A Comprehensive Approach to Neonatal Peripheral Blood Findings of Preterm and Full-term Infants: an Updated Review

BACKGROUND

Peripheral blood film morphology in neonates is significantly different from the adults as neonatal erythrocytes show a marked heterogeneity. Moreover, there seem to be a more significant numbers of irregular shaped red blood cells such as stomatocytes, keratocytes, schistocytes, and acantocytes in newborns, particularly in preterm infants. This review study focused on the red blood cell morphology in term and preterm neonates to detect clues to distinguish between the peripheral blood film of newborns under physiological and pathological conditions.

METHODS

The peripheral blood findings and blood cell counts in preterm and term neonates were studied and compared to each other using available scientific databases and indexing systems such as PubMed and Google Scholar.

RESULTS

This approach is a simple, cost-effective, quick, and informative method to distinguish between physiological and pathological conditions in neonates and detect hematological disorders.

CONCLUSIONS

Peripheral blood film plays a crucial role in diagnosing anemia and blood-related diseases, determining the type of anemia, and identifying specific morphological abnormalities of red cell membrane disorders.

Frequency of red blood cell transfusions in preterm neonates in Brazil: A systematic review and meta-analysis

BACKGROUND AND OBJECTIVES

Red blood cell transfusions are frequent in preterm neonates. The proportion of preterm neonates transfused in Brazil remains unknown. We systematically reviewed the literature to estimate the frequency of red blood cell transfusions in preterm neonates in Brazil.

MATERIALS AND METHODS

The LILACS, EMBASE, Cochrane, SciELO, MEDLINE (PubMed), Web of Science, Scopus, BDTD and 27 national university institutional databases were searched for studies that analysed red blood cell transfusion in preterm neonates in Brazil without period restriction. The Preferred Reporting Items in Systematic Reviews and Meta-Analyses guidelines were followed, and the GRADE methodology was applied. A random-effects model along with the restricted maximum likelihood method was used, and the Freeman-Tukey transformed proportion was used to estimate effect size.

RESULTS

Nine studies, representing 6548 preterm neonates, were included in the qualitative and quantitative analyses. The mean gestational age ranged from 26.0 to 31.6 weeks. Most of the studies were from the Southeast region. The pooled estimated frequency of red blood cell transfusions was 58.0% (95% confidence interval = 52.0%-64.0%, p < 0.001) with low certainty. There was statistically significant heterogeneity among studies (I2  = 92.5%, p < 0.001).

CONCLUSION

In this current meta-analysis of the evidence available, which included moderate and extremely preterm neonates, the observed frequency of red blood cell transfusions in preterm neonates in Brazil was 58.0% and this estimate can help health programming. Some Brazilian regions were not included in this study, and further research is needed to provide a more representative overview of Brazil.

Blood Donor Sex and Outcomes in Transfused Infants

Red blood cell transfusion is common in neonatal intensive care. Multiple trials have evaluated different thresholds for when to administer red blood cell transfusion. In contrast, there has been less focus on studies of the characteristics of red blood cells transfused into neonates. In this review, the authors summarize the emerging literature on the potential impact of the sex of blood donors on outcomes in transfused neonates using a systematic search strategy. The authors review the uncertainty generated from studies with conflicting findings and discuss considerations regarding the impact of blood donor sex and other characteristics on neonatal outcomes.

Anemia, Iron Supplementation, and the Brain

The developing brain is particularly vulnerable to extrinsic environmental events such as anemia and iron deficiency during periods of rapid development. Studies of infants with postnatal iron deficiency and iron deficiency anemia clearly demonstrated negative effects on short-term and long-term brain development and function. Randomized interventional trials studied erythropoiesis-stimulating agents and hemoglobin-based red blood cell transfusion thresholds to determine how they affect preterm infant neurodevelopment. Studies of red blood cell transfusion components are limited in preterm neonates. A biomarker strategy measuring brain iron status and health in the preanemic period is desirable to evaluate treatment options and brain response.

Associations of High-Sensitive Cardiac Troponin T in Healthy Newborns and Prolonged Second Stage of Labor, Neonatal and Maternal Factors: A Prospective Study

INTRODUCTION

High-sensitivity cardiac troponin T (hs-cTnT) is not used routinely as a diagnostic biomarker in newborns. The high precision of hs-cTnT assays increases the ability to determine small differences in cTnT over time and to detect troponin T elevation; thus, we believe that hs-cTnT assays might improve clinical care. We explored the plausible association between hs-cTnT levels (ng/L) in healthy newborns and prolonged second stage of labor, neonatal, and maternal factors.

METHODS

A prospective study was performed among healthy newborns in the Obstetrics and Gynecology Department at Hillel Yaffe Medical Center in Israel in January-June 2021. The sociodemographic characteristics of the participants, maternal age, gravidity, parity, Pitocin use, epidural analgesia, and neonatal anemia were obtained from the electronic medical records. Gestational age was determined by ultrasound biometric measurements. We classified second-stage labor as normal or prolonged using the WHO guidelines. Samples from umbilical cord blood were drawn using syringes rinsed with anticoagulant by a specialist in pediatrics. The remaining blood was used to determine hs-cTnT levels (ng/L), which was defined as a continuous quantitative variable with the median value and the 25th-75th percentiles.

RESULTS

Overall, 184 cord blood samples were performed from healthy newborns (60.6% males) with a median hs-cTnT of 39.03 (25th-75th percentiles = 30.53-54.09) ng/L. A multivariable linear regression model showed no significant association between neonatal anemia and hs-cTnT levels (ng/L) (p = 0.8). Gestational age (B coefficient -4.24, p < 0.001) and gravidity (B coefficient -2.41, p = 0.03) were negatively associated with hs-cTnT levels (ng/L), while Pitocin use (B coefficient 6.91, p = 0.04) and prolonged second stage of labor (B coefficient 18.07, p = 0.02) were positively associated with hs-cTnT levels (ng/L).

CONCLUSIONS

High hs-cTnT levels (ng/L) were documented in the cord blood of healthy newborns. Hs-cTnT levels were positively correlated with a prolonged second stage of labor and Pitocin use and negatively correlated with longer gestational age and higher gravidity. Hs-cTnT may signify labor-related fetal distress. A larger surveillance study is mandatory to establish this correlation and assess for possible prognostic significance of elevated hs-cTnT in this context.

Risk factors for anemia of prematurity among 30-35-week preterm infants

BACKGROUND

The risk factors for anemia of prematurity (AOP) among late preterm infants are unelucidated. We identified risk factors for declining hemoglobin (Hb) concentration and triggering factors for AOP treatment in infants born at 30-35 gestational weeks.

METHODS

From 2012 to 2020, we conducted a single-center retrospective study of infants born at 30-35 weeks of gestation without congenital anomalies or severe hemorrhage. The primary outcome was AOP development, defined by initiation of treatments including red blood cell transfusion, subcutaneous injections of erythropoietin, and iron supplementation. A multivariable logistic regression model was used to investigate potential risk factors for AOP.

RESULTS

A total of 358 infants were included. Lower gestational age (odds ratio, 0.19; 95% confidence interval 0.11-0.32), small for gestational age (SGA; 7.17, 2.15-23.9), low maternal Hb level before birth (0.66, 0.49-0.87), low Hb at birth (0.71, 0.57-0.89), and multiple large blood samplings (1.79; 1.40-2.29) showed significantly higher odds for AOP development.

CONCLUSIONS

Gestational age, SGA, low maternal Hb before birth, Hb at birth, and high number of large blood samplings were positively associated with AOP development in infants born at 30-35 gestational weeks.

Effect of Early Erythropoietin on Retinopathy of Prematurity: A Stratified Meta-Analysis

BACKGROUND

Recombinant human erythropoietin (rhEPO) lost its role in minimizing red blood cell transfusion in very preterm infants after it had been associated with severe retinopathy of prematurity (ROP). Previous systematic reviews did not stratify ROP by gestation and birth weight (BW).

OBJECTIVES

The aim of this study was to investigate the effect of early prophylactic rhEPO on ROP in a stratified meta-analysis of randomized controlled trials (RCTs).

METHODS

The databases EMBASE, MEDLINE, and the Cochrane Central Register of Controlled Trials were searched in January 2022 and complemented by citation searching. RCTs comparing early rhEPO treatment with no treatment or placebo were selected if they were published in a peer-reviewed journal and reported ROP outcomes. Previously unpublished data were requested from the study authors to allow stratified analyses by gestational age (GA) and BW. Data were extracted and analyzed using the standard methods of the Cochrane Neonatal Review Group. Pre-specified outcomes were "ROP stage ≥3" (primary outcome) and "any ROP."

RESULTS

Fourteen RCTs, comprising 2,040 infants of <29 weeks of GA, were included for meta-analysis. Data syntheses showed no effects of rhEPO on ROP stage ≥3 or on any ROP, neither in infants of <29 weeks GA, nor in infants of <1,000 g BW, nor in any GA strata. The risk ratio (95% confidence interval) for ROP stage ≥3 in infants of <29 weeks of GA was 1.13 (0.84, 1.53), p = 0.41 (quality of evidence: moderate).

CONCLUSIONS

The present meta-analysis detected no effects of early rhEPO on ROP in any comparison, but most stratified analyses were limited by low statistical power.

Immunologic effects of red blood cell and platelet transfusions in neonates

PURPOSE OF REVIEW

Premature neonates are frequently transfused red blood cells (RBCs) or platelets to raise hemoglobin or platelet counts. However, these transfusions may have unintended effects on the immune system. This review will summarize the newest discoveries on the immunologic effects of RBC and platelet transfusions in neonates, and their potential impact on neonatal outcomes.

RECENT FINDINGS

Neonatal RBC transfusions are associated with increases in plasma pro-inflammatory cytokines, but recent findings suggest sex-specific differential responses. At least one cytokine (monocyte chemoattractant protein-1) rises in females receiving RBC transfusions, but not in males. These inflammatory responses correlate with poorer neurodevelopmental outcomes in heavily transfused female infants, while preterm male infants seem to be more sensitive to severe anemia. Platelet transfusions in preterm neonates are associated with increased neonatal mortality and morbidity. The underlying mechanisms are unknown, but likely related to the immune/inflammatory effects of transfused platelets. Adult platelets are different from neonatal platelets, with the potential to be more pro-inflammatory. Early preclinical data suggest that platelet transfusions alter the neonatal systemic inflammatory response and enhance immune cell migration.

SUMMARY

RBC and platelet transfusions alter neonatal immune and inflammatory responses. Their pro-inflammatory effects might worsen neonatal disease or affect neurodevelopmental outcomes.

Red blood cell transfusions in preterm newborns and neurodevelopmental outcomes at 2 and 5 years of age

BACKGROUND

Red blood cell (RBC) transfusion is often considered a life-saving measure in preterm neonates. However, it has been associated with detrimental effects on short-term morbidities and, recently, on brain development. The aim of the present study was to evaluate the association between RBC and long-term neurodevelopmental outcome in a cohort of preterm infants.

MATERIALS AND METHODS

This retrospective cohort study was carried out in the period 2007-2013. Preterm infants with a gestational age (GA) ≤ 32 weeks and birthweight (BW) <1,500 g were included. Infants underwent Griffiths assessment at 24±6 months corrected age (CA) and at 5±1 years of age. We used a multivariate regression model to assess the association of RBC transfusions and long-term neurodevelopment after controlling for GA, being small for GA, major neonatal morbidities, and socio-economic status. We also evaluated the impact of early RBC administration (within the first 28 days of life) compared to those performed after the first month of life.

RESULTS

We enrolled 644 preterm infants, among whom 54.3% were transfused during their stay in the neonatal intensive care unit (NICU). In infants with a longitudinal follow-up evaluation (n=360), each RBC transfusion was independently associated with a reduction in the Griffiths General Quotient (GQ) by -0.96 (p=0.002) at 24 months CA. Early RBC administration had the biggest impact, especially in children without brain lesions, where the reduction in Griffiths GQ for each additional transfusion was -2.12 (p=0.001) at 24 months CA and -1.31 (p=0.006) at 5 years of age, respectively.

DISCUSSION

In preterm infants, RBC transfusions are associated with long-term neurodevelopmental outcome, with a cumulative effect. Early RBC administration is associated with a greater reduction in Griffiths scores. The impact of RBC transfusion on neurodevelopment is greater at 24 months CA, but persists, although to a lesser degree, at 5 years of age.

Severe Neonatal Anemia Due to Spontaneous Massive Fetomaternal Hemorrhage at Term: An Illustrative Case with Suspected Antenatal Diagnosis and Brief Review of Current Knowledge

Fetomaternal hemorrhage is defined as transfer of fetal blood into placental circulation and therefore into maternal circulation during pregnancy, and represents an important contributor to intrauterine fetal demise and neonatal death. The condition is rarely diagnosed prenatally because clinical findings are often nonspecific, and it is unpredictable. In this paper we present an illustrative case of massive spontaneous fetomaternal hemorrhage where the diagnosis was highly suspected antenatally based on maternal reported reduced fetal movements, abnormal suggestive cardiotocographic trace, and increased peak systolic velocity in the fetal middle cerebral artery. We discuss obstetrical and neonatal management and review the current knowledge in the literature. Maintaining a high index of suspicion for this condition allows the obstetrician to plan for adequate diagnostic tests, arrange intrauterine treatment or delivery, and prepare the neonatal team.

Associations between Parity, Hair Hormone Profiles during Pregnancy and Lactation, and Infant Development in Rhesus Monkeys (Macaca mulatta)

Studies examining hormones throughout pregnancy and lactation in women have been limited to single, or a few repeated, short-term measures of endocrine activity. Furthermore, potential differences in chronic hormonal changes across pregnancy/lactation between first-time and experienced mothers are not well understood, especially as they relate to infant development. Hormone concentrations in hair provide long-term assessments of hormone production, and studying these measures in non-human primates allows for repeated sampling under controlled conditions that are difficult to achieve in humans. We studied hormonal profiles in the hair of 26 female rhesus monkeys (Macaca mulatta, n=12 primiparous), to determine the influences of parity on chronic levels of cortisol (hair cortisol concentration, HCC) and progesterone (hair progesterone concentration, HPC) during early- to mid-pregnancy (PREG1), in late pregnancy/early lactation (PREG2/LACT1), and in peak lactation (LACT2). We also assessed infants' neurobehavioral development across the first month of life. After controlling for age and stage of pregnancy at the first hair sampling period, we found that HCCs overall peaked in PREG2/LACT1 (p=0.02), but only in primiparous monkeys (p<0.001). HPCs declined across pregnancy and lactation for all monkeys (p<0.01), and primiparous monkeys had higher HPCs overall than multiparous monkeys (p=0.02). Infants of primiparous mothers had lower sensorimotor reflex scores (p=0.02) and tended to be more irritable (p=0.05) and less consolable (p=0.08) in the first month of life. Moreover, across all subjects, HCCs in PREG2/LACT1 were positively correlated with irritability (r(s)=0.43, p=0.03) and negatively correlated with sensorimotor scores (r(s)=-0.41, p=0.04). Together, the present results indicate that primiparity influences both chronic maternal hormonal profiles and infant development. These effects may, in part, reflect differential reproductive and maternal effort in mothers with varied caretaking experience. In addition, infant exposure to relatively higher levels of maternal cortisol during the late fetal and early postnatal periods is predictive of poorer developmental outcomes.

Prevalence of Rh negative pregnant women who attended the antenatal clinic and delivered in Rajavithi Hospital: 2000-2005

OBJECTIVE

To assess the prevalence of Rh-negative pregnant women who attended the antenatal clinic and delivered in Rajavithi Hospital.

MATERIAL AND METHOD

A descriptive retrospective study in Rh-negative pregnant women was done. The present study included the general characteristic of cases, anti-D immunoglobulin prophylaxis administration, fetal anemia and neonatal jaundice.

RESULTS

During the study period, 147 Rh-negative pregnant women delivered at Rajavithi Hospital. The prevalence of Rh-negative pregnant women in Rajavithi hospital was 0.31%. Fetal anemia and neonatal jaundice were detected in 21.9% and 37.2%, respectively, and 68.14% of cases received antenatal anti-D immunoglobulin. Anti-D immunoglobulin prophylaxis significantly reduced the incidence of neonatal jaundice (p < 0.05).

CONCLUSION

The prevalence of Rh-negative pregnant women was 0.31%.

Nutritional anemias in infancy

Anemia in the 1st year of life should be an important warning sign to the clinician of a potential underlying nutritional deficiency. Prompt diagnosis and treatment are warranted in many cases, not only to treat the anemia but also, more important, to prevent other long-term sequelae associated with the underlying, causative deficiency. As more information about the impact of nutrition on various aspects of health is collected and newer therapies for the treatment of disease are developed, it will be important to understand and consider the role of vitamins and minerals in a light beyond the realm of nutritional anemia.