Nucleated red blood cells are a direct response to mediators of inflammation in newborns with early-onset neonatal sepsis

Nucleated red blood cells as a novel biomarker in the diagnosis and prediction of sepsis severity in children

Introduction

Sepsis is a vitally serious disease leading to high mortality. Nucleated red blood cells (NRBCs) are present in some noninfectious diseases, but the relationship between NRBCs and sepsis in children remains unknown. The purpose of this study was to compare the clinical characteristics and outcomes of sepsis with positive NRBCs and negative NRBCs in children, and to further explore whether the count of NRBCs has a relationship with the severity of sepsis.

Methods

We enrolled children with sepsis who were admitted to the Children's Hospital of Chongqing Medical University between January 2020 and December 2022. The children's clinical data, laboratory data and outcomes were recorded and analyzed.

Results

One hundred and fifteen children met the inclusion criteria in our study. Compared to negative NRBCs patients, the C-reactive protein, alanine transaminase, urea nitrogen values, mortality rate and length of hospitalization were found to be significantly increased, while platelet counts, and hemoglobin were significantly decreased in sepsis patients with positive NRBC (P < 0.05). Receiver operating characteristic (ROC) curves analysis showed that the optimal cutoff value of the NRBC count in the diagnosis of severe sepsis was 3, with a sensitivity of 87.5% and specificity of 94.9%. The area under the ROC curve was 0.877 (95% CI: 0.798-0.957).

Discussion

These findings demonstrated that NRBC count has the potential to be a biomarker for the diagnosis of sepsis in children, especially an NRBC count greater than 3, which may predict the severity and poor prognosis in children suffering from sepsis.

Plasma E-selectin and kallistatin as predictive markers of histologic chorioamnionitis in women with preterm premature rupture of membranes

PROBLEM

We aimed to assess the predictive potential of 12 plasma biomarkers to predict acute histologic chorioamnionitis (HCA) in women with preterm premature rupture of membranes (PPROM) and to develop multi-biomarker panels based on these biomarkers in combination with widely used conventional laboratory markers.

METHOD OF STUDY

This was a retrospective cohort study involving 81 singleton pregnant women (24-34 weeks of gestation) who delivered within 96 h of blood sampling. White blood cell (WBC) count, differential counts, and C-reactive protein (CRP) levels were measured at admission. The levels of DKK-3, Fas, haptoglobin, IGFBP-2, kallistatin, MIP-1α, MMP-2, MMP-8, pentraxin 3, progranulin, E-selectin, and P-selectin were evaluated by ELISA using stored plasma samples. The primary outcome measure was acute HCA.

RESULTS

Multivariate analyses showed that low plasma E-selectin and kallistatin levels were independently associated with HCA occurrence after adjusting for gestational age. Using a stepwise regression analysis, a multi-biomarker panel comprising plasma E-selectin, serum CRP, and WBC was developed, which provided a good prediction of acute HCA in women with PPROM (area under the curve [AUC], 0.899), with a significantly higher AUC than that of any single variable included in the panel (P<0.05). The plasma levels of DKK-3, Fas, haptoglobin, IGFBP-2, MIP-1α, MMP-2, MMP-8, pentraxin 3, and P-selectin were not significantly associated with HCA occurrence.

CONCLUSIONS

This study identified E-selectin and kallistatin as potential plasma biomarkers associated with acute HCA in women with PPROM. Their combined analysis with serum CRP and WBC counts significantly improved acute HCA diagnosis. This article is protected by copyright. All rights reserved.

Postpartum assessment of fetal inflammatory response syndrome in a preterm population with premature rupture of membranes: A Romanian study

Fetal inflammatory response syndrome is associated with increased neonatal morbidity and mortality. The aim of the present study was to evaluate the dynamics of the plasmatic value of pro-inflammatory cytokines: tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and neutrophil activating peptide 78 (ENA-78) and the anti-inflammatory cytokine IL-10 in the first and third day of life and the correlation with neonatal morbidities and mortality. The current research was designed as a prospective case control study included 80 neonates hospitalized at the 3rd level Neonatal Intensive Care Unit (NICU), 1st Gynecology Clinic, County Emergency Hospital, Cluj-Napoca, Romania. For each patient, the following parameters were noted: pH at first hour of life, oxygen saturation, fraction of inspired oxygen (FiO2) and duration of premature rupture of the membranes (PROM). Measurements of cytokines were determined from venous blood in the first and third day of life. The values of all cytokines were higher in the newborns from mothers with PROM. The value of IL-6 in the study group was higher compared to the controls during the first day of life and met the highest value in necrotizing enterocolitis (NEC). ENA-78 was higher in the study group (P=0.037) and decreased during the first 3 days of life. The highest value of ENA-78 was found in the neonates with cerebral hemorrhage. IL-10 also had values with a significant difference in the first day of life between both groups (P=0.02). IL-10 had the highest value in sepsis cases. In conclusion, among the inflammatory parameters that were evaluated, the dynamics of ENA-78 and IL-10 were found to influence the neonatal prognosis of newborns with PROM. The decrease in ENA-78 and IL-10 during the third day of life could suggest the evolution towards the ending of the inflammatory process and an increase in the survival rate was noted.

PERINATAL CENTRILOBULAR HEPATIC NECROSIS IN GIANT PANDAS (AILUROPODA MELANOLEUCA): A RETROSPECTIVE STUDY

Between 1983 and 2012, six giant panda cubs (Ailuropoda melanoleuca) born at a zoological institution were stillborn or died between the ages of 3 and 200 h. Two of the six cubs had panhepatic centrilobular hepatic necrosis (CHN), granulocytic extramedullary hematopoiesis (GEM), positive liver culture for Staphylococcus species, and terminal liver failure. Another low-weight cub was administered oxygen therapy immediately after birth and developed hyaline membranes in air spaces and hepatic necrosis restricted to the hilar region. A retrospective analysis of liver and lung lesions, pulmonary microanatomy, blood-gas barrier ultrastructure, and hepatic myofibroblast proliferation was conducted on the six cubs. Neonates with CHN had concurrent severe periportal GEM accompanied by severe myofibroblast proliferation. The pulmonary blood-gas barrier was markedly increased in one cub with CHN. Developmentally, the lungs of all but one cub were at the late saccular stage, and the lowest-weight cub was in early saccular stage, consistent with immaturity, and had pneumonia comparable to neonatal respiratory distress syndrome (RDS). Stage of lung development was eliminated as the primary factor leading to CHN. The pathogenesis of CHN in these neonates is proposed to be transformation of hepatic stellate cells to myofibroblasts initiating blockage and microvascular constriction of hepatic sinusoids, resulting in insufficient perfusion and cellular hypoxia of hepatocytes surrounding central veins in acinar zone 3.

Chorioamnionitis and Risk for Maternal and Neonatal Sepsis: A Systematic Review and Meta-analysis

OBJECTIVE

To estimate the risk of maternal and neonatal sepsis associated with chorioamnionitis.

DATA SOURCES

PubMed, BIOSIS, and ClinicalTrials.gov databases were systematically searched for full-text articles in English from inception until May 11, 2020.

METHODS OF STUDY SELECTION

We screened 1,251 studies. Randomized controlled trials, case-control, or cohort studies quantifying a relationship between chorioamnionitis and sepsis in mothers (postpartum) or neonates born at greater than 22 weeks of gestation were eligible. Studies were grouped for meta-analyses according to exposures of histologic or clinical chorioamnionitis and outcomes of maternal or neonatal sepsis.

TABULATION, INTEGRATION, AND RESULTS

One hundred three studies were included, and 55 met criteria for meta-analysis (39 studies of preterm neonates, 10 studies of general populations of preterm and term neonates, and six studies of late preterm and term neonates). Study details and quantitative data were abstracted. Random-effects models were used to generate pooled odds ratios (ORs); most studies only reported unadjusted results. Histologic chorioamnionitis was associated with confirmed and any early-onset neonatal sepsis (unadjusted pooled ORs 4.42 [95% CI 2.68-7.29] and 5.88 [95% CI 3.68-9.41], respectively). Clinical chorioamnionitis was also associated with confirmed and any early-onset neonatal sepsis (unadjusted pooled ORs 6.82 [95% CI 4.93-9.45] and 3.90 [95% CI 2.74-5.55], respectively). Additionally, histologic and clinical chorioamnionitis were each associated with higher odds of late-onset sepsis in preterm neonates. Confirmed sepsis incidence was 7% (early-onset) and 22% (late-onset) for histologic and 6% (early-onset) and 26% (late-onset) for clinical chorioamnionitis-exposed neonates. Three studies evaluated chorioamnionitis and maternal sepsis and were inconclusive.

CONCLUSION

Both histologic and clinical chorioamnionitis were associated with early- and late-onset sepsis in neonates. Overall, our findings support current guidelines for preventative neonatal care. There was insufficient evidence to determine the association between chorioamnionitis and maternal sepsis.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO, CRD42020156812.

The role of CD71+ erythroid cells in the regulation of the immune response

Complex regulation of the immune response is necessary to support effective defense of an organism against hostile invaders and to maintain tolerance to harmless microorganisms and autoantigens. Recent studies revealed previously unappreciated roles of CD71⁺ erythroid cells (CECs) in regulation of the immune response. CECs physiologically reside in the bone marrow where erythropoiesis takes place. Under stress conditions, CECs are enriched in some organs outside of the bone marrow as a result of extramedullary erythropoiesis. However, the role of CECs goes well beyond the production of erythrocytes. In neonates, increased numbers of CECs contribute to their vulnerability to infectious diseases. On the other side, neonatal CECs suppress activation of immune cells in response to abrupt colonization with commensal microorganisms after delivery. CECs are also enriched in the peripheral blood of pregnant women as well as in the placenta and are responsible for the regulation of feto-maternal tolerance. In patients with cancer, anemia leads to increased frequency of CECs in the peripheral blood contributing to diminished antiviral and antibacterial immunity, as well as to accelerated cancer progression. Moreover, recent studies revealed the role of CECs in HIV and SARS-CoV-2 infections. CECs use a full arsenal of mechanisms to regulate immune response. These cells suppress proinflammatory responses of myeloid cells and T-cell proliferation by the depletion of ʟ-arginine by arginase. Moreover, CECs produce reactive oxygen species to decrease T-cell proliferation. CECs also secrete cytokines, including transforming growth factor β (TGF-β), which promotes T-cell differentiation into regulatory T-cells. Here, we comprehensively describe the role of CECs in orchestrating immune response and indicate some therapeutic approaches that might be used to regulate their effector functions in the treatment of human conditions.

Prognostic impacts of peripheral blood erythroblasts after single-unit cord blood transplantation

INTRODUCTION

The appearance of erythroblasts (EBLs) in peripheral blood occurs in a variety of serious conditions and has been associated with mortality in critically ill patients. However, the incidence, risk factor, and outcomes of EBLs after cord blood transplantation (CBT) remain unclear.

METHODS

We have investigated the impact of EBLs on transplant outcomes on 225 adult patients who underwent single-unit CBT at our single institute.

RESULTS

The cumulative incidences of EBL ≥200 × 10⁶ /L and EBL ≥1000 × 10⁶ /L at 60 days after CBT were 17% and 4%, respectively, detected after a median of 35 days and 36.5 days. Multivariate analysis using erythroblastosis as time-dependent covariates demonstrated the significant association of EBL ≥1000 × 10⁶ /L, but not EBL ≥200 × 10⁶ /L, with the development of grade III-IV acute graft-versus-host disease (GVHD, hazard ratio [HR]: 18.56; P < .001), higher nonrelapse mortality (HR: 13.38; P < .001), and overall mortality (HR: 4.97; P = .001).

CONCLUSION

These data suggested that higher levels of EBLs were recognized as a significant risk factor for severe acute GVHD and mortality after single-unit CBT. Higher levels of EBLs may serve as a surrogate marker for poor single CBT outcomes.

Association of nucleated red blood cell count with mortality among neonatal intensive care unit patients

BACKGROUND

Nucleated red blood cells (nRBCs) are associated with adverse outcomes for pediatric and adult intensive care patients.

METHODS

The association between nRBC count and mortality was examined in an observational cohort of patients admitted to the neonatal intensive care unit from December 2015-December 2018.

RESULTS

Among the 1059 patients with at least one nRBC count obtained, 45 infants (4.2%) experienced in-hospital mortality prior to NICU discharge, the primary outcome measured in this study. Infants with any nRBC count >0 had a significantly higher risk of mortality (5.3% [45/849] vs. 0% [0/351], p < 0.001 by Fisher exact), and time to mortality decreased with higher nRBC counts (Spearman correlation -0.59, p < 0.001). The association between nRBC count and mortality remained significant even when restricting only to infants who were older than 7 days at time of nRBC count.

CONCLUSION

Among neonatal intensive care unit patients, including those >7 days old, nRBCs are associated with significantly elevated mortality risk. A prospective study to better characterize clinical co-variants is necessary to better establish the use of nRBCs as a predictor of mortality.

Nucleated Red Blood Cells: Could They Be Indicator Markers of Illness Severity for Neonatal Intensive Care Unit Patients?

Background: We aimed to assess whether nucleated red blood cells (NRBCs) count could serve as a diagnostic and prognostic biomarker for morbidity and mortality in critically ill neonates. Methods: The association between NRBCs count and neonatal morbidity and mortality was evaluated in an observational cohort of critically ill neonates hospitalized in our neonatal intensive care unit over a period of 69 months. The discriminative ability of NRBCs count as diagnostic and prognostic biomarkers was evaluated by performing the Receiver Operating Characteristics (ROC) curve analysis. Results: Among 467 critically ill neonates included in the study, 45 (9.6%) of them experienced in-hospital mortality. No statistically significant difference was found with regards to NRBCs count between survivors and non-survivors, although the median value for NRBCs was sometimes higher for non-survivors. ROC curve analysis showed that NRBCs is a good discriminator marker for the diagnosis of perinatal hypoxia in neonates with area under the curve (AUC) [AUC 0.710; 95% confidence interval (CI), 0.660–0.759] and predominantly in preterm neonates (AUC 0.921 (95% CI, 0.0849–0.0993)) by using a cut-off value of ≥11.2%, with 80% sensitivity and 88.7% specificity. NRBCs also revealed significant prognostic power for mortality in septic neonates (AUC 0.760 (95% CI, 0.631–0.888)) and especially in preterms with sepsis (AUC 0.816 (95% CI, 0.681–0.951)), with cut-off value ≥ 1%, resulting in 81.6% sensitivity and 78.1% specificity. Conclusion: NRBCs count may be included among the early diagnostic and prognostic markers for sick neonates.

The fetal inflammatory response syndrome: the origins of a concept, pathophysiology, diagnosis, and obstetrical implications

The fetus can deploy a local or systemic inflammatory response when exposed to microorganisms or, alternatively, to non-infection-related stimuli (e.g., danger signals or alarmins). The term "Fetal Inflammatory Response Syndrome" (FIRS) was coined to describe a condition characterized by evidence of a systemic inflammatory response, frequently a result of the activation of the innate limb of the immune response. FIRS can be diagnosed by an increased concentration of umbilical cord plasma or serum acute phase reactants such as C-reactive protein or cytokines (e.g., interleukin-6). Pathologic evidence of a systemic fetal inflammatory response indicates the presence of funisitis or chorionic vasculitis. FIRS was first described in patients at risk for intraamniotic infection who presented preterm labor with intact membranes or preterm prelabor rupture of the membranes. However, FIRS can also be observed in patients with sterile intra-amniotic inflammation, alloimmunization (e.g., Rh disease), and active autoimmune disorders. Neonates born with FIRS have a higher rate of complications, such as early-onset neonatal sepsis, intraventricular hemorrhage, periventricular leukomalacia, and death, than those born without FIRS. Survivors are at risk for long-term sequelae that may include bronchopulmonary dysplasia, neurodevelopmental disorders, such as cerebral palsy, retinopathy of prematurity, and sensorineuronal hearing loss. Experimental FIRS can be induced by intra-amniotic administration of bacteria, microbial products (such as endotoxin), or inflammatory cytokines (such as interleukin-1), and animal models have provided important insights about the mechanisms responsible for multiple organ involvement and dysfunction. A systemic fetal inflammatory response is thought to be adaptive, but, on occasion, may become dysregulated whereby a fetal cytokine storm ensues and can lead to multiple organ dysfunction and even fetal death if delivery does not occur ("rescued by birth"). Thus, the onset of preterm labor in this context can be considered to have survival value. The evidence so far suggests that FIRS may compound the effects of immaturity and neonatal inflammation, thus increasing the risk of neonatal complications and long-term morbidity. Modulation of a dysregulated fetal inflammatory response by the administration of antimicrobial agents, anti-inflammatory agents, or cell-based therapy holds promise to reduce infant morbidity and mortality.

Association of Histological and Clinical Chorioamnionitis With Neonatal Sepsis Among Preterm Infants: A Systematic Review, Meta-Analysis, and Meta-Regression

Chorioamnionitis (CA) is considered a key risk factor for very preterm birth and for developing early onset sepsis (EOS) in preterm infants, but recent data suggest that CA might be protective against late onset sepsis (LOS). We performed a systematic review and meta-analysis of studies exploring the association between CA and sepsis. A comprehensive literature search was performed in PubMed/MEDLINE and EMBASE, from their inception to December 1, 2018. A random-effects model was used to calculate odds ratios (OR) and 95% confidence intervals (CI). Sources of heterogeneity were analyzed by subgroup and meta-regression analyses. The following categories of sepsis were analyzed: EOS, LOS, unspecified onset sepsis (UOS), culture-proven, and clinical sepsis. CA was subdivided into clinical and histological chorioamnionitis. Funisitis was also analyzed. We found 3,768 potentially relevant studies, of which 107 met the inclusion criteria (387,321 infants; 44,414 cases of CA). Meta-analysis showed an association between any CA and any EOS (OR 4.29, CI 3.63-5.06), any LOS (OR 1.29, CI 1.11-1.54), and any UOS (OR 1.59, CI 1.11-1.54). Subgroup analysis showed that CA was associated with culture-proven EOS (OR 4.69, CI 3.91-5.56), clinical EOS (OR 3.58, CI 1.90-6.76), and culture-proven LOS (OR 1.31, CI 1.12-1.53), but not with clinical LOS (OR 1.52, CI 0.78-2.96). The presence of funisitis did not increase the risk of either EOS or LOS when compared with CA without funisitis. CA-exposed infants had lower gestational age (-1.11 weeks, CI -1.37 to -0.84) than the infants not exposed to CA. Meta-regression analysis showed that the lower gestational age of the CA group correlated with the association between CA and LOS but not with the association between CA and EOS. In conclusion, our data suggest that the positive association between chorioamnionitis and LOS may be modulated by the effect of chorioamnionitis on gestational age.

Emergence role of nucleated red blood cells in molecular response evaluation for chronic myeloid leukemia

Purpose

To investigate and evaluate the role of nucleated red blood cells (NRBCs) and other markers in predicting remission failure in chronic myeloid leukemia (CML) patients treated with imatinib.

Methods

Seventy-one CML patients with BCR-ABL(+) in bone marrow cells were selected for this study. Molecular response evaluations were done every three months according to the recommendations of European LeukemiaNet (ELN). Patients were defined as remission failure if BCR-ABL transcripts >10% after 6 months (T6), >1% after 12 months (T12), and >0.1% after 18 (T18) months of treatment. The logistic regression was used to determine the optimal cut-off point of each marker and test the association of marker level with remission failure.

Results

The median NRBC, white blood cells, blast cells, basophils, and platelets were declined parallel with the decreases of BCR-ABL transcripts in bone marrow cells after 6 months of treatment (P<0.001). In addition, NRBC was almost not found in the blood of patients who archived good response at T6, T12, and T18 time-points. Interestingly, patients with a high level of NRBC (cut-off: 0.003×10⁹/L) have higher BCR-ABL transcripts compared to others. The elevated NRBC at T6 (OR=6.49, P=0.042), T12 (OR=6.73, P=0.007), and T18 (OR=5.96, P=0.009) time-points was identified as an independent factor for the remission failure.

Conclusion

The results of this study showed that a high number of NRBC in peripheral blood of CML patients is associated with higher BCR-ABL transcripts in bone marrow cells. The elevated NRBC might serve as an independent marker for molecular remission failure in CML.

Nucleated red blood cells, critical illness survivors and postdischarge outcomes: a cohort study

Background

Little is known about risk factors associated with out-of-hospital outcomes in survivors of critical illness. We hypothesized that the presence of nucleated red blood cells in patients who survived critical care would be associated with adverse outcomes following hospital discharge.

Methods

We performed a two-center observational cohort study of patients treated in medical and surgical intensive care units in Boston, Massachusetts. All data were obtained from the Research Patient Data Registry at Partners HealthCare. We studied 2878 patients, age ≥ 18 years, who received critical care between 2011 and 2015 and survived hospitalization. The exposure of interest was nucleated red blood cells occurring from 2 days prior to 7 days after critical care initiation. The primary outcome was mortality in the 90 days following hospital discharge. Secondary outcome was unplanned 30-day hospital readmission. Adjusted odds ratios were estimated by multivariable logistic regression models with inclusion of covariate terms thought to plausibly interact with both nucleated red blood cells and outcome. Adjustment included age, race (white versus nonwhite), gender, Deyo–Charlson Index, patient type (medical versus surgical), sepsis and acute organ failure.

Results

In patients who received critical care and survived hospitalization, the absolute risk of 90-day postdischarge mortality was 5.9%, 11.7%, 15.8% and 21.9% in patients with 0/μl, 1–100/μl, 101–200/μl and more than 200/μl nucleated red blood cells respectively. Nucleated red blood cells were a robust predictor of postdischarge mortality and remained so following multivariable adjustment. The fully adjusted odds of 90-day postdischarge mortality in patients with 1–100/μl, 101–200/μl and more than 200/μl nucleated red blood cells were 1.77 (95% CI, 1.23–2.54), 2.51 (95% CI, 1.36–4.62) and 3.72 (95% CI, 2.16–6.39) respectively, relative to patients without nucleated red blood cells. Further, the presence of nucleated red blood cells is a significant predictor of the odds of unplanned 30-day hospital readmission.

Conclusion

In critically ill patients who survive hospitalization, the presence of nucleated red blood cells is a robust predictor of postdischarge mortality and unplanned hospital readmission.

Electronic supplementary material

The online version of this article (doi:10.1186/s13054-017-1724-z) contains supplementary material, which is available to authorized users.

Maternal and Placental Factors Associated with Congenital Hearing Loss in Very Preterm Neonates

BACKGROUND

Sensorineural hearing loss (SNHL) is a multifactorial disease that more frequently affects preterm newborns. Although a number of maternal conditions have been reported to be associated with preterm birth, little information is available concerning maternal risk factors for the development of SNHL. We aimed to identify maternal and placental risk factors associated with a "refer" result on the newborn hearing screening (NHS) test and subsequently confirmed SNHL in very preterm neonates.

METHODS

This retrospective cohort study included 267 singleton neonates who were born alive after ≤ 32 weeks. Histopathologic examination of the placenta was performed, and clinical data were retrieved from a computerized perinatal database. Cases with two abnormal findings, "refer" on the NHS test, and presence of SNHL on the confirmation test were retrospectively reviewed based on electronic medical records.

RESULTS

Forty-two neonates (15.7%) showed a "refer" result, and, on the confirmation test, permanent SNHL was identified in 1.87% (5/267) of all neonates. Multivariate regression analysis revealed that the presence of funisitis was independently associated with a "refer" on the NHS test, whereas use of antenatal corticosteroids was statistically significantly associated with a reduced incidence of "refer" on the screening test. Neither histologic chorioamnionitis nor prematurity (as defined by low gestational age and birth weight) was associated with a "refer" on the NHS test. By contrast, multivariate analysis with occurrence of SNHL as a dependent variable identified no significant associations with the parameters studied, probably owing to the small total number of neonates with permanent SNHL.

CONCLUSION

Presence of funisitis was significantly and independently associated with increased risk of abnormal NHS results, while administration of antenatal corticosteroids was related to a normal NHS result. These findings support the hypothesis that a systemic fetal inflammatory response, manifested as funisitis, might play a role in the pathogenesis of SNHL in preterm neonates.

Association of cord blood chemokines and other biomarkers with neonatal complications following intrauterine inflammation

BACKGROUND

Intrauterine inflammation has been associated with preterm birth and neonatal complications. Few reports have comprehensively investigated multiple cytokine profiles in cord blood and precisely identified surrogate markers for intrauterine inflammation.

AIM

To identify the cytokines and surrogate markers associated with intrauterine inflammation and subsequent neonatal complications.

PATIENTS AND METHODS

We analyzed cord blood samples from 135 patients admitted to the neonatal intensive care unit at Sasebo City General Hospital. We retrospectively determined the associations between the presence of neonatal complications and cord blood cytokines, prenatal factors, and laboratory data at birth. A total of 27 cytokines in the cord blood were measured using a bead-based array sandwich immunoassay.

RESULTS

Both Th1 and Th2 cytokine levels were low, whereas the levels of growth factors and chemokines were high. In particular, chemokines IL-8, MCP-1, and MIP-1α were significantly higher in very premature neonates when compared with more mature neonates. In addition, some have been shown to be associated with multiple neonatal complications, including patent ductus arteriosus (PDA), respiratory distress syndrome (RDS), and chronic lung disease (CLD). Similarly, the levels of N-terminal pro-brain natriuretic peptide, nucleated RBC, and urinary β2-microglobulin were associated with these complications and chemokine levels.

CONCLUSIONS

Our results suggest the association of inflammatory chemokines IL-8, MCP-1, and MIP-1α with intrauterine inflammation, premature birth, and neonatal complications in these perinatal subjects. Furthermore, the association of the aforementioned biomarkers with PDA, RDS, and CLD may help establish early diagnostic measures to predict such neonatal complications following intrauterine inflammation.

Nucleated Red Blood Cells as a Marker of Acute and Chronic Fetal Hypoxia in a Rat Model

OBJECTIVE

To examine the relationship between duration of fetal hypoxia, nucleated red blood cell (NRBC) count, and fetal growth.

METHODS

Pregnant rats were exposed to a severe hypoxia (9.5%-10% O₂) for varying time intervals (2, 6, 12, 24, 48, and 120 hours; n=4 for each time interval) immediately prior to delivery at term. Normoxic controls were exposed to room air (21% O₂) and matched for all other study variables (n=4 rats for each time interval). Pups were delivered via hysterotomy while maintaining exposure gas concentrations. Blood gas analysis and NRBC counts were performed, and fetal body and liver weights were recorded. Student's t test and simple regression were used for statistical analysis.

RESULTS

As the duration of hypoxia increased, fetal weight, liver weight, blood bicarbonate, and base excess levels decreased significantly; concomitantly, NRBC counts increased. This increase in NRBCs became statistically significant after 24 hours of exposure. After 48 hours of hypoxia there was a 2.5-fold rise in NRBC count, and after 120 hours of hypoxia there was a 4.5-fold rise in NRBC count over control levels. After 12 or more hours of hypoxia, fetal body weights were significantly reduced; 120 hours of hypoxia resulted in a 35% reduction in fetal body weight, a 34% reduction in fetal liver weight, and 356% increase in NRBC count.

CONCLUSION

In a pregnant rat model, chronic maternal hypoxia (≥24 hours) results in a significant increase in fetal NRBC counts as well as reduced fetal body weight and organ growth.

Short cervical lengths initially detected in mid-trimester and early in the third trimester in asymptomatic twin gestations: Association with histologic chorioamnionitis and preterm birth

Objective

To determine whether short cervical lengths (≤20 mm) that were initially detected in mid-trimester and early in the third trimester are independently associated with increased risks of subsequent histologic chorioamnionitis and spontaneous preterm birth (SPTB, defined as a delivery before 34 weeks) in asymptomatic women with twin pregnancies.

Material and methods

This is a prospective study including 292 consecutive asymptomatic women with twin gestations. Cervical length measurements were carried out at 20 to 24 weeks’ gestation and at 28 to 32 weeks’ gestation. Both placentas of each twin pair were examined histologically after delivery. The generalized estimation equations models and logistic regression analysis were used for statistical analyses.

Results

Multivariable generalized estimation equations analysis revealed that short cervical length at mid-trimester was independently associated with an increased risk for subsequent histologic chorioamnionitis, whereas short cervical length initially detected early in the third trimester was not. By using the likelihood of SPTB as an outcome variable, multivariable logistic regression analysis indicated that short mid-trimester cervical length and histologic chorioamnionitis were independently associated with a greater risk for SPTB. Similarly, based on the multivariable analysis, a short third trimester cervical length was independently and significantly associated with a greater risk for SPTB.

Conclusions

In asymptomatic women with twin pregnancies, a short mid-trimester cervical length is independently associated with an increased risk of both subsequent histologic chorioamnionitis and SPTB, whereas a short cervical length initially detected early in the third trimester is independently associated with preterm delivery, but not subsequent histologic chorioamnionitis.

Reference values for nucleated red blood cells and serum lactate in very and extremely low birth weight infants in the first week of life

STUDY PURPOSE

To provide reference values for nucleated red blood cells and serum lactate concentrations in very and extremely low birth weight (VLBW/ELBW) infants in the first week of life.

PATIENTS AND METHODS

Retrospective data analysis of serial, daily measurements of NRBC counts and serum lactate during the first 6days of life in VLBW and ELBW infants.

RESULTS

In total, 250 infants<1500g were included in this study. Intrauterine growth retardation (IUGR) was seen in 87 (34.8%) patients. Gestational age (GA) ranged from 23 to 35weeks (mean 29.0weeks) and birth weight (BW) was 320-1499g (mean 1047.9g). During hospital stay, 55 (22%) patients developed IVH and 55 children (22%) BPD. PVL was seen in 12 (4.8%) cases, ROP in 93 (37.2%) and NEC in only 1 (0.4%) patient. NRBC counts as well as serum lactate concentrations depended significantly on birth weight (p<0.01) and presence respectively absence of IUGR (p<0.01). Both NRBC counts and serum lactate concentrations declined constantly during the 6-day period (p<0.01), and both were highly inter-correlated (p<0.01).

CONCLUSIONS

This is one of only a very few studies that systematically and serially evaluated both NRBC counts and serum lactate concentration in VLBW and ELBW infants in the first 6days of life. Both parameters were significantly dependent on birth weight and the presence of IUGR. Moreover, a significant correlation between NRBC counts and serum lactate concentrations in this early period of life could be demonstrated. In future studies, the role of these readily available biomarkers in predicting important neonatal outcome parameters needs to be evaluated in a prospective manner.

Elevated Nucleated Red Blood Cells at Birth Predict Hemodynamically Significant Patent Ductus Arteriosus

We hypothesized that postnatal absolute nucleated red blood cell (aNRBC) counts would be elevated in premature infants with hemodynamically significant patent ductus arteriosus (PDA), reflecting intrauterine hypoxia. PDA severity was assessed and categorized echocardiographically. aNRBC counts were significantly correlated with ductal severity (Pearson correlation: P = .007). At the extremes, aNRBC levels were 3770 (728, 6015) hemodynamically significant PDA vs 865 (483, 2528) closed ductus.

Characterizing the hypomethylated DNA methylation profile of nucleated red blood cells from cord blood

AIM

To provide insight into fetal nucleated red blood cell (nRBC) development using genome-wide DNA methylation (DNAm) profiling.

MATERIALS & METHODS

The DNAm profile (Illumina 450K array) of cord blood (n = 7) derived nRBCs was compared with B cells, CD4 and CD8 T cells, natural killer cells, granulocytes, monocytes and placenta (n = 5).

RESULTS

nRBCs and placenta had similarly low array-wide DNAm compared with white blood cells, but their patterns of hypomethylation differed at biologically relevant subsets of the array. High interindividual variability in nRBC DNAm was driven by a negative association between DNAm and nRBC count.

CONCLUSION

nRBC hypomethylation is likely an epigenetic signature of erythropoiesis rather than of early development. Variability in nRBC DNAm may stem from differences in the cell population's maturity or hematopoietic source.

Non-Invasive Prediction of Histologic Chorioamnionitis in Women with Preterm Premature Rupture of Membranes

PURPOSE

To develop a model based on non-invasive clinical and ultrasonographic parameters for predicting the likelihood of subsequent histologic chorioamnionitis in women with preterm premature rupture of membranes (PPROM) and to determine whether the inclusion of invasive test results improves the predictive value of the model.

MATERIALS AND METHODS

This retrospective cohort study included 146 consecutive women presenting with PPROM (20-33 weeks). Transvaginal ultrasonographic assessment of cervical length was performed. Maternal serum C-reactive protein (CRP) levels and white blood cell (WBC) counts were measured after amniocentesis. Amniotic fluid (AF) obtained by amniocentesis was cultured, and interleukin-6 (IL-6) levels and WBC counts were determined. The primary outcome measure was histologic chorioamnionitis.

RESULTS

Risk scores based on serum CRP concentrations and gestational age (model 1) were calculated for each patient. The model was shown to have adequate goodness of fit and an area under the receiver operating characteristic curve (AUC) of 0.742. When including AF test results (e.g., AF IL-6 levels) in model 1, serum CRP concentrations were found to be insignificant, and thus, were excluded from model 2, comprising AF IL-6 levels and gestational age. No significant difference in AUC was found between models 1 and 2.

CONCLUSION

For women with PPROM, the newly developed model incorporating non-invasive parameters (serum CRP and gestational age) was moderately predictive of histologic chorioamnionitis. The inclusion of invasive test results added no predictive information to the model in this setting.

Neonatal CD71+ Erythroid Cells Do Not Modify Murine Sepsis Mortality

Sepsis is a major cause of neonatal mortality and morbidity worldwide. A recent report suggested that murine neonatal host defense against infection could be compromised by immunosuppressive CD71(+) erythroid splenocytes. We examined the impact of CD71(+) erythroid splenocytes on murine neonatal mortality to endotoxin challenge or polymicrobial sepsis and characterized circulating CD71(+) erythroid (CD235a(+)) cells in human neonates. Adoptive transfer or an Ab-mediated reduction in neonatal CD71(+) erythroid splenocytes did not alter murine neonatal survival to endotoxin challenge or polymicrobial sepsis challenge. Ex vivo immunosuppression of stimulated adult CD11b(+) cells was not limited to neonatal splenocytes; it also occurred with adult and neonatal bone marrow. Animals treated with anti-CD71 Ab showed reduced splenic bacterial load following bacterial challenge compared with isotype-treated mice. However, adoptive transfer of enriched CD71(+) erythroid splenocytes to CD71(+)-reduced animals did not reduce bacterial clearance. Human CD71(+)CD235a(+) cells were common among cord blood mononuclear cells and were shown to be reticulocytes. In summary, a lack of effect on murine survival to polymicrobial sepsis following adoptive transfer or diminution of CD71(+) erythroid splenocytes under these experimental conditions suggests that the impact of these cells on neonatal infection risk and progression may be limited. An unanticipated immune priming effect of anti-CD71 Ab treatment, rather than a reduction in immunosuppressive CD71(+) erythroid splenocytes, was likely responsible for the reported enhanced bacterial clearance. In humans, the well-described rapid decrease in circulating reticulocytes after birth suggests that they may have a limited role in reducing inflammation secondary to microbial colonization.

A "multi-hit" model of neonatal white matter injury: cumulative contributions of chronic placental inflammation, acute fetal inflammation and postnatal inflammatory events

OBJECTIVE

We sought to determine whether cumulative evidence of perinatal inflammation was associated with increased risk in a "multi-hit" model of neonatal white matter injury (WMI).

METHODS

This retrospective cohort study included very preterm (gestational ages at delivery <32 weeks) live-born singleton neonates delivered at Hutzel Women's Hospital, Detroit, MI, from 2006 to 2011. Four pathologists blinded to clinical diagnoses and outcomes performed histological examinations according to standardized protocols. Neurosonography was obtained per routine clinical care. The primary indicator of WMI was ventriculomegaly (VE). Neonatal inflammation-initiating illnesses included bacteremia, surgical necrotizing enterocolitis, other infections, and those requiring mechanical ventilation.

RESULTS

A total of 425 live-born singleton neonates delivered before the 32nd week of gestation were included. Newborns delivered of pregnancies affected by chronic chorioamnionitis who had histologic evidence of an acute fetal inflammatory response were at increased risk of VE, unlike those without funisitis, relative to referent newborns without either condition, adjusting for gestational age [odds ratio (OR) 4.7; 95% confidence interval (CI) 1.4-15.8 vs. OR 1.3; 95% CI 0.7-2.6]. Similarly, newborns with funisitis who developed neonatal inflammation-initiating illness were at increased risk of VE, unlike those who did not develop such illness, compared to the referent group without either condition [OR 3.6 (95% CI 1.5-8.3) vs. OR 1.7 (95% CI 0.5-5.5)]. The greater the number of these three types of inflammation documented, the higher the risk of VE (P<0.0001).

CONCLUSION

Chronic placental inflammation, acute fetal inflammation, and neonatal inflammation-initiating illness seem to interact in contributing risk information and/or directly damaging the developing brain of newborns delivered very preterm.

Estimating the nucleated red blood cell 'emergence time' in neonates

OBJECTIVE

The time between onset of fetal hypoxia and first appearance of nucleated red blood cells (NRBCs) in the blood can conceptually be divided into two periods; (1) the 'erythropoietin (EPO) generation time', which previous fetal studies suggest is 4 to 5 h, and (2) the 'NRBC emergence time'. In this study, we estimated the latter as the time required for NRBC to appear in the blood after administering a dose of recombinant EPO.

STUDY DESIGN

This was a retrospective analysis of data from a multihospital healthcare system (Intermountain Healthcare). Data were included only for neonates born ≥34 weeks gestation between the dates 1 January 2005 and 31 October 2012 and only if they received a dose of darbepoetin during their neonatal intensive care unit stay and had one or more complete blood cell counts (CBCs) obtained during the 3-day period before the dose was given and one or more CBCs in the 7-day period after the dose.

RESULT

The study involved 31 neonates who received 34 doses of darbepoetin. Seven doses were 4 μg kg(-1) and twenty-seven doses were 10 μg kg(-1). Twenty-six CBCs were obtained during the 24-h period following the darbepoetin dose and none had NRBC identified. NRBC first appeared in the blood between 24 and 36 h after the dose. Recipients of the higher dose generally had a higher peak NRBC count but the NRBC 'emergence time' did not appear to depend on dose.

CONCLUSION

Following fetal hypoxia, transcription and translation of the EPO gene result in an elevation in plasma EPO concentration. Previous fetal studies suggest this process requires 4 to 5 h. The present studies suggest that, following the increase in plasma EPO, NRBC emerge into the circulation in ≥24 h. If this model serves as a reasonable estimate, it suggests that neonates with an elevated NRBC count at birth had the onset of hypoxia at least 28 to 29 h before birth.

Association of nucleated red blood cells and severity of encephalopathy in normothermic and hypothermic infants

AIM

To determine whether hypothermia alters the discriminative ability of postnatal nucleated red blood cells (NRBCs) to distinguish between mild and moderate/severely encephalopathic infants.

METHODS

A prospective cohort study recruited full-term neonates with hypoxic ischaemic encephalopathy (HIE) from 2003 to 2012 (prehypothermic and hypothermic eras). The NRBC count was analysed in the first 24 h in all infants and compared between normothermic and hypothermic cohorts. The severity of encephalopathy was categorized using both clinical Sarnat score and continuous multichannel EEG.

RESULTS

Eighty-six infants with HIE were included: in the normothermic group, 19 were clinically mild, 24 moderate/severe; in the hypothermic group, 22 were mild, 21 moderate/severe encephalopathy. NRBC count discriminated between mild and moderate/severe Sarnat scores in the normothermic group (p = 0.03) but not in the hypothermic group (p = 0.9). This change was due to a decrease in NRBCs among moderately encephalopathic infants in the hypothermic cohort.

CONCLUSION

Postnatal NRBCs distinguished between mild and moderate/severe encephalopathy in normothermic infants but not in infants undergoing therapeutic hypothermia. We advise caution when using postnatal blood samples to study diagnostic biomarkers for HIE without first analysing the potential impact of hypothermia upon these markers.

Noninvasive prediction of intra-amniotic infection and/or inflammation in preterm premature rupture of membranes

OBJECTIVE

To develop a model based on noninvasive parameters to predict the probability of intra-amniotic infection and/or inflammation (IAI) in women with preterm premature rupture of membranes (PPROMs).

METHODS

Maternal blood was collected for determination of the C-reactive protein (CRP) level and white blood cell (WBC) count immediately after amniocentesis in 171 consecutive women with PPROMs. Intra-amniotic infection and/or inflammation was defined as a positive amniotic fluid (AF) culture and/or an elevated AF interleukin 6 level (≥2.6 ng/mL).

RESULTS

A risk score based on a model including maternal blood CRP, WBC, parity, and gestational age was calculated for each patient. The model was shown to have an adequate goodness of fit (P = .516), and the area under the receiver-operating characteristic curve was 0.848, indicating very good discrimination.

CONCLUSION

The noninvasive model based on maternal blood CRP, WBC, parity, and gestational age is highly predictive of IAI in women with PPROMs.

Hematologic profile of the fetus with systemic inflammatory response syndrome

OBJECTIVE

The fetal inflammatory response syndrome (FIRS) is associated with impending onset of preterm labor/delivery, microbial invasion of the amniotic cavity and increased perinatal morbidity. FIRS has been defined by an elevated fetal plasma interleukin (IL)-6, a cytokine with potent effects on the differentiation and proliferation of hematopoietic precursors. The objective of this study was to characterize the hematologic profile of fetuses with FIRS.

STUDY DESIGN

Fetal blood sampling was performed in patients with preterm prelabor rupture of membranes and preterm labor with intact membranes (n=152). A fetal plasma IL-6 concentration ≥ 11 pg/mL was used to define FIRS. Hemoglobin concentration, platelet count, total white blood cell (WBC) count, differential count, and nucleated red blood cell (NRBC) count were obtained. Since blood cell count varies with gestational age, the observed values were corrected for fetal age by calculating a ratio between the observed and expected mean value for gestational age.

RESULTS

1) The prevalence of FIRS was 28.9% (44/152); 2) fetuses with FIRS had a higher median corrected WBC and corrected neutrophil count than those without FIRS (WBC: median 1.4, range 0.3-5.6, vs. median 1.1, range 0.4-2.9, P=0.001; neutrophils: median 3.6, range 0.1-57.5, vs. median 1.8, range 0.2-13.9, P<0.001); 3) neutrophilia (defined as a neutrophil count >95th centile of gestational age) was significantly more common in fetuses with FIRS than in those without FIRS (71%, 30/42, vs. 35%, 37/105; P<0.001); 4) more than two-thirds of fetuses with FIRS had neutrophilia, whereas neutropenia was present in only 4.8% (2/42); 5) FIRS was not associated with detectable changes in hemoglobin concentration, platelet, lymphocyte, monocyte, basophil or eosinophil counts; and 6) fetuses with FIRS had a median corrected NRBC count higher than those without FIRS. However, the difference did not reach statistical significance (NRBC median 0.07, range 0-1.3, vs. median 0.04, range 0-2.3, P=0.06).

CONCLUSION

The hematologic profile of the human fetus with FIRS is characterized by significant changes in the total WBC and neutrophil counts. The NRBC count in fetuses with FIRS tends to be higher than fetuses without FIRS.

Maternal snoring during pregnancy is associated with enhanced fetal erythropoiesis--a preliminary study

OBJECTIVE AND BACKGROUND

Snoring is common among pregnant women and early reports suggest that it may bear a risk to the fetus. Increased fetal erythropoiesis manifested by elevated circulating nucleated red blood cells (nRBCs) has been found in complicated pregnancies involving fetal hypoxia. Both erythropoietin (EPO) and interleukin-6 (IL-6) mediate elevation of circulating nRBCs. The intermittent hypoxia and systemic inflammation elicited by sleep-disordered breathing (SDB) could affect fetal erythropoiesis during pregnancy. We hypothesized that maternal snoring will result in increased levels of fetal circulating nRBCs via increased concentrations of EPO, IL-6, or both.

METHODS

Women of singleton uncomplicated full-term pregnancies were recruited during labor and completed a designated questionnaire. Umbilical cord blood was collected immediately after birth and analyzed for nRBCs, plasma EPO and plasma IL-6 concentrations. Newborn data were retrieved from medical records.

RESULTS

One hundred and twenty-two women were recruited. Thirty-nine percent of women reported habitual snoring during pregnancy. Cord blood levels of circulating nRBCs, EPO and IL-6 were significantly elevated in habitual snorers compared with non-snorers (p = 0.03, 0.005 and 0.01; respectively). No differences in maternal characteristics or newborn crude outcomes were found.

CONCLUSIONS

Maternal snoring during pregnancy is associated with enhanced fetal erythropoiesis manifested by increased cord blood levels of nRBCs, EPO and IL-6. This provides preliminary evidence that maternal snoring is associated with subtle alterations in markers of fetal well being.

A study on the measurement of the nucleated red blood cell (nRBC) count based on birth weight and its correlation with perinatal prognosis in infants with very low birth weights

Purpose

The aim of this study was conducted to investigate the mean nRBC count in very low births weight infants (VLBWIs) and to determine the usefulness of the nRBC as an independent prognostic factors of perinatal complications in VLBWIs.

Methods

This study was conducted on 112 VLBWIs who were hospitalized in the neonatal intensive care unit (NICU) of the author's hospital within the period from March 2003 to and May 2008. Based on the infants' nucleated red blood cells (nRBC) counts at birth, on the third day after birth, on the seventh day after birth, in the second week after birth, and in the fourth week after birth in the medical records, the correlation between nRBC or absolute nRBC counts with birth weight, gestational age, and other perinatal outcomes were retrospectively investigated.

Results

In VLBWIs, their mean nRBC and absolute nRBC counts were showing a gradual decrease after birth, and they were consisteantly kept at low values since one week after and inversely proportional to the birth weights. The mean nRBC counts based on the stage after birth showed a significant correlation with perinatal death, necrotizing enterocolitis, and severe intraventricular hemorrhage.

Conclusion

The increase in the nRBC count showed a significant correlation with having a severe intraventricular hemorrhage, necrotizing enterocolitis, and perinatal death in VLBWIs. If an increase or no decrease in the nRBC count after birth is observed, newborn-infant care precautions should be required.

Cord blood erythropoietin and interleukin-6 for prediction of intraventricular hemorrhage in the preterm neonate

OBJECTIVE

To evaluate cord blood erythropoietin (EPO) and interleukin-6 (IL-6) levels to predict preterm infants at risk of developing intraventricular hemorrhage (IVH).

METHODS

Levels of umbilical cord EPO, acid-base status and IL-6 were analyzed in 116 consecutive, preterm newborns (GA at delivery: 29 [23-34 ] weeks) born to mothers who had a clinically indicated amniocentesis to rule out infection. Early-onset neonatal sepsis (EONS) was diagnosed using symptoms, hematological criteria and blood cultures.

RESULTS

IVH was diagnosed by cranial ultrasounds. The prevalence of IVH in our population was 25% (29/116). There was a direct relationship between cord blood EPO and cord blood IL-6 concentration (r = 0.225, p = 0.014), independent of GA at birth. Elevated cord blood EPO levels (r = 0.182, p = 0.016) and GA at birth (r =  -0.236, p = 0.004) remained significant independent factors associated with the risk of IVH, when evaluated with stepwise logistic regression analyses. Cord blood IL-6, pH, and EONS were not associated with IVH. These relationships remained following correction for GA at birth (p = 0.027).

CONCLUSIONS

Our results suggest that elevation in cord blood EPO may predict newborns at risk for IVH, independent of fetal inflammatory status. Further studies are warranted to confirm this association.

Response of leukocytes and nucleated red blood cells in very low-birth weight preterm infants after exposure to intrauterine inflammation

OBJECTIVES

To test the hypothesis if very immature preterm infants exposed to chorioamnionitis would exhibit increased numbers of leukocytes, neutrophils, and nucleated red blood cells (NRBC) in peripheral blood.

STUDY DESIGN

Preterm infants with birth weight <1500 g were prospectively evaluated. Blood cells were counted within the first hour of life in infants exposed to histological chorioamnionitis and controls.

RESULTS

Birth weight, gestational age, and sex did not differ between the groups (n = 71). Seventeen infants who were exposed to chorioamnionitis had significantly higher counts of leukocytes, neutrophils, and immature neutrophils after birth. However, there was no difference in the number of circulating NRBCs between both groups. In contrast, there was a tendency towards an increased NRBC count in the control group.

CONCLUSION

Preterm infants exposed to chorioamnionitis elicited a strong inflammatory response as reflected by increased numbers of leukocytes and neutrophils. However, chorioamnionitis did not induce an increase in numbers of NRBC.

Inflammation-induced preterm birth in a murine model is associated with increases in fetal macrophages and circulating erythroid precursors

The presence of intrauterine inflammation has been associated with adverse neurologic outcomes in preterm infants, but the precise mechanisms of fetal brain injury remain unclear. We sought to evaluate inflammatory cell trafficking, fetal organ damage, and molecular regulation in the fetoplacental unit using an established mouse model of preterm birth associated with intrauterine inflammation. Gestational sacs were harvested 6 hours after intrauterine infusion of saline or lipopolysaccharide (LPS). Histologic, immunohistochemical, and molecular investigations were performed to identify target organ damage and the cellular phenotype of inflammatory cells and to quantify circulating inflammatory and hematopoietic mediators within the placental and fetal tissue. There was widespread increase in fetal macrophages in LPS-exposed pups, including within the leptomeninges of the brain, associated with significantly higher of interleukin 6 levels in LPS-exposed pups. Although no specific central nervous system injury (necrosis or apoptosis) was documented, liver hematomas were seen significantly more frequently in LPS-exposed pups. Circulating nucleated fetal erythrocytes were also present more frequently with LPS exposure without significantly higher erythropoietin levels than saline-exposed mice. The presence of increased macrophages, increased circulating interleukin 6 levels, and increased circulating erythroid precursors in LPS-exposed pups suggests that these are significant factors associated with potential target organ damage, such as liver hematomas, associated with intrauterine inflammation and preterm birth. The role of macrophages within the fetal leptomeninges is unclear, but they may play an important role in inflammatory-mediated brain damage, and further investigation of their significance and potential as therapeutic targets is warranted.

Characterization of RAGE, HMGB1, and S100beta in inflammation-induced preterm birth and fetal tissue injury

Immune activation represents an adaptive reaction triggered by both noxious exogenous (microbes) and endogenous [high mobility group box-1 protein (HMGB1), S100 calcium binding proteins] inducers of inflammation. Cell stress or necrosis lead the release of HMGB1 and S100 proteins in the extracellular compartment where they act as damage-associated molecular pattern molecules (or alarmins) by engaging the receptor for advanced glycation end-products (RAGE). Although the biology of RAGE is dictated by the accumulation of damage-associated molecular pattern molecules at sites of tissue injury, the role of RAGE in mediating antenatal fetal injury remains unknown. First, we studied the relationships at birth between the intensity of human fetal inflammation and sRAGE (an endogenous RAGE antagonist), HMGB1, and S100beta protein. We found significantly lower sRAGE in human fetuses that mounted robust inflammatory responses. HMGB1 levels correlated significantly with levels of interleukin-6 and S100beta in fetal circulation. We then evaluated the levels and areas of tissue expression of RAGE, HMGB1, and S100beta in specific organs of mouse fetuses on E16. Using an animal model of endotoxin-induced fetal damage and preterm birth, we determined that inflammation induces a significant change in expression of RAGE and HMGB1, but not S100beta, at sites of tissue damage. Our findings indicate that RAGE and HMGB1 may be important mediators of cellular injury in fetuses delivered in the setting of inflammation-induced preterm birth.

Using proteomics in perinatal and neonatal sepsis: hopes and challenges for the future

PURPOSE OF REVIEW

Particularities of the fetal immune response to infection cause a heightened inflammatory state that acts synergistically with microbial insult to induce damage. Proteomics offers the opportunity for detecting fetuses at risk of sepsis and neurological injury.

RECENT FINDINGS

Molecular tools (16S-rRNA) demonstrate that the diversity of microbial agents of intra-amniotic infection exceeds what is suspected clinically or is documented by cultures. The resulting inflammatory process has the potential to damage the fetus in utero. Stepwise algorithms (mass restricted score) have been developed to extract proteomic profiles characteristic of amniotic fluid inflammation. The mass restricted score includes four proteomic biomarkers: defensin-2, defensin-1, S100A12, and S100A8 proteins. Other amniotic fluid biomarkers relevant for preterm birth are S100A9 and insulin-like growth factor-binding protein 1. S100A12 - ligand for the receptor of advanced glycation end products - has the strongest association with histological chorioamnionitis and funisitis. Presence of S100A12 and S100A8 in amniotic fluid is predictive of early-onset neonatal sepsis and poor neurodevelopmental outcome.

SUMMARY

Presence of amniotic fluid proteomic biomarkers of inflammation is associated with increased inflammatory status of the fetus at birth. Future challenges are to find biomarkers that provide insight into molecular mechanisms of chronic fetal and neonatal cellular damage and to identify candidates for early neuroprotection strategies.

Fetal renal artery impedance as assessed by Doppler ultrasound in pregnancies complicated by intraamniotic inflammation and preterm birth

OBJECTIVE

The objective of the study was to evaluate the fetal renal artery impedance in the context of inflammation-associated preterm birth.

STUDY DESIGN

We conducted a prospective Doppler assessment of the fetal renal artery impedance in 70 singleton fetuses. The study group consisted of 56 premature fetuses (median, 28.1 [interquartile range, 25.3-30.6] weeks at enrollment). Gestational age (GA) reference ranges were generated based on fetuses with uncomplicated pregnancies (n = 14). Doppler studies included renal artery pulsatility index (PI), resistance index (RI), systolic/diastolic (S/D) ratio, and presence or absence of end-diastolic blood flow. Proteomic profiling (surface-enhanced laser desorption ionization time-of-flight) was used for assessment of intraamniotic inflammation and biomarker peak corresponding to beta2-microglubin. Data were interpreted in relationship to amniotic fluid index (AFI), cord blood interleukin (IL)-6 and erythropoietin (EPO) levels. The cardiovascular and metabolic profiles of the neonates were investigated in the first 24 hours of life.

RESULTS

Fetuses delivered by mothers with intraamniotic inflammation had higher cord blood IL-6 but not EPO levels. Fetal inflammation did not affect either renal artery PI, RI, S/D ratio, or end-diastolic blood flow. Neonates delivered in the context of intraamniotic inflammation had higher serum blood urea nitrogen levels, which correlated significantly with AF IL-6 levels. The renal artery RI and SD ratio were inversely correlated with the AFI independent of GA, cord blood IL-6, and status of the membranes.

CONCLUSION

The fetus is capable of sustaining normal renal artery impedance despite inflammation. Resistance in the renal vascular bed affects urine output independent of inflammation.