Serum Neuron-Specific Enolase as a Biomarker of Neonatal Brain Injury-New Perspectives for the Identification of Preterm Neonates at High Risk for Severe Intraventricular Hemorrhage.

Neonatal brain injury (NBI) is a critical condition for preterm neonates with potential long-term adverse neurodevelopmental outcomes. This prospective longitudinal case-control study aimed at investigating the levels and prognostic value of serum neuron-specific enolase (NSE) during the first 3 days of life in preterm neonates (<34 weeks) that later developed brain injury in the form of either periventricular leukomalacia (PVL) or intraventricular hemorrhage (IVH) during their hospitalization. Participants were recruited from one neonatal intensive care unit, and on the basis of birth weight and gestational age, we matched each case (n = 29) with a neonate who had a normal head ultrasound scan (n = 29). We report that serum NSE levels during the first three days of life do not differ significantly between control and preterm neonates with NBI. Nevertheless, subgroup analysis revealed that neonates with IVH had significantly higher concentrations of serum NSE in comparison to controls and neonates with PVL on the third day of life (p = 0.014 and p = 0.033, respectively). The same pattern on the levels of NSE on the third day of life was also observed between (a) neonates with IVH and all other neonates (PVL and control; p = 0.003), (b) neonates with II-IV degree IVH and all other neonates (p = 0.003), and (c) between control and the five (n = 5) neonates that died from the case group (p = 0.023). We conclude that NSE could be an effective and useful biomarker on the third day of life for the identification of preterm neonates at high risk of developing severe forms of IVH.

Early Neonatal C-Reactive Protein Levels and Periventricular Leukomalacia.

BACKGROUND: Cystic periventricular leukomalacia (cPVL) is a strong indicator of subsequent motor and developmental impairments in premature infants. There is a paucity of publications on biomarkers of cPVL. OBJECTIVES: To determine C-reactive protein (CRP) levels during the first week of life of preterm infants who later developed cPVL and to identify the association between CRP levels with perinatal factors. METHODS: We retrospectively included infants ≤ 32 weeks gestation and/or birth weights ≤ 1500 grams; 17 with a cranial ultrasound diagnosis of cPVL and 54 with normal ultrasounds. Serum CRP levels were measured during days 1-7 (CRP1-7d) of life and subdivided into two timing groups: days 1-3 (CRP1-3d) and days 4-7 (CRP4-7d). RESULTS: The cPVL group had significantly higher mean CRP4-7d levels compared to controls (12.75 ± 21.2 vs. 2.23 ± 3.1, respectively, P = 0.03), while CRP1-3d levels were similar. CRP1-7d levels were significantly correlated with maximal fraction of inspired oxygen during the first 12 hours of life (FiO2-12h, r = 0.51, P < 0.001]. Additional risk factors were not associated with CRP levels. CONCLUSIONS: Our finding of elevated CRP4-7d levels and later development of cPVL supports earlier studies on the involvement of inflammation in the pathogenesis of cPVL. Whether CRP could serve as a biomarker of cPVL and its correlation with outcomes, awaits further trials. Furthermore, the correlation between FiO2-12h and CRP1-7d levels suggest that hypoxia and/or hyperoxia may serve as a trigger in the activation of inflammation during the first days of life of preterm infants.

Clinical significance of detecting serum melatonin and SBDPs in brain injury in preterm infants.

BACKGROUND: To investigate the clinical values of serum melatonin and αII spectrin cleavage products (SBDPs) in assessing the severity of brain injury in preterm infants. METHODS: Sixty-four premature infants in total were selected and classified into the brain injury group (BI, n = 30) and the non-brain injury group (CON, n = 34) according to cranial imaging examination. The serum melatonin and SBDPs were detected by ELISA. All the preterm infants were received NBNA testing at 40 weeks of corrected gestational age. RESULTS: The levels of melatonin and SBDPs in the BI group were significantly higher than the CON group (p < 0.05) and the levels in the infants with severe brain injury were significantly higher than those with mild brain injury (p < 0.05), as well as exhibiting a negative correlation with the NBNA score at 40 weeks of corrected gestational age (p < 0.05). CONCLUSIONS: Detecting melatonin and SBDPs has clinical value in diagnosing and assessing the severity of brain injury in preterm infants.

Relation between amniotic fluid infection or cytokine levels and hearing screen failure in infants at 32 wk gestation or less.

BACKGROUND: To determine whether the presence of intra-amniotic infection and elevated proinflammatory cytokine levels in amniotic fluid (AF) are associated with failure in the newborn hearing screen (NHS) test in very preterm neonates. METHODS: This is a retrospective cohort study of 112 premature singleton neonates born to women with preterm labor or preterm premature rupture of membranes at ≤32 wk. AF obtained through amniocentesis was cultured, and interleukin-6 (IL-6) and IL-8 levels were determined. RESULTS: Fourteen (12.5%) neonates failed the NHS test. The prevalence of a positive AF culture was 40% (45/112). Multiple logistic regression analyses indicated that intra-amniotic infection was significantly associated with failure in the NHS test after adjusting for baseline covariates such as maternal white blood cell count (WBC) and periventricular leukomalacia. However, the IL-6 and IL-8 levels in AF were not significantly associated with hearing screen failure. Moreover, neither gestational age at birth nor birth weight was associated with NHS failure. CONCLUSION: The presence of intra-amniotic infection, but not elevated levels of AF IL-6 and IL-8, may contribute to the risk for failure in the NHS test in very preterm neonates. This finding suggests that intra-amniotic infection in utero might contribute to the development of congenital sensorineural hearing loss.

Patterns of increases in interleukin-6 and C-reactive protein as predictors for white matter injury in preterm infants.

BACKGROUND: The aim of this study was to determine whether patterns of increases in serum interleukin-6 (IL-6) and C-reactive protein (CRP) levels at birth were associated with the development of white matter injury (WMI) in preterm infants with a fetal inflammatory response (FIR). METHODS: One hundred infants who were born at <32 weeks gestation and had funisitis, as determined by histological evidence of FIR, were studied. Infants were divided into four groups according to IL-6 and CRP levels at birth, with cut-off values of 200 pg/mL and 0.4 mg/dL, respectively. We compared the incidence of WMI, determined by MRI at term-equivalent age, among these groups. RESULTS: The number of infants in each group was 12, 43, 0, and 45 in the high IL-6 and high CRP (HH) group, high IL-6 and low CRP (HL) group, low IL-6 and high CRP (LH) group, and low IL-6 and low CRP (LL) group, respectively. The incidence of WMI was significantly higher in the HH group than in the HL group and LL group (83%, 40%, and 34%, respectively). Multiple logistic regression analysis revealed that a combined elevation in IL-6 and CRP levels was an independent predictor for the development of WMI (odds ratio, 8.3). CONCLUSION: A combined elevation in serum IL-6 and CRP levels at birth was associated with the development of WMI in preterm infants with FIR.

Glial fibrillary acidic protein as a biomarker for periventricular white matter injury.

OBJECTIVE: Periventricular white matter injury (PWMI), a precursor of cerebral palsy, traditionally is not diagnosed until 6 weeks of life by head ultrasound scanning. We sought to determine whether early neonatal glial fibrillary acidic protein (GFAP) levels could identify PWMI in low birthweight (<2500 g) infants. STUDY DESIGN: Each case with PWMI on head ultrasound scanning at 6 weeks of life from April 2009 to April 2011 was matched by gestational age and mode of delivery to 2 subsequent neonates with a normal head ultrasound scan. GFAP was measured in cord blood at birth, at neonatal intensive care unit admission, and on days 1-4 of life. RESULTS: During this 2-year period, 21 cases with PWMI with gestational age 27.4 ± 3.3 weeks were compared with 42 control infants. The incidence of cesarean delivery was 61.9% in both groups. GFAP was not significantly different in cord blood or at neonatal intensive care unit admission but was significantly elevated on day 1 (median, 5-95%; 0, 0-0.98 ng/mL cases; 0, 0-0.06 ng/mL control infants; P = .03), day 2 (0, 0-1.21 ng/mL; 0, 0-0.05 ng/mL, respectively; P = .02), day 3 (0.05, 0-0.33 ng/mL; 0, 0-0.04 ng/mL, respectively; P = .004), and day 4 (0.02, 0-1.03 ng/mL; 0, 0-0.05 ng/mL, respectively; P < .001). The odds of the development of PWMI significantly increased with increasing levels of GFAP from day 1-4 of life when adjustment was made for preeclampsia, antenatal steroid administration, and neonatal chronic lung disease. CONCLUSION: The ability to predict PWMI with a blood test for GFAP shortly after birth opens the possibility for rapid identification of infants for early intervention and provides a benchmark for the qualification of new therapies to improve neurodevelopmental outcomes.

[Methods of diagnostic, differential diagnostic and criteria of the prognosis of hypoxemic-ischaemic brain damage of premature born in acute period].

The research is devoted to establishing of early diagnostic, differential-diagnostic criteria and the prognosis of hypixemic-ischaemic damage of central nervous system (that differs due to characteristics and the degree of complexity) of preliminary-born in acuity on the basis of their complex interdisciplinary research (anamnesis, neurological, clinical, instrumental--neurovoiceprint, immune-enzyme, in particular the dynamics of quantity level changes of brain-derived neurotropic factor in blood serum).

The absolute nucleated red blood cell (aNRBC) count at birth is not an indicator for retinopathy of prematurity (ROP).

OBJECTIVE: To establish the reproducibility of a published observation by Lubetzky et al. that infants affected by retinopathy of prematurity (ROP) had higher absolute nucleated red blood cell (aNRBC) counts than those unaffected. The authors suggested that infants exposed to intrauterine hypoxia are at higher risk for ROP. We attempted to verify this reported relationship of ROP with the aNRBCs at birth and hypothesized that infants with ROP ≥ stage 2 have higher aNRBCs at birth. STUDY DESIGN: We report a retrospective 1:1 case matched analysis where cases had a diagnosis of grade II ROP or worse and matching infants had confirmed stage I or no ROP. Eligible infants had birth weights of 501 to 1500 g and were discharged alive from 1st January 2000 to 31st December 2008. Wilcoxon's signed rank test was performed for continuous comparisons. This study was approved by two local Institutional Review Boards. RESULT: In all, 66 matched pairs were analyzed. When comparing aNRBCs there was no statistically significant relationship (w=-0.265, P=0.791) between the ROP affected group (M=4550, s.d.=7342) and the unaffected group (M=5287, s.d.=6524). CONCLUSION: We are unable to support the previously reported relationship of aNRBCs with ROP. Our population was three times larger, had higher aNRBCs and less retinopathy than previously reported. A biological principle of cause and effect or predisposition to ROP as reflected by aNRBCs should have been easier for us to demonstrate, if it existed.

Neonatal absolute nucleated red blood cell counts do not predict the development of cystic periventricular leukomalacia.

BACKGROUND: Infants with severe intraventricular-periventricular hemorrhage (IVH) have higher absolute nucleated red blood cell counts (aNRBC) at birth (a marker of intrauterine hypoxia) than controls. Periventricular leukomalacia (PVL) is known to be associated with prenatal and postnatal events. Whether PVL is also linked to intrauterine hypoxia is unknown. OBJECTIVES: To test the hypothesis that infants with PVL have higher aNRBC counts at birth than controls. METHODS: We studied 14 very low birth weight infants with PVL and compared them with 14 pair-matched controls without PVL. Head ultrasound scans were performed in all infants on days 3-5 and 21-25 of life. Paired tests, Fisher exact tests and stepwise logistic regression were performed for analysis. RESULTS: The groups were similar for gestational age (GA), birth weight (BW), prolonged rupture of membranes (PROM), Apgar scores, IVH, and aNRBC counts. PVL correlated significantly with low partial pressure of CO2 (PCO2) and IVH (P < 0.01). In logistic regression, when GA, gender, PROM, antenatal steroid therapy, 1 (or 5) minute Apgar scores, IVH grade, nosocomial sepsis, patent ductus arteriosus, necrotizing enterocolitis (NEC), need for pressors, aNRBC counts and lowest PCO2 were used as independent variables, PCO2 (P = 0.002), IVH grade (P= 0.001), GA (P = 0.038), NEC (P = 0.061) and use of dopamine (P = 0.010) remained in the analysis (total R2 = 68.2%). CONCLUSIONS: In contrast to severe IVH, aNRBC counts do not predict the development of PVL.

Erythropoietin-loaded oligochitosan nanoparticles for treatment of periventricular leukomalacia.

In this study, a single intraperitoneal injection of erythropoietin (EPO) loaded oligochitosan nanoparticles (epo-NPs) (average diameter 266 nm) was investigated as a treatment for periventricular leukomalacia (PVL). Nanoparticles were fabricated using a gelation technology process. PVL rats models were prepared to examine the therapeutic efficacy of epo-NPs and analyze the mechanism by which epo-NPs protect white matter. The metabolization of epo-NPs in the liver was also investigated. The pathology and behavioral data show that this single injection of a low quantity of epo-NPs had an excellent therapeutic effect on the rat model of PVL. The EPO release curve in phosphate buffered saline solution was a good fit with the zero-order kinetics distribution and was maintained at around 25% in 48 h. In vivo experiments demonstrated that 50 IU/kg epo-NPs had the same effect as a 5000 IU/kg direct injection of free EPO. Nanoparticles prolonged the time course of EPO metabolization in the liver and the stable release of EPO from the nanoparticles kept the plasma concentration of EPO at around 100 IU/ml during the 8-12h post-injection. Therefore, we suggest that oligochitosan based nanoparticles are an effective vehicle for drug delivery.

Day 1 serum lactate values in preterm infants less than 32 weeks gestation.

Base deficit and serum lactate concentrations may be important prognostic indicators in preterm infants. We sought to (1) determine the relationship between day 1 serum lactate values and base deficit and (2) determine the relationship between day 1 biochemical parameters and adverse outcome in preterm infants <32 weeks. This was a retrospective study of all patients less than 32 weeks gestation admitted to neonatal intensive care unit over a 6-month period. All blood gases performed during the first 24 h post delivery were analysed. Adverse outcome was defined as death, severe (grade 3 or 4) intraventricular haemorrhage or periventricular leukomalaica on cranial ultrasonography. Patients were excluded if there was a known lethal malformation or cardiac defect. Seventy-two infants had a total of 473 lactate levels performed in the first 24 h. Mean (SD) gestational age was 29 (2.3) weeks, mean (SD) birth weight 1.28 (0.42) kg. Mean (SD) lactate values in first 6 h was 4.63 (3.69), at 12 h 3.08 (2.6), at 18 h 2.47 (2.68) and 2.08 (2.74) mmol/l at 24 h. There was a strong correlation between lactate values and base deficit values (R value 0.8, p < 0.01). Mean base deficit values at 6 h were 5.9 (4.5), at 12 h 3.8 (3.9), at 18 h 3.6 (3.1) and at 24 h 4.1 (3.8) mmol/l. A single lactate value greater than 5.6 mmol/l had a sensitivity of 100% and specificity of 85% of identifying adverse outcome. Persistently elevated or worsening lactates were associated with adverse outcome. There is a strong correlation between lactate values and base deficit on day 1 of life. Serial lactate measurements greater than 5.6 mmol/l predict adverse outcome and may aid the clinician in bedside decision making.

High postnatal oxidative stress in neonatal cystic periventricular leukomalacia.

Oxidative stress plays an important role in cystic periventricular leukomalacia (PVL). We performed a case-control study of preterm infants delivered at <35 weeks of gestation between January 2003 and December 2006. Patients were stratified into three groups, according to age at which cysts were initially identified: 10 days old (early cystic PVL; n=10), >10 days old (late cystic PVL; n=12); and no cystic PVL (controls; n=22). Serum total hydroperoxide, biological antioxidant potential and oxidative stress index (calculated as total hydroperoxide/biological antioxidant potential) were measured within 3h after birth. Frequencies of preterm rupture of membrane and chorioamnionitis were significant higher in early cystic PVL than in late cystic PVL or controls. Duration of oxygen treatment and mechanical ventilation and frequency of apnea were significantly higher in late cystic PVL than in controls or early cystic PVL. Serum total hydroperoxide levels and oxidative stress index were significantly higher in early cystic PVL than in late cystic PVL or controls (p<0.05, respectively). Postnatal duration until cyst identification displayed a significant negative correlation with oxidative stress index and total hydroperoxide level (r=-0.497, p<0.05; r=-0.50, p<0.05, respectively). These findings suggest that early onset of cystic PVL might be due to either antenatal or intrapartum factors, but late onset might be due to postnatal factors. In the pathophysiology and therapy of cystic PVL, oxidative stress and onset timing appear crucial. This is the first study to reveal that neonates experiencing much more oxidative stress at birth show earlier onset of cystic PVL.

Proinflammatory cytokine-receptor interaction model improves the predictability of cerebral white matter injury in preterm infants.

Proinflammatory cytokines have been variably linked to development of cerebral white matter injury (WMI) in preterm infants. Because soluble receptors tightly control cytokine bioactivity, we modeled cytokine-receptor interaction as a predictor of WMI. Plasma from 100 preterm infants was assayed for cytokines (tumor necrosis factor alpha, interleukin (IL-1beta, IL-6) and their soluble receptors (sTNF-RI), sTNF-RII, sIL-1RA, and sIL-6R). Cranial ultrasound (US) results were correlated with cytokine and receptor concentrations individually and with cytokine-receptor interaction models (PROC LOGISTIC; SAS Software). Receiver operating characteristic curves were constructed to determine the predictability of WMI. Fifty-two infants with normal US exams were compared with 21 infants with evidence of WMI. There was no association between individual cytokine or receptor concentrations and the development of WMI. However, modeling cytokines with their soluble receptors significantly improved the predictability of WMI. We concluded that consideration of cytokine-receptor interaction may be more important than individual cytokine concentrations alone in determining the role of inflammation in the pathogenesis of WMI in preterm infants.

[Dynamic observation of hormonal characteristics in the newborn babies with periventricular leukomalacia during their first week of lives].

The problem of peculiarity of hormonal adaptation in newborn babies with periventricular leucomalacia--a condition that causes lifelong disability, in spite of its scientific and practical value is not adequately explored. The aim of the research was to investigate hormonal characteristics in the newborn babies with periventricular leucomalacia and to determine clinical and laboratory criteria for early prognosis of periventricular leucomalacia. Dynamic observation was conducted on 48 newborn babies who had acute and traumatic periventricular leucomalacia. Concentration of thyrotrophic hormone (TTH), tiroxine (T4) and triodtironin (T3) were determined in venous blood of the newborn babies on their first and fifth days of life. Cortisol was determined by the radioimmune method (RIA). The investigation revealed definite normal-adaptational reactions. Changes of hormonal traumatic periventricular leucomalacia, manifested in reduction of TTG, T3 level; concentration of T4 was moderately high.

Circulatory disturbances during the first postnatal 24 hours in extremely premature infants 25 weeks or less of gestation with histological fetal inflammation.

AIM: To investigate the effect of pre-existing fetal inflammation on hemodynamics during the first postnatal 24 h in extremely premature infants or= 3 than infants with no fetal inflammation (49% vs 17%) (P=0.04). Infants with fetal inflammation had significantly higher heart rate (P=0.005), catecholamine index (P=0.019) and volume load (P=0.021). CONCLUSION: Histological evidence of fetal inflammation in extremely premature infants is associated with circulatory disturbances over the first 24 h of life and increases in the incidence of IVH >or= 3.

Increased inflammatory markers are associated with early periventricular leukomalacia.

The aim of the study was to investigate whether inflammatory markers are associated with the occurrence of periventricular leukomalacia (PVL). Superoxide (O(2) (-)) production of neutrophils and plasma antioxidative superoxide dismutase (SOD) activity in umbilical cord blood were studied. Participants were preterm infants with early PVL (n=6; three males, three females; mean birthweight 1458g [SD 517], range 620-2040g; mean gestational age 29.8wks [SD 2.9], range 27-34wks); and preterm control infants without PVL (n=10; five males, five females; mean birthweight 1838g [SD 664], range 925-2748g; mean gestational age 30.6wks [SD 3.1], range 26-34wks). In addition, pro-inflammatory cytokine levels were measured in the umbilical cord blood. N-formyl-methionyl-leucyl-phenylalanine-induced O(2) (-) production by neutrophils in infants with early PVL was significantly higher than that in the control group. In contrast, there was no significant difference in concentrations of copper/zinc-SOD and SOD activity between groups. Concentrations of interleukin (IL)-1beta and tumour necrosis factor-alpha (but not IL-6, IL-8, or granulocyte-colony stimulating factor) were significantly higher in infants with early PVL than in control infants. The excess O(2) (-) produced by activated neutrophils with increased pro-inflammatory cytokine production could play a role in the molecular cascade leading to white matter damage in PVL.

Relationship between serum lactate level and periventricular leukomalacia.

In a case control study, we evaluated the serum lactate levels during the early days of life in preterm infants with periventricular leukomalacia (PVL), who were presumed to have suffered injury around birth. Thirteen infants diagnosed by ultrasonography as suffering from cystic PVL during the neonatal period and 26 normally developed infants matched by gestational age were enrolled in the study. The serum lactate level was measured repeatedly during the 72 h after birth. The mean serum lactate levels on admission were 2.95+/-0.43 and 3.21+/-0.29 mmol/L in the PVL and control groups, respectively. There was no statistically significant difference in the serum lactate level between the groups at any point during the first 72 h after birth. In conclusion, the serum lactate level was not elevated in preterm infants with PVL suggesting that the serum lactate level is not a useful predictor for the development of PVL in infants.