Cerebrospinal Fluid Lactate Research Articles

Cerebrospinal Fluid Lactate Levels as a Prognostic Indicator in Patients With Cryptococcal Meningitis Who Are HIV Negative: A Retrospective Cohort Study.

Cryptococcal meningitis (CM) is a severe central nervous system infection. In patients with HIV infections and coexisting CM, elevated baseline cerebrospinal fluid (CSF) lactate levels can predict increased mortality. However, the CSF lactate level's significance in patients with CM who are HIV negative remains unclear, necessitating further investigation to elucidate the potential distinctions and enhance patient management. This study investigated the significance of CSF lactate levels in patients with CM who were HIV negative. This retrospective study utilized data from the clinical databases of patients who underwent lumbar punctures at a medical center in Kaohsiung City, southern Taiwan. Demographic data, CSF lactate levels, routine CSF analyses, and hematologic and neurologic findings were evaluated. The optimal CSF lactate threshold value was determined by the Youden index. This retrospective study included 70 patients with CM, among whom 44 (63%) and 26 (37%) tested negative and positive for HIV, respectively. The group without HIV exhibited higher CSF lactate levels, with an optimal CSF lactate cutoff point of 7.935 mmol/L for predicting 90-day mortality, resulting in significant predictive accuracies (area under the curve, 0.755; sensitivity, 57.1%; specificity, 100%); this value was an independent mortality predictor in patients who were HIV negative. In patients with CM who were HIV negative, CSF lactate levels ≥7.935 mmol/L correlated with higher mortality rates but without statistical significance. All patients with CM who were HIV negative and had CSF lactate levels ≥7.935 mmol/L died within 3 months of admission. Patients with CM who were HIV negative had elevated CSF lactate levels that correlated with adverse outcomes, enabling early identification of high-risk individuals.

Mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes with coexisting nemaline myopathy: a case report

BackgroundMitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes and nemaline myopathy are two rare genetic conditions. We report the first case reported in world literature with coexistence of both these rare disorders.Case presentationA 11-year-old previously healthy Sri Lankan male child, product of a nonconsanguineous marriage with normal development presented with acute onset short lasting recurring episodes of right-sided eye deviation with impaired consciousness. In between episodes he regained consciousness. Family history revealed a similar presentation in the mother at 36 years of age. Examination was significant for short stature and proximal upper and lower limb weakness. His plasma and cerebrospinal fluid lactate were elevated. Magnetic resonance imaging brain had evidence of an acute infarction in the right occipital territory. Sanger sequencing for common mitochondrial variants of mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes confirmed this diagnosis. Whole exome sequencing revealed pathogenic compound heterozygous variants in NEB gene implicating in coexisting nemaline myopathy. Acute presentation was managed with supportive care, antiepileptics, and mitochondrial supplementation. Currently he is stable on daily supplementation of arginine and limb-strengthening physiotherapy. He is being monitored closely clinically and with serum lactate level.ConclusionGenetic diseases are rare. Coexistence of two genetic conditions is even rarer. Genetic confirmation of diagnosis is imperative for prediction of complications, accurate management, and genetic counseling.

Frequency of a Positive Cerebrospinal Fluid Study in Patients Presenting With Febrile Seizures

Background: Febrile seizures are a common neurological condition in pediatric practice, affecting 2-5% of children globally. These seizures occur in the context of fever without evidence of central nervous system infection or metabolic disturbance. While often benign, febrile seizures are associated with significant morbidity and can cause considerable distress for both patients and caregivers. The role of cerebrospinal fluid (CSF) abnormalities in the pathogenesis of febrile seizures is not well understood, but identifying these factors may help predict the risk of seizure occurrence. Objective: To determine the frequency of positive cerebrospinal fluid abnormalities in pediatric patients with febrile seizures and to assess the impact of these abnormalities on the risk of febrile seizures. Methods: This prospective cohort study was conducted from January 2022 to December 2023 at the Department of Paediatrics, Combined Military Hospital, Rawalpindi. A total of 117 pediatric patients aged 1 to 12 years with a history of febrile seizures presenting with a febrile illness were included. Patients with prior febrile seizures, metabolic/electrolyte disorders, or signs of meningeal infection were excluded. Comprehensive data collection included demographic information, clinical history, and CSF analysis for cell count, total protein, glucose, lactate, and electrolyte levels. Patients were monitored for febrile seizure occurrence during hospitalization. Data were analyzed using SPSS version 25, with continuous variables expressed as medians and interquartile ranges (IQR) and categorical variables as frequencies and percentages. Odds ratios (ORs) with 95% confidence intervals (CIs) were calculated to assess the association between CSF abnormalities and febrile seizures. Results: The median age of the patients was 3.0 years (IQR: 2.0), with 57.3% (n=67) being male. Febrile seizures occurred in 22.2% (n=26) of patients during hospitalization. Elevated CSF total protein (>60 mg/dL) was observed in 28.2% of patients, CSF glucose (>42 mg/dL) in 12.0%, CSF lactate (>2.0 mmol/L) in 13.7%, and CSF calcium (>1.25 mmol/L) in 10.3%. These abnormalities were significantly associated with an increased risk of febrile seizures: CSF total protein (OR: 3.55, 95% CI: 1.42–8.86, p=0.005), CSF glucose (OR: 13.59, 95% CI: 3.79–48.71, p<0.001), CSF lactate (OR: 4.61, 95% CI: 1.53–13.92, p=0.004), and CSF calcium (OR: 15.52, 95% CI: 3.81–63.36, p<0.001). Conclusion: This study identified significant associations between elevated CSF total protein, glucose, lactate, and calcium levels and an increased risk of febrile seizures in pediatric patients. CSF analysis could be a valuable tool in identifying children at higher risk for febrile seizures, potentially guiding preventive strategies and clinical management.

Lactate dehydrogenase-1 may play a key role in the brain energy disturbance caused by cryptococcal meningitis

BackgroundCryptococcal meningitis (CM) may affect the conversion of lactate to pyruvate in the brain, resulting in abnormal levels of adenosine triphosphate (ATP) throughout the brain. Lactate conversion to pyruvate is mainly caused by lactic dehydrogenase 1 (LDH1), which is composed of four LDHB subunits. However, the underlying mechanism of LDH1 in CM remains unclear. MethodsCerebrospinal fluid (CSF) from 17 patients was collected, including eight patients with non-infectious diseases of the central nervous system and nine patients with CM. Based on clinical data and laboratory reports, data regarding intracranial pressure, CSF white cell counts, lactate dehydrogenase (LDH), adenosine deaminase, glucose, protein, and chloridion were collected. Meanwhile, LDH1, LDH5, lactate, pyruvate, and ATP levels were detected in CSF. Whereafter, the levels of lactate, pyruvate, ATP, and the amplitude and frequency of action potentials in the neurons with low expression of LDHB were explored. ResultsIntracranial pressure and white cell count in CSF were significantly increased in patients with CM. In patients with CM, the LDH1, pyruvate, and ATP levels in the CSF were significantly decreased, and the levels of lactate were found to be increased. Furthermore, pyruvate and ATP levels were decreased, while lactate was increased in the neurons with low expression of LDHB. The amplitude and frequency of APs in the neurons with low expression of LDHB were significantly decreased. ConclusionReduced levels of LDH1 in the brain of patients with CM may lead to increased lactate levels, decreased pyruvate and ATP levels, and negatively affect neuronal activity.

Glioma grade and post-neurosurgical meningitis risk

BackgroundPost-neurosurgical meningitis (PNM) constitutes a grave complication associated with substantial morbidity and mortality. This study aimed to determine the risk factors predisposing patients to PNM following surgery for low- and high-grade gliomas.MethodsWe conducted a retrospective analysis encompassing all patients who underwent glioma surgery involving craniotomy at Turku University Hospital, Turku, Finland, between 2011 and 2018. Inclusion criteria for PNM were defined as follows: (1) Positive cerebrospinal fluid (CSF) culture, (2) CSF leukocyte count ≥ 250 × 106/L with granulocyte percentage ≥ 50%, or (3) CSF lactate concentration ≥ 4 mmol/L, detected after glioma surgery. Glioma grades 3–4 were classified as high-grade (n = 261), while grades 1–2 were designated as low-grade (n = 84).ResultsAmong the 345 patients included in this study, PNM developed in 7% (n = 25) of cases. The median time interval between glioma surgery and diagnosis of PNM was 12 days. Positive CSF cultures were observed in 7 (28%) PNM cases, with identified pathogens encompassing Staphylococcus epidermidis (3), Staphylococcus aureus (2), Enterobacter cloacae (1), and Pseudomonas aeruginosa (1). The PNM group exhibited a higher incidence of reoperations (52% vs. 18%, p < 0.001) and revision surgery (40% vs. 6%, p < 0.001) in comparison to patients without PNM. Multivariable analysis revealed that reoperation (OR 2.63, 95% CI 1.04–6.67) and revision surgery (OR 7.08, 95% CI 2.55–19.70) were significantly associated with PNM, while glioma grade (high-grade vs. low-grade glioma, OR 0.81, 95% CI 0.30–2.22) showed no significant association.ConclusionsThe PNM rate following glioma surgery was 7%. Patients requiring reoperation and revision surgery were at elevated risk for PNM. Glioma grade did not exhibit a direct link with PNM; however, the presence of low-grade gliomas may indirectly heighten the PNM risk through an increased likelihood of future reoperations. These findings underscore the importance of meticulous post-operative care and infection prevention measures in glioma surgeries.

Diagnostic Value of Serum Procalcitonin, CSF Neutrophil-to-lymphocyte Ratio, and CSF Lactate in Pediatric Bacterial Meningoencephalitis.

Bacterial meningoencephalitis presents significant diagnostic and therapeutic challenges with high morbidity and mortality in pediatric populations worldwide. The early and precise identification of the etiology of these infections is essential for effective treatment and better patient results. Traditional diagnostic methods, while effective, can be time-consuming. This manuscript aims to evaluate the accuracy of serum procalcitonin (PCT), cerebrospinal fluid (CSF) neutrophil-to-lymphocyte ratio (NLR), and CSF lactate as biomarkers in pediatric bacterial meningoencephalitis. From March 2021 to November 2023, a cross-sectional study was conducted at Dr. Sardjito General Hospital, a tertiary referral hospital in Yogyakarta, Indonesia. One hundred ninety-seven patients underwent complete clinical and laboratory examinations before being divided into bacterial and non-bacterial groups based on CSF culture results and cytochemical profiles. The diagnostic accuracy was evaluated by the receiver operating characteristic curve using Statistical Package for the Social Sciences. Serum PCT, CSF NLR, and CSF lactate levels showed a notable increase in the bacterial meningoencephalitis group (mean = 4.63 ± 5.52 ng/ml, 4.39 ± 6.68, and 3.59 ± 2.38 mmol/l, respectively) compared to the viral/aseptic group (mean = 0.51 ± 0.88 ng/ml, 0.33 ± 0.95, and 2.25 ± 2.33 mmol/l, respectively) ( P < 0.001). Serum PCT and CSF NLR combined measurement had high sensitivity (86.4%) and specificity (88.6%), with an area under the curve of 0.929 (95% confidence interval, 0.873-0.985), surpassing other tested biomarkers. The findings suggest that combining serum PCT and CSF NLR could be beneficial for early diagnosis, potentially allowing timely, targeted treatment and differentiating between bacterial and non-bacterial infections, ultimately improving patient outcomes.

Astrocytic LRP1 enables mitochondria transfer to neurons and mitigates brain ischemic stroke by suppressing ARF1 lactylation

Low-density lipoprotein receptor-related protein-1 (LRP1) is an endocytic/signaling cell-surface receptor that regulates diverse cellular functions, including cell survival, differentiation, and proliferation. LRP1 has been previously implicated in the pathogenesis of neurodegenerative disorders, but there are inconsistencies in its functions. Therefore, whether and how LRP1 maintains brain homeostasis remains to be clarified. Here, we report that astrocytic LRP1 promotes astrocyte-to-neuron mitochondria transfer by reducing lactate production and ADP-ribosylation factor 1 (ARF1) lactylation. In astrocytes, LRP1 suppressed glucose uptake, glycolysis, and lactate production, leading to reduced lactylation of ARF1. Suppression of astrocytic LRP1 reduced mitochondria transfer into damaged neurons and worsened ischemia-reperfusion injury in a mouse model of ischemic stroke. Furthermore, we examined lactate levels in human patients with stroke. Cerebrospinal fluid (CSF) lactate was elevated in stroke patients and inversely correlated with astrocytic mitochondria. These findings reveal a protective role of LRP1 in brain ischemic stroke by enabling mitochondria-mediated astrocyte-neuron crosstalk.

Corrigendum: Psychosocial stress moderates the relationship between cerebrospinal fluid lactate dehydrogenase and the duration of untreated psychosis in first-episode psychosis

Corrigendum: Psychosocial stress moderates the relationship between cerebrospinal fluid lactate dehydrogenase and the duration of untreated psychosis in first-episode psychosis

Validation of a rapid technique of blood gas analysis for cerebrospinal fluid (CSF) lactate and glucose

Validation of a rapid technique of blood gas analysis for cerebrospinal fluid (CSF) lactate and glucose

The agreement between jugular bulb and cerebrospinal fluid lactate levels in patients with out-of-hospital cardiac arrest

We investigated the agreement between the jugular bulb (JB) and cerebrospinal fluid (CSF) lactate levels. The study was conducted from July 2021 to June 2023 as a prospective observational cohort study at a single center. The right jugular vein was accessed, and the placement of JB catheter tip was confirmed using lateral cervical spine X-ray. A lumbar catheter was inserted between the 3rd and 4th lumbar spine of the patient. Lactate levels were measured immediately, 24 h, 48 h, and 72 h after ROSC. In patients with a good neurological prognosis, kappa between JB and CSF lactate levels measured immediately, at 24 h, 48 h, and 72 h after ROSC were 0.08, 0.36, 0.14, − 0.05 (p = 0.65, 0.06, 0.48, and 0.75, respectively). However, in patients with a poor neurological prognosis, kappa between JB and CSF lactate levels measured immediately, at 24 h, 48 h, and 72 h after ROSC were 0.38, 0.21, 0.22, 0.12 (p = 0.001, 0.04, 0.04, and 0.27, respectively). This study demonstrated that JB lactate levels exhibited significant agreement with arterial lactate levels, compared to CSF lactate levels. Therefore, this should be considered when using JB lactate to monitor cerebral metabolism.

The diagnostic performance of GeneXpert MTB/RIF in tuberculosis meningitis: A multicentre accuracy study

To evaluate the performance of GeneXpert MTB/RIF (Xpert) for tuberculous meningitis (TBM) and to identify additional indicators to improve diagnostic accuracy. An accuracy study was conducted. During 2011-2019, 243 TBM with 140 non-TBM in three TB-designated facilities in China were enrolled. Microbiological evidence of M tuberculosis (Mtb) in CSF was used as the reference. Additional indicators were identified by Boosted-Classification and Regression Tree (CART), the improvement of diagnostic performance was evaluated by ROC. The diagnostic sensitivity of Xpert was 71.1 % for definite TBM, and 5.5 % for probable/possible TBM. The positive rate of Xpert was improved with cerebrospinal fluid (CSF) increasing volume and was associated with CSF color (yellow). The additional indicators obtained by CART were CSF lactate and glucose and increased the sensitivity to 96.1 % (definite TBM) and 84.6 % (probable/possible TBM). The diagnostic performance of Xpert was satisfactory in definite TBM and would significantly be improved by the additional use of CSF lactate and glucose.

Clinical, Neuroimaging, and Metabolic Footprint of the Neurodevelopmental Disorder Caused by Monoallelic HK1 Variants.

Hexokinase 1 (encoded by HK1) catalyzes the first step of glycolysis, the adenosine triphosphate-dependent phosphorylation of glucose to glucose-6-phosphate. Monoallelic HK1 variants causing a neurodevelopmental disorder (NDD) have been reported in 12 individuals. We investigated clinical phenotypes, brain MRIs, and the CSF of 15 previously unpublished individuals with monoallelic HK1 variants and an NDD phenotype. All individuals had recurrent variants likely causing gain-of-function, representing mutational hot spots. Eight individuals (c.1370C>T) had a developmental and epileptic encephalopathy with infantile onset and virtually no development. Of the other 7 individuals (n = 6: c.1334C>T; n = 1: c.1240G>A), 3 adults showed a biphasic course of disease with a mild static encephalopathy since early childhood and an unanticipated progressive deterioration with, e.g., movement disorder, psychiatric disease, and stroke-like episodes, epilepsy, starting in adulthood. Individuals who clinically presented in the first months of life had (near)-normal initial neuroimaging and severe cerebral atrophy during follow-up. In older children and adults, we noted progressive involvement of basal ganglia including Leigh-like MRI patterns and cerebellar atrophy, with remarkable intraindividual variability. The CSF glucose and the CSF/blood glucose ratio were below the 5th percentile of normal in almost all CSF samples, while blood glucose was unremarkable. This biomarker profile resembles glucose transporter type 1 deficiency syndrome; however, in HK1-related NDD, CSF lactate was significantly increased in all patients resulting in a substantially different biomarker profile. Genotype-phenotype correlations appear to exist for HK1 variants and can aid in counseling. A CSF biomarker profile with low glucose, low CSF/blood glucose, and high CSF lactate may point toward monoallelic HK1 variants causing an NDD. This can help in variant interpretation and may aid in understanding the pathomechanism. We hypothesize that progressive intoxication and/or ongoing energy deficiency lead to the clinical phenotypes and progressive neuroimaging findings.

Measurement of cerebrospinal fluid lactate levels in pediatric patients with suspected ventriculoperitoneal shunt infection: A retrospective cohort study

IntroductionVentriculoperitoneal shunt (VPS) infection is a severe complication. Early diagnosis could help to decrease morbidity and treatment costs. Lactate has been used for the diagnosis of other central nervous system infections. The aim of this study is to determine the usefulness of lactate for the diagnosis of VPS infection. MethodologyRetrospective cohort study. Lactate was measured in patients who consulted with VPS dysfunction between May 2019 and May 2022. Mean were compared according to culture results. A Receiver Operating Characteristic (ROC) curve was performed to determine the appropriate cut-off point. ResultLactate has a high negative predictive value but a low positive predictive value for the diagnosis of ventriculitis.

Psychosocial stress moderates the relationship between cerebrospinal fluid lactate dehydrogenase and the duration of untreated psychosis in first-episode psychosis.

Previous research has shown that lower lactate dehydrogenase (LDH) concentrations in cerebrospinal fluid (CSF) are associated with longer prodromal symptoms in first-episode psychosis (FEP). We aimed to study whether there is a relationship between the duration of untreated psychosis (DUP) and LDH and other CSF biomarkers in FEP and whether stressful life events moderate this association. Ninety-five inpatients with FEP and with less than 6 weeks of antipsychotic treatment were included in the study. All participants were informed about the nature of the study, which was approved by the local ethics committee, and signed an informed consent form. A lumbar puncture was performed at index admission (baseline) to measure CSF parameters (glucose, total protein, LDH). The DUP was assessed with the Quick Psychosis Onset and Prodromal Symptoms Inventory (Q-POPSI). Stressful life events (SLEs) in the previous 6 months were assessed with the List of Threatening Experiences. We dichotomized the SLE variable into having experienced at least one SLE or no experience of SLEs. Statistical analyses were performed with SPSS v. 25.0. Total protein and LDH concentrations were natural log transformed (ln) to reduce skewness. Multiple linear regression analyses were conducted to explore the association between the DUP and CSF parameters (considered the dependent variable). Age, sex, DUP and SLEs were considered independent variables. We tested the DUP by SLE interaction. Significant interactions were included in the final model. The threshold for significance was set at p<0.05. Fifty-four FEP patients (56.8%) reported an SLE in the previous 6 months. There were no significant differences in the DUP between patients with or without SLEs. There were no significant differences in CSF biomarkers between the SLE groups. In the multiple linear regression analyses, we found a significant DUP by SLE interaction effect on CSF LDH concentrations (standardized beta= -0.320, t= -2.084, p= 0.040). In patients with SLEs, a shorter DUP was associated with higher CSF LDH concentrations and vice versa. No significant associations were found between the DUP or SLEs and other CSF biomarkers (glucose, total proteins). Our study suggests that psychosocial stress moderates the relationship between the onset of psychosis and CSF biomarkers related to bioenergetic systems.

Reliability of a point of care testing blood gas analyzer for measurement of lactate levels in cerebrospinal fluid

Analysis of cerebrospinal fluid (CSF), including lactate, is key for diagnosis of acute meningitis. Since blood gas analyzers (BGA) enable rapid and safe blood-lactate measurements, we evaluated the reliability of RAPIDPoint 500 BGA to provide a fast and accurate measure of CSF lactate. In this study, CSF lactate levels were measured by a reference assay and on RAPIDPoint 500 BGA. Comparability was evaluated through difference analysis, using Bland Altman test, and linear regression analysis, using the Passing Bablok test. Agreement rate according to CSF lactate (≥3.5 and <3.5 mmol/L) was calculated using kappa (κ) statistic. Population study included 98 CSF samples. Concerning difference analysis, according to Bland-Altman test, bias was 0.13 mmol/L (CI 95%: −0.26 to 0.52 mmol/L. In regression analysis, according to Passing-Bablok equation a systematic difference between both assays was found. In concordance analysis, the interrate realibility was very high (κ: 0.964). According to our resuls, although a systematic difference was detected when lactate levels were measured on RAPIDPoint 500 BGA, the results from Bland-Altman test and the high agreement rate support that this POCT analyzer could be useful for a early and safe detection of patients with high probability of increased CSF lactate level.

Clinical characteristics of 13 cases of Coronavirus infection complicated with severe central nervous system lesions in Shanxi children’s hospital

BackgroundThe new coronavirus Omicron variant strain spread rapidly worldwide and is currently the primary mutant strain prevalent in the world.ObjectiveTo explore the clinical features of severe central nervous system lesions in children infected with novel coronavirus Omicron mutant strain, so as to provide a reference for clinical diagnosis and treatment.Materials and methodsThe clinical data of 13 children diagnosed with novel coronavirus Omicron variant strain complicated with severe central nervous system infection from December 13, 2022, to January 31, 2023, in the Children’s Intensive Care Medicine Department of Shanxi Children’s Hospital were retrospectively analyzed.ResultsAmong the 13 children, there were 9 males (69%) and 4 females (31%); the ages ranged from 1-year-old 16 days to 13 years old, with a median age of 9 years old, and most of them were school-age children (84.6%). The 13 children were usually healthy, but this time they were all positive for the new coronavirus nucleic acid test. The 13 children had obvious signs of the abnormal nervous system when they were admitted to the hospital, among which 12 cases (92.3%) showed convulsions, 11 children had obvious disturbance of consciousness (84.6%) when they were admitted to the hospital, and 5 children had circulatory disorders (38.4%). Among the 13 children, 2 were cured (15.3%), 5 children had serious sequelae (38.4%) when they were discharged from the hospital, and 6 children died of severe illness (46.3%).ConclusionThis study illuminates the clinical characteristics of severe central nervous system complications in children with coronavirus variant infection, highlighting rapid onset, swift progression, relatively poor prognosis, and notable symptoms such as high fever, convulsions, altered consciousness, elevated interleukin-6 levels, increased cerebrospinal fluid lactate levels, and early imaging changes.

Comparison of CSF Lactate and Serum Procalcitonin in Diagnosing Pyogenic Meningitis

Background: Meningitis, a potentially life-threatening inflammation of the meninges, poses diagnostic challenges, particularly in differentiating bacterial meningitis (BM) from other forms. The identification of effective biomarkers is crucial for accurate diagnosis and treatment. Objective: This study aimed to evaluate the diagnostic utility of cerebrospinal fluid (CSF) lactate levels and serum procalcitonin (PCT) in distinguishing BM from tuberculous and viral meningitis. Methods: Conducted at the Neurology Department of Pak Emirates Military Hospital from February to May 2023, this observational study included 55 patients, with a mean age of 44.03 years. Patients were selected based on clinical signs and symptoms of meningitis, with those having received prior antibiotic treatment excluded. CSF and serum PCT levels were measured, and statistical analyses were performed to compare these biomarkers across different meningitis etiologies. Results: Of the 55 patients, 30 (54.50%) were diagnosed with BM, 15 (27.30%) with viral meningitis, and 10 (18.20%) with tuberculous meningitis. The mean CSF lactate level in BM patients was 9.36 ± 7.95 mmol/L, significantly higher than in non-bacterial cases. Similarly, serum PCT levels were markedly elevated in BM patients (24.05 ng/ml ± 39.82 ng/ml). The study found a strong correlation between elevated CSF lactate and serum PCT levels with the diagnosis of BM (P &lt; 0.05). Conclusion: CSF lactate levels and serum PCT are reliable biomarkers for diagnosing BM. Their elevated levels in BM patients compared to those with tuberculous or viral meningitis can assist in accurate and timely diagnosis, contributing to improved patient outcomes and effective antibiotic stewardship.

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

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 β-2 transferrin (β-2TF) and transferrin (TF) in the cerebrospinal fluid (CSF) for the identification of intracranial infection after neurosurgery. 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), β-2TF, and TF levels in the CSF. CSF LA levels were significantly higher in the PNM, PNBM, and PNAM groups compared with the non-PNM group ( P < .05). The CSF β-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, β-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, β-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, β-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, β-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 β-2TF were independent risk factors for intracranial infection. Postoperative cerebral infections can be identified using CSF β-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 β-2TF were independent risk factors for cerebral infection.

Brain metabolism during delirium

AbstractBackgroundAltered cerebral glucose metabolism manifested by increased cerebrospinal fluid (CSF) lactate and decreased neuron specific enolase during delirium has been found in CSF analyses in multiple settings, although without change in CSF or blood glucose. These changes correlate with markers of delirium severity and outcomes of delirium.However, patients with delirium are acutely unwell in hospital and have multiple comorbidities. The contribution of acute illness and dementia have not been excluded.MethodWe studied two groups of acutely unwell older people in hospital after excluding underlying dementia by history and the Informant Questionnaire on Cognitive Decline in the Elderly. The first group had delirium and the second group had no delirium. All patients underwent a 18F‐fluorodeoxyglucose positron emission tomography (FDG‐PET) scan in hospital while unwell, and during delirium for the first group. Confounders on FDG‐PET such as structural brain lesions and medications that affect brain metabolism were excluded.Then we also compared the delirium FDG‐PET scans to a group with Alzheimer’s dementia.ResultPatients with delirium demonstrated a unique, novel pattern of brain hypometabolism that reflected symptoms of delirium. The affected areas included: bilateral thalami; right posterior cingulate cortex (PCC); right superior frontal, right infero‐lateral anterior temporal and left superior parietal cortices. The areas highly negatively correlated with delirium severity scores (Spearman’s rank correlation coefficients between ρ = ‐0.39 and ‐0.71; p values from 0.089 to 0.001) and performance on a range of relevant neuropsychological tests, for example thalami and Trail Making Test B (Spearman’s ρ = ‐0.52; p = 0.028). Direct comparison to AD scans significant thalamic hypometabolism (p&lt;0.01) in delirium, but the PCC was not different.ConclusionIn patients with acute illness but without dementia, delirium is accompanied by regional cerebral hypometabolism in a distribution that is not consistent with any known pattern of dementia. While there is some overlap with AD, thalamic hypometabolism is atypical of AD and consistent with the clinical features of delirium.ReferencesNitchingham AR, Pereira JV‐B, Wegner EA, Oxenham V, Close J Caplan GA. Regional cerebral hypometabolism on 18F‐FDG PET/CT scan in delirium is independent of acute illness and dementia. Alzheimers &amp; Dementia 2022; 1‐10.

Where to Draw Cerebrospinal Fluid from an External Ventricular Drain? Comparison of Cerebrospinal Fluid Parameters between Two Different Collection Sites

Background: High cerebrospinal fluid (CSF) sampling frequency is considered a risk factor for external ventricular drain (EVD)-associated infections. To reduce manipulation at the proximal port and potentially minimize the risk of an infection, we aimed to analyze whether CSF parameters sampled from the far distal collection bag could provide reliable results compared to the proximal port. Methods: We included patients who were treated with an EVD at our neurosurgical intensive care unit (ICU) between June 2021 and September 2022. CSF sampling, including microbiological analysis, was performed simultaneously from the proximal port and the collection bag. Spearman’s correlation coefficients were calculated to assess the correlation of CSF cell count, protein, lactate and glucose between the two sample sites. Results: We analyzed 290 pairs of CSF samples in 77 patients. Ventriculitis was identified in 4/77 (5%) patients. In 3/4 patients, microbiological analysis showed the same bacterial species at both sample sites at the same time. Spearman’s correlation coefficient showed that CSF cell count (r = 0.762), lactate (r = 0.836) and protein (r = 0.724) had a high positive correlation between the two collection sites, while CSF glucose (r = 0.663) showed a moderate positive correlation. Conclusion: This study shows that biochemical CSF parameters can be reliably assessed from the EVD collection bag.