Neuron-specific enolase levels and neuroimaging in asphyxiated term newborns

Association between cerebrospinal fluid levels of neuro-specific enolase after hypothermia alone and in combination with neurodevelopmental outcomes at age six years

BACKGROUND

Hypoxic-ischemic encephalopathy (HIE) is still associated with death and sequelae including cerebral palsy and intellectual disability despite induced hypothermia. Biomarkers, as early predictive indicators of adverse outcomes, are lacking.

AIMS

To investigate whether post-rewarming cerebrospinal fluid (CSF)-neuro-specific enolase (NSE) levels after hypothermia are associated with neurodevelopmental outcomes at age six years, alone or when combined with amplitude-integrated electroencephalography (aEEG) and brain magnetic resonance imaging (MRI), as neuroimaging and neurophysiological indicators, respectively.

PARTICIPANTS

We retrospectively enrolled 157 patients with HIE from 2011 to 2018 with available post-rewarming CSF-NSE levels and developmental tests at age six years. Of these, 148 met the inclusion criteria, and 87 were evaluated in the final analysis.

OUTCOME MEASURES

Multivariate receiver operating characteristic analysis determined the predictive ability of post-rewarming CSF-NSE levels for adverse outcomes including death and cerebral palsy, intellectual disability, and borderline disability at age 6 years either singly or in combination with aEEG and MRI findings, using logistic regression analysis.

RESULTS

The cut-off value for CSF-NSE at a median 5 days after birth was 233 ng/dL (area under the curve 0.97, 95 % confidence intervals of 0.93-1.00, sensitivity 1, specificity 0.94) for death. Regarding cerebral palsy and intellectual disability, the combination of abnormal aEEG at 72 h, moderate-severe MRI injury findings, and with or without CSF-NSE (cut-off value: 55 ng/mL), odds ratio (95 % confidence intervals) improving from 8.6 (2.7-27.8) to 12.4 (3.5-43.9) (p < 0.01).

CONCLUSIONS

In patients with HIE, post-rewarming CSF-NSE levels were associated not only with death independently but with cerebral palsy and intellectual disability in combination with EEG and MRI findings.

Biomarkers of hypoxic-ischemic encephalopathy: a systematic review

BACKGROUND

Current diagnostic criteria for hypoxic-ischemic encephalopathy in the early hours lack objective measurement tools. Therefore, this systematic review aims to identify putative molecules that can be used in diagnosis in daily clinical practice (PROSPERO ID: CRD42021272610).

DATA SOURCES

Searches were performed in PubMed, Web of Science, and Science Direct databases until November 2020. English original papers analyzing samples from newborns > 36 weeks that met at least two American College of Obstetricians and Gynecologists diagnostic criteria and/or imaging evidence of cerebral damage were included. Bias was assessed by the Newcastle-Ottawa Scale. The search and data extraction were verified by two authors separately.

RESULTS

From 373 papers, 30 met the inclusion criteria. Data from samples collected in the first 72 hours were extracted, and increased serum levels of neuron-specific enolase and S100-calcium-binding protein-B were associated with a worse prognosis in newborns that suffered an episode of perinatal asphyxia. In addition, the levels of glial fibrillary acidic protein, ubiquitin carboxyl terminal hydrolase isozyme-L1, glutamic pyruvic transaminase-2, lactate, and glucose were elevated in newborns diagnosed with hypoxic-ischemic encephalopathy. Moreover, pathway analysis revealed insulin-like growth factor signaling and alanine, aspartate and glutamate metabolism to be involved in the early molecular response to insult.

CONCLUSIONS

Neuron-specific enolase and S100-calcium-binding protein-B are potential biomarkers, since they are correlated with an unfavorable outcome of hypoxic-ischemic encephalopathy newborns. However, more studies are required to determine the sensitivity and specificity of this approach to be validated for clinical practice.

Serum neuron-specific enolase, magnetic resonance imaging, and electrophysiology for predicting neurodevelopmental outcomes of neonates with hypoxic-ischemic encephalopathy: a prospective study

Background

Neonatal hypoxic-ischemic encephalopathy (HIE) is an important cause of mortality and morbidity. Effective indicators for the early diagnosis of brain injury after HIE and prognosis are lacking. This study aimed to examine the predictive value of serum neuron-specific enolase (NSE), amplitude-integrated electroencephalography (aEEG), and magnetic resonance imaging (MRI), alone and in combination, for the neurological outcomes in neonates with HIE.

Methods

Newborns with HIE born and treated at the Third Affiliated Hospital of An-Hui Medical University were consecutively included in this prospective cohort study (June 2013 to December 2020). Encephalopathy was classified as mild, moderate or severe according to Samat and Sarnat. All patients were assessed serum 1-day NSE and 3-day NSE levels after birth. The children were classified by neurological examination and Bayley Scales of Infant Development II at 18 months of age. ROC analysis was used to evaluate the predictive accuracy of the neurodevelopment outcomes.

Results

A total of 50 HIE neonates were enrolled (normal group: 32 (64.0%), moderate delay: 5 (10.0%), severe delay: 30(26.0%)) according to Bayley II scores. Serum 3-day NSE levels increased with worsening neurodevelopment outcomes (normal: 20.52 ± 6.42 μg/L vs. moderate: 39.82 ± 5.92 μg/L vs. severe: 44.60 ± 9.01 μg/L, P < 0.001). The MRI findings at 4–7 days after birth were significantly different among the three groups (P < 0.001). Forty-two (84.0%) children had abnormal aEEG. The combination of the three abnormalities combined together had 100% sensitivity, 97.70% specificity, 98.25% PPV, and 99.98% NPV.

Conclusions

MRI, aEEG, and 3-day NSE can predict the neurological prognosis of newborns with HIE without hypothermia treatment. Their combination can improve the predictive ability for long-term neurobehavioral prognosis.

Promising candidate cerebrospinal fluid biomarkers of seizure disorder, infection, inflammation, tumor, and traumatic brain injury in pediatric patients

Cerebrospinal fluid (CSF) is a dynamic metabolically active body fluid that has many important roles and is commonly analyzed in pediatric patients, mainly to diagnose central nervous system infection and inflammation disorders. CSF components have been extensively evaluated as biomarkers of neurological disorders in adult patients. Circulating microRNAs in CSF are a promising class of biomarkers for various neurological diseases. Due to the complexity of pediatric neurological disorders and difficulty in acquiring CSF samples from pediatric patients, there are challenges in developing CSF biomarkers of pediatric neurological disorders. This review aimed to provide an overview of novel CSF biomarkers of seizure disorders, infection, inflammation, tumor, traumatic brain injuries, intraventricular hemorrhage, and congenital hydrocephalus exclusively observed in pediatric patients.

Value of brain damage biomarkers in cerebrospinal fluid in neonates with hypoxic-ischemic brain injury

Hypoxic-ischemic encephalopathy is one of the leading causes of death and neurological disability worldwide. A key issue in neonates with hypoxic-ischemic encephalopathy is accurately establishing the occurrence and severity of brain lesions soon after a perinatal hypoxic-ischemic event. This is crucial to help with prognosis; guide clinical decision-making, including the use of other therapies; and improve family counseling. Neurobiochemical markers may offer a quantitative approximation for estimating the severity of brain damage and identifying infants who have a high risk of further neurological disability. In addition, they should help identify those neonates who would benefit most from the implementation of other neuroprotective and neuroreparative interventions. Despite considerable progress in this area, relatively few studies have been aimed at examining the clinical utility of brain-specific proteins in cerebrospinal fluid, an important opening to characterizing pathological phenomena associated with hypoxic-ischemic brain injury.

Can we delineate brain injury in full-term neonates using serum biomarkers?

OBJECTIVE: Early identification of neonates at risk of neurological impairment is particularly important for the bedside clinician. Clinical value of S100b and neuron-specific enolase in neonates has not been yet established. We investigated their kinetics and possible early clinical utility in neonatal encephalopathy (NE).STUDY DESIGN: 36 full-term neonates (13 with moderate/severe encephalopathy, 11 with mild encephalopathy, 12 controls) were enrolled and studied prospectively. Serum S100b and neuron-specific enolase (NSE) were measured serially on days(d) 1, 3, 9 and 18 of life. Brain MRI and long-term neurodevelopmental outcome were also assessed.RESULT: Neonates with moderate/severe encephalopathy had significantly increased S100b (d1) and NSE levels (d1, d3, d9) compared to controls. Neuron-specific enolase significantly correlated with the degree of encephalopathy, and a cutoff of 38.8 μg/l (d1) accurately predicted moderate/severe encephalopathy. S100b (d1) cutoff points of 1.6 μg/l and 11.4 μg/l prognosticated severe encephalopathy and death/cerebral palsy, respectively. Both biomarkers correlated well with neuroimaging and Bayley-III scores.CONCLUSION: Combined clinical, laboratory, imaging and neurodevelopmental data indicate that serum S100b and NSE can be useful biomarkers for the diagnosis and prognosis of neonatal brain injury, providing useful information to the bedside clinician.

Cerebrospinal fluid levels of neuron-specific enolase predict the severity of brain damage in newborns with neonatal hypoxic-ischemic encephalopathy treated with hypothermia

Objectives

To investigate whether cerebrospinal fluid levels of neuron-specific enolase (CSF-NSE) during the first 72 hours correlate with other tools used to assess ongoing brain damage, including clinical grading of hypoxic-ischemic encephalopathy (HIE), abnormal patterns in amplitude integrated electroencephalography (aEEG), and magnetic resonance imaging (MRI), as well as with the neurodevelopmental outcomes at two years of age.

Material and methods

Prospective observational study performed in two hospitals between 2009 and 2011. Forty-three infants diagnosed with HIE within 6 hours of life were included. HIE was severe in 20 infants, moderate in 12, and mild in 11. Infants with moderate-to-severe HIE received whole-body cooling. Both the HIE cohort and a control group of 59 infants with suspected infection underwent measurement of CSF-NSE concentrations at between 12 and 72 hours after birth. aEEG monitoring was started at admission and brain MRI was performed within the first 2 weeks. Neurodevelopment was assessed at 24 months.

Results

The HIE group showed higher levels of CSF-NSE than the control group: median 70 ng/ml (29; 205) vs 10.6 ng/ml (7.7; 12.9); p <0.001. Median levels of CSF-NSE in infants with severe, moderate, and mild HIE were 220.5 ng/ml (120.5; 368.8), 45.5 ng/ml (26, 75.3), and 26 ng/ml (18, 33), respectively. CSF-NSE levels correlated were significantly higher in infants with seizures, abnormal aEEG, or abnormal MRI, compared to those without abnormalities. Infants with an adverse outcome showed higher CSF-NSE levels than those with normal findings (p<0.001), and the most accurate CSF-NSE cutoff level for predicting adverse outcome in the whole cohort was 108 ng/ml and 50ng/ml in surviving infants.

Conclusions

In the era of hypothermia, CSF-NSE concentrations provides valuable information as a clinical surrogate of the severity of hypoxic-ischemic brain damage, and this information may be predictive of abnormal outcome at two years of age.

Early predictors of perinatal brain damage: the role of neurobiomarkers

The early detection of perinatal brain damage in preterm and term newborns (i.e. intraventricular hemorrhage, periventricular leukomalacia and perinatal asphyxia) still constitute an unsolved issue. To date, despite technological improvement in standard perinatal monitoring procedures, decreasing the incidence of perinatal mortality, the perinatal morbidity pattern has a flat trend. Against this background, the measurement of brain constituents could be particularly useful in the early detection of cases at risk for short-/long-term brain injury. On this scenario, the main European and US international health-care institutions promoted perinatal clinical and experimental neuroprotection research projects aimed at validating and including a panel of biomarkers in the clinical guidelines. Although this is a promising attempt, there are several limitations that do not allow biomarkers to be included in standard monitoring procedures. The main limitations are: (i) the heterogeneity of neurological complications in the perinatal period, (ii) the small cohort sizes, (iii) the lack of multicenter investigations, (iv) the different techniques for neurobiomarkers assessment, (iv) the lack of consensus for the validation of assays in biological fluids such as urine and saliva, and (v), the lack of reference curves according to measurement technique and biological fluid. In the present review we offer an up-to-date overview of the most promising developments in the use of biomarkers in the perinatal period such as calcium binding proteins (S100B protein), vasoactive agents (adrenomedullin), brain biomarkers (activin A, neuron specific enolase, glial fibrillary acidic protein, ubiquitin carboxyl-terminal hydrolase-L1) and oxidative stress markers.

Neuron-Specific Enolase in Cerebrospinal Fluid Predicts Brain Injury After Sudden Unexpected Postnatal Collapse

BACKGROUND

Biomarkers of brain injury with high predictive value in newborns in critical neurological status are increasingly required. Neuron-specific enolase in cerebrospinal fluid has been shown to be highly predictive in newborns with perinatal hypoxic-ischemic encephalopathy, but its utility has not been examined in sudden unexpected postnatal collapse.

PURPOSE

We analyzed whether the levels of neuron-specific enolase in cerebrospinal fluid can be a useful biomarker to estimate the severity of brain injury in neonates after a sudden unexpected postnatal collapse.

METHODS

This is a prospective observational study of near-term infants who were consecutively admitted with sudden unexpected postnatal collapse in two neonatal intensive care units during a nine-year period. Variables were collected and analyzed regarding the perinatal period, clinical course, severity of encephalopathy, amplitude-integrated encephalography, magnetic resonance imaging findings, and outcome. Neuron-specific enolase in cerebrospinal fluid samples were obtained in 18 infants with sudden unexpected postnatal collapse between 12 and 72 hours after the collapse and compared with those of 29 controls.

RESULTS

The levels of neuron-specific enolase in cerebrospinal fluid were higher in patients than in controls (P < 0.001). Levels of neuron-specific enolase in cerebrospinal fluid in infants with sudden unexpected postnatal collapse were significantly higher in patients who presented severe encephalopathy, seizures, abnormal amplitude-integrated encephalography background, or brain injury on magnetic resonance imaging. Receiver operator characteristic curve analysis revealed a neuron-specific enolase in cerebrospinal fluid cutoff value of maximum predictive accuracy of 61 ng/mL (area under the curve, 1.0; sensitivity, specificity, positive predictive value, and negative predictive value, 100%) for identifying infants who died or had adverse outcomes.

CONCLUSIONS

Levels of neuron-specific enolase in cerebrospinal fluid obtained between 12 and 72 hours after a sudden unexpected postnatal collapse event seem to be a useful biomarker for identifying newborns with severe brain injury and for predicting outcome.

Biomarkers of brain injury in neonatal encephalopathy treated with hypothermia

OBJECTIVE

To determine if early serum S100B and neuron-specific enolase (NSE) levels are associated with neuroradiographic and clinical evidence of brain injury in newborns with encephalopathy.

STUDY DESIGN

Patients who received therapeutic whole-body hypothermia were prospectively enrolled in this observational study. Serum specimens were collected at 0, 12, 24, and 72 hours of cooling. S100B and NSE levels were measured by enzyme linked immunosorbent assay. Magnetic resonance imaging was performed in surviving infants at 7-10 days of life. Standardized neurologic examination was performed by a child neurologist at 14 days of life. Multiple linear regression analyses were performed to evaluate the association between S100B and NSE levels and unfavorable outcome (death or severe magnetic resonance imaging injury/significant neurologic deficit). Cutoff values were determined by receiver operating curve analysis.

RESULTS

Newborns with moderate to severe encephalopathy were enrolled (n = 75). Median pH at presentation was 6.9 (range, 6.5-7.35), and median Apgar scores of 1 at 1 minute, 3 at 5 minutes, and 5 at 10 minutes. NSE and S100B levels were higher in patients with unfavorable outcomes across all time points. These results remained statistically significant after controlling for covariables, including encephalopathy grade at presentation, Apgar score at 5 minutes of life, initial pH, and clinical seizures.

CONCLUSION

Elevated serum S100B and NSE levels measured during hypothermia were associated with neuroradiographic and clinical evidence of brain injury in encephalopathic newborns. These brain-specific proteins may be useful immediate biomarkers of cerebral injury severity.

Copeptin concentration in cord blood in infants with early-onset sepsis, chorioamnionitis and perinatal asphyxia

Background

Vasopressin is one of the most important physiological stress and shock hormones. Copeptin, a stable vasopressin precursor, is a promising sepsis marker in adults. In contrast, its involvement in neonatal diseases remains unknown. The aim of this study was to establish copeptin concentrations in neonates of different stress states such as sepsis, chorioamnionitis and asphyxia.

Methods

Copeptin cord blood concentration was determined using the BRAHMS kryptor assay. Neonates with early-onset sepsis (EOS, n = 30), chorioamnionitis (n = 33) and asphyxia (n = 25) were compared to a control group of preterm and term (n = 155) neonates.

Results

Median copeptin concentration in cord blood was 36 pmol/l ranging from undetectable to 5498 pmol/l (IQR 7 - 419). Copeptin cord blood concentrations were non-normally distributed and increased with gestational age (p < 0.0001). Neonates born after vaginal compared to cesarean delivery had elevated copeptin levels (p < 0.0001). Copeptin correlated strongly with umbilical artery pH (Spearman's Rho -0.50, p < 0.0001), umbilical artery base excess (Rho -0.67, p < 0.0001) and with lactate at NICU admission (Rho 0.54, p < 0.0001). No difference was found when comparing copeptin cord blood concentrations between neonates with EOS and controls (multivariate p = 0.30). The highest copeptin concentrations were found in neonates with asphyxia (median 993 pmol/l). Receiver-operating-characteristic curve analysis showed that copeptin cord blood concentrations were strongly associated with asphyxia: the area under the curve resulted at 0.91 (95%-CI 0.87-0.96, p < 0.0001). A cut-off of 400 pmol/l had a sensitivity of 92% and a specifity of 82% for asphyxia as defined in this study.

Conclusions

Copeptin concentrations were strongly related to factors associated with perinatal stress such as birth acidosis, asphyxia and vaginal delivery. In contrast, copeptin appears to be unsuitable for the diagnosis of EOS.

Magnetic resonance biomarkers of neuroprotective effects in infants with hypoxic ischemic encephalopathy

Evaluation of infants with hypoxic ischemic encephalopathy by magnetic resonance spectroscopy and imaging is useful to direct clinical care, and may assist the evaluation of candidate neuroprotective therapies. Cerebral metabolites measured by magnetic resonance spectroscopy, and visual analysis of magnetic resonance images during the first 30 days after birth accurately predict later neurological outcome and are valid biomarkers of the key physiological processes underlying brain injury in neonatal hypoxic ischemic encephalopathy. Visual assessment of magnetic resonance images may also be a suitable surrogate outcome in studies of neuroprotective therapies but current magnetic resonance methods are relatively inefficient for use in early phase, first in human infant studies of novel neuroprotective therapies. However, diffusion tensor imaging and analysis of fractional anisotropy with tract-based spatial statistics promises to be a highly efficient biomarker and surrogate outcome for rapid preliminary evaluation of promising therapies for neonatal hypoxic ischemic injury. Standardisation of scanning protocols and data analysis between different scanners is essential.

Dihydrotachysterol intoxication treated with pamidronate: a case report

Introduction

Hypoparathyroidism is a chronic condition which requires a lifelong substitution with vitamin D analogues and careful monitoring. This is especially true for older patients and older compounds as dihydrotachysterol with longer half-life that might lead to long-lasting hypercalcemic episodes.

Case presentation

A 74-year old male patient with postsurgical hypoparathyroidism who has been successfully supplemented with dihydrotachysterol (1.7 ml/day) for over 50 years presented with neuropsychiatric disturbances, constipation, renal insufficiency and polyuria. Laboratory investigation demonstrated serum calcium 3.7 mmol/L, serum creatinine 180 micromol/L, urine calcium excretion 1.1 mmol/mmol of the creatinine, normal 25 OH vitamin D₃ and low parathormone and 1,25 di OH vitamin D₃. Careful history revealed that he has been erroneously taking 2.5 ml of dihydrotachysterol per day for at least 6 to 8 weeks that caused vitamin D intoxication and symptomatic hypercalcemia. He was treated with intravenous saline infusion, prednisolone and 60 mg of intravenous sodium pamidronate. On the fourth day after admission serum calcium dropped rapidly within the reference range. The treatment for hypoparathyroidism had to be reinstituted 10 days after dihydrotachysterol had been discontinued when the patient was switched to shorter acting calcitriol.

Conclusions

Here we reported that the immediate use of pamidronate in addition to classic treatment of dihydrotachysterol intoxication with intravenous saline, diuretics and glucocorticoids is an effective treatment choice that leads to rapid resolution of hypercalcemia.

Systematic review of biomarkers of brain injury in term neonatal encephalopathy

Although neonatal hypoxic-ischemic encephalopathy is a common cause of childhood developmental disability, its timing, duration, and outcomes are poorly defined. Biomarkers serve as surrogates for disease injury, evolution, and outcome, but no tissue biomarker in routine clinical use can help predict outcomes in term newborn encephalopathy. We reviewed biomarkers in human term neonatal encephalopathy, to determine if current biomarkers are strong enough for clinical use as predictors of outcomes. A comprehensive search of databases identified 110 publications that met our inclusion criteria, i.e., (1) newborns at >36 weeks; (2) neonatal encephalopathy as defined by the American College of Obstetrics and Gynecology; (3) the use of a serum, urine, or cerebrospinal fluid biomarker; and (4) reported outcomes beyond age 12 months. Of those 110 publications, 22 reported outcomes beyond age 12 months. In single reports, urine lactate (P < 0.001), first urine S100 (P < 0.0001), cord-blood interleukin-6 (P = 0.02), serum nonprotein-bound iron (P < 0.001), serum CD14 cell NFkappaB activation (P = 0.014), serum interleukin-8 (P = 0.03), and serum ionized calcium (P = 0.001) were potential predictors of death or abnormal outcomes. A meta-analysis identified serum interleukin-1b (P = 0.04, n = 3), serum interleukin-6 (P = 0.04, n = 2), cerebrospinal fluid neuron-specific enolase (P = 0.03, n = 3), and cerebrospinal fluid interleukin-1b (P = 0.003, n = 2) as putative predictors of abnormal outcomes in survivors, when measured before age 96 hours. Several serum, urine, and cerebrospinal fluid biomarkers of term neonatal encephalopathy may provide important information regarding long-term outcomes. None, however, were studied extensively enough to warrant routine clinical use. Validation of these markers, either alone or in combination, is required in the development of viable therapeutic interventions.