the importance of thorough history taking.

Higher Procalcitonin Level in Cerebrospinal Fluid than in Serum Is a Feasible Indicator for Diagnosis of Intracranial Infection.

Objective: To explore the value of the difference in procalcitonin (PCT) levels in serum and cerebrospinal fluid (CSF) for diagnosing intracranial infection in post-neurosurgical patients. Methods: Patients who were treated at our hospital after craniotomy from January 2015 to January 2019 were enrolled in this study. Twenty patients eventually diagnosed with intracranial infection were included in a study group and 22 patients with no intracranial infection were included in a control group. A t-test was used to compare the differences between serum and CSF PCT levels of PCT, and the diagnostic value of PCT was evaluated by receiver operating characteristic (ROC) curve analysis. Results: The serum PCT levels in the study and control groups were 0. 10 ± 0. 03 ng/mL and 0. 09 ± 0. 03 ng/mL, respectively, and they were not substantially different between the groups. The CSF PCT level in the study group was substantially higher than that in the control group, with values of 0. 13 ± 0. 03 ng/mL and 0. 07 ± 0. 02 ng/mL, respectively. The CSF/serum PCT ratio in the study group was substantially higher than that in the control group, with values of 1. 31 ± 0. 19 and 0. 79 ± 0. 23, respectively. The areas under the ROC curve for serum PCT, CSF PCT and the CSF/serum PCT ratio were 0. 56, 0. 92, and 0. 95, respectively, resulting in a substantial difference among the three groups. Conclusion: CSF PCT may be a valuable marker for diagnosing intracranial infection in patients after neurosurgery; in particular, the specificity of CSF PCT is higher if the CSF PCT level is higher than the serum PCT level.

L-lactate in cerebrospinal fluid can be used as a biomarker of encephalitis in cattle.

Cerebrospinal fluid (CSF) changes are significant for antemortem diagnoses of some neurological diseases. The aim of this study was to evaluate if the concentration of L-lactate in CSF could be used to differentiate healthy from encephalitic cattle. Cerebrospinal fluid samples from healthy cattle (n = 10) and from those naturally affected by rabies (n = 15), bovine herpesvirus type 5 meningoencephalitis (n = 16), histophilosis (n = 6), or bacterial encephalitis (n = 4), including 1 case of listeriosis, were collected and analyzed. Physical, biochemical (i.e., protein and glucose), and cellular analyses were performed in fresh samples. L-lactate, electrolytes (sodium, potassium, and chloride), calcium, and magnesium concentrations were measured in CSF samples that were kept frozen. L-lactate concentrations were also measured in plasma. Analysis of variance was used for comparison between groups and receiver operating characteristic analysis was performed considering L-lactate in CSF of healthy versus encephalitic cattle. The CSF L-lactate concentration was significantly higher in cattle with bacterial encephalitis than in healthy cattle; however, it did not differ between viral and bacterial encephalitis. The calcium concentrations were lower in cattle with encephalitis. L-lactate concentration in CSF > 3.6 mmol/L can be accepted as a cut-off value to indicate encephalitis. Thus, L-lactate in CSF is important for the diagnosis of encephalitis in cattle. Despite the small number of cases of bacterial encephalitis, it is suggested that L-lactate was not important for the differentiation between viral and bacterial encephalitis. Additional studies with a greater number of observations are necessary to clarify this, specifically in cases of listeriosis.

Les modifications du liquide céphalorachidien (LCR) sont importantes pour le diagnostic antemortem de certaines maladies neurologiques. Le but de cette étude était d'évaluer si la concentration de L-lactate dans le LCR pouvait être utilisée pour différencier les bovins en bonne santé des bovins encéphalitiques. Des échantillons de LCR provenant de bovins en bonne santé (n = 10) et de sujets infectés naturellement par la rage (n = 15), de méningoencéphalite à BoHV-5 (n = 16), l'histophilose (n = 6), ou d'encéphalite bactérienne (n = 4), notamment un cas de listériose ont été collectés et analysés. Des analyses physiques, biochimiques (protéines et glucose), et cellulaires ont été effectuées dans des échantillons frais. Les concentrations de L-lactate, d'électrolytes (Na+, K+, et Cl−), de calcium (Ca), et de magnésium ont été mesurées dans des échantillons de LCR maintenus congelés. Les concentrations de L-lactate ont également été mesurées dans le plasma. Une analyse de variance a été utilisée pour la comparaison entre les groupes et une analyse ROC (Receiver Operating Characteristic) a été réalisée en considérant le L-lactate dans le LCR de bovins en bonne santé par rapport à des bovins encéphalitiques. La concentration de L-lactate dans le LCR était significativement plus élevée chez les bovins présentant une encéphalite bactérienne que chez les bovins en bonne santé. Cependant, elle ne différait pas entre les bovins présentant une encéphalite virale et bactérienne. Les concentrations de Ca étaient plus faibles chez les bovins atteints d'encéphalite. Une concentration de L-lactate dans le LCR > 3,6 mmol/L peut être acceptée comme valeur seuil indiquant une encéphalite. Ainsi, le L-lactate dans le LCR est important pour le diagnostic de l'encéphalite chez les bovins. Malgré le petit nombre de cas d'encéphalite bactérienne inclus, il a été suggéré que la concentration de L-lactate dans le LCR dans la présente étude n'était pas une méthode de diagnostic important dans la différenciation entre l'encéphalite virale et bactérienne chez les bovins. Des études supplémentaires comportant un plus grand nombre d'observations sont nécessaires pour clarifier cet aspect, en particulier dans les cas de listériose.(Traduit par les auteurs).

Neonates With Urinary Tract Infection: Is a Lumbar Puncture Always Indicated?

BACKGROUND: Our objectives were to determine the prevalence of and to identify risk factors for coexisting bacterial meningitis (BM) in neonates with urinary tract infection (UTI). METHODS: A cross-sectional study was conducted at pediatric emergency department of a tertiary teaching hospital from 2001 to 2017. Infants <29 days of age with UTI (≥10,000 colony-forming units/mL of a single pathogen from a catheterized specimen in association with positive urinalysis) were included. Definite BM was defined as growth of a single bacterial pathogen from a cerebrospinal fluid (CSF) sample and probable BM as (1) positive blood culture with CSF pleocytosis and treatment consistent with BM or (2) antibiotic pretreatment before lumbar puncture, CSF pleocytosis and treatment consistent with BM. Univariate testing was used to identify possible risk factors associated with BM. Receiver operating characteristics curves were constructed for the laboratory markers associated with BM. RESULTS: Three hundred seventy-one infants were included. Five [1.3%; 95% confidence interval (CI): 0.6%-3.1%] had BM: 4 definite BM and 1 probable BM. Risk factors detected for BM were classified as not being well-appearing and a procalcitonin value ≥0.35 ng/mL [sensitivity of 100% (95% CI: 56.6%-100%) and negative predictive value of 100% (95% CI: 96.1%-100%)]. CONCLUSIONS: Coexisting BM occurs uncommonly in neonates with UTI. Well-appearing neonates with UTI and procalcitonin value <0.35 ng/mL were at very low risk for BM; avoiding routine lumbar puncture in these patients should be considered.

Bacteriological investigation--significance of time lapse after death.

In cases of sudden unexpected death in infants and children (SUDI), microbiological investigation has been an important part of the autopsy protocol at the University of Oslo for the last 15 years. The purpose of this study was to compare the microbiological findings in samples taken at hospital admittance shortly after death and at autopsy. Blood cultures and cerebrospinal fluid (CSF) were collected both at the hospital and at autopsy; organ samples were additionally collected at autopsy. Hospital samples were collected at a median of 4.5 h (95% confidence interval [CI] 3.25-5) and autopsy samples at a median of 24.25 h (95% CI 22-25.5) after death. The proportion of positive cultures was stable over time; the post mortal time had no influence on bacterial growth. As long as the autopsy is performed within 48 h after death, prior microbiological examination is unnecessary. Blood culture, CSF and lung specimens are the best predictors in our study.