Is there a role for erythropoietin in neonatal medicine?

Blood transfusion for anaemia of prematurity: Current practice in Australia and New Zealand

AIM

To characterise the current transfusion practice among clinicians in Australasian neonatal units and factors that influence their decision-making.

METHODS

Members of the Australia and New Zealand Neonatal Network (ANZNN) and practitioners at their local institutions were invited to participate in a 15-question web-based survey between 1 June and 31 July 2016. The survey was designed to assess (i) haemoglobin-based transfusion thresholds; (ii) presence of local guidelines; (iii) preference for a restrictive or liberal transfusion policy; (iv) perceived benefits and risks of transfusion; and (v) use of clinical adjuncts to assist decision-making.

RESULTS

Overall, 130 participants responded to at least one question. Haemoglobin transfusion thresholds for anaemia of prematurity (AOP) varied significantly from <60 to <120 g/L. Of 103 participants, 36 (35%) reported that they do not have access to local transfusion guidelines. The majority utilise multiple clinical and haematological parameters to guide their decision-making, and approximately half (45/84, 54%) believe that tissue hypoxia detected by near-infrared spectroscopy (NIRS) may better inform transfusion thresholds. Of 102 participants, 51 (50%) support a restrictive rather than liberal transfusion policy. The most commonly reported perceived risks of transfusion for AOP were suppression of endogenous erythropoiesis and increased rates of necrotising enterocolitis.

CONCLUSIONS

There is a significant variation in transfusion practice in Australasian neonatal units. Quality and safety initiatives may assist with improved consistency of transfusion practice across the ANZNN. However, further research is required to better define optimal transfusion thresholds, quantify potential risks of transfusion and determine clinical utility of newer adjuncts such as NIRS.

Protective Activity of Erythropoyetine in the Cognition of Patients with Parkinson's Disease

Introduction: Treatment strategies in Parkinson’s disease (PD) can improve a patient’s quality of life but cannot stop the progression of PD. We are looking for different alternatives that modify the natural course of the disease and recent research has demonstrated the neuroprotective properties of erythropoietin. In Cuba, the Center for Molecular Immunology (CIM) is a cutting edge scientific center where the recombinant form (EPOrh) and recombinant human erythropoietin with low sialic acid (NeuroEPO) are produced. We performed two clinical trials to evaluate the safety and tolerability of these two drugs in PD patients. In this paper we want to show the positive results of the additional cognitive tests employed, as part of the comprehensive assessment. Materials and method: Two studies were conducted in PD patients from the outpatient clinic of CIREN, including n = 10 and n = 26 patients between 60 and 66 years of age, in stages 1 to 2 of the Hoehn and Yahr Scale. The first study employed recombinant human (rhEPO) and the second an intranasal formulation of neuroEPO. All patients were evaluated with a battery of neuropsychological scales composed to evaluate global cognitive functioning, executive function, and memory. Results: The general results in both studies showed a positive response to the cognitive functions in PD patients, who were undergoing pharmacological treatment with respect to the evaluation (p < 0.05) before the intervention. Conclusions: Erythropoietin has a discrete positive effect on the cognitive functions of patients with Parkinson’s disease, which could be interpreted as an effect of the neuroprotective properties of this molecules. To confirm the results another clinical trial phase III with neuroEPO is in progress, also designed to discard any influence of a placebo effect on cognition.

Haemolytic disease of the fetus and newborn

Haemolytic Disease of the Fetus and Newborn (HDFN) is caused by maternal alloimmunization against red blood cell antigens. In severe cases, HDFN may lead to fetal anaemia with a risk for fetal death and to severe forms of neonatal hyperbilirubinaemia with a risk for kernicterus. Most severe cases are caused by anti-D, despite the introduction of antental and postnatal anti-D immunoglobulin prophylaxis. In general, red blood cell antibody screening programmes are aimed to detect maternal alloimmunization early in pregnancy to facilitate the identification of high-risk cases to timely start antenatal and postnatal treatment. In this review, an overview of the clinical relevance of red cell alloantibodies in relation to occurrence of HDFN and recent views on prevention, screening and treatment options of HDFN are provided.

Population pharmacodynamic analysis of erythropoiesis in preterm infants for determining the anemia treatment potential of erythropoietin

A population pharmacokinetics/pharmacodynamic (PK/PD) model was developed to describe changes in erythropoiesis as a function of plasma erythropoietin (EPO) concentration over the first 30 days of life in preterm infants who developed severe anemia requiring red blood cell (RBC) transfusion. Several covariates were tested as possible factors influencing the responsiveness to EPO. Discarded blood samples in 27 ventilated preterm infants born at 24-29 wk of gestation were used to construct plasma EPO, hemoglobin (Hb), and RBC concentration-time profiles. The amount of Hb removed for laboratory testing and that transfused throughout the study period were recorded. A population PK/PD model accounting for the dynamic Hb changes experienced by these infants was simultaneously fitted to plasma EPO, Hb, and RBC concentrations. A covariate analysis suggested that the erythropoietic efficacy of EPO is increased for preterm infants at later gestational ages. The PD analysis showed a sevenfold difference in maximum Hb production rate dependent on gestational age and indicated that preterm infants, when stimulated by EPO, have the capacity to produce additional Hb that may result in a decrease in RBC transfusions. The present model has utility in clinical trial simulations investigating the treatment potential of erythropoietic stimulating agents in the treatment of anemia of prematurity.

Necrotizing enterocolitis and the role of anemia of prematurity

Necrotizing enterocolitis (NEC) is one of the most common surgical diseases of preterm infants, with significant short- and long-term morbidity and mortality. Although the etiology of NEC remains elusive, multiple factors adversely affecting the intestinal mucosal integrity of preterm infants are known to be associated with NEC. Anemia and red blood cell (RBC) transfusion-related gut injury have been shown to have strong correlation with NEC. Anemia potentially compromises mucosal integrity with subsequent poor healing, and this injury may be augmented by yet unknown factors associated with RBC transfusions. Although convincing evidence is lacking, there is a need for guidelines to keep the hematocrit within clinically and physiologically relevant limits by appropriate interventions. Further investigations need to focus on assessing the interplay between anemia, chronically hypoxemic/hypoperfused intestines, and early iron therapy or other pharmacologic approaches for prevention/treatment of anemia and RBC transfusions.

Serum prohepcidin concentrations at birth and 1 month after birth in premature infants

BACKGROUND

Premature newborns are vulnerable to iron imbalance, although the iron homeostasis during the perinatal period remains unclear. To clarify the iron metabolism of premature infants, we measured serum prohepcidin concentrations of preterm infants, and analyzed the association with iron parameters.

METHODS

Seventy-one (61 preterm and 10 term) infants were enrolled for the study, that had no underlying diseases including asphyxia, bleedings, infection, and anomalies. Serum concentrations of prohepcidin at birth and 1 month after birth were determined by enzyme-linked immunosorbent assay.

RESULTS

Prohepcidin levels at birth but not 1 month postnatal age positively correlated with gestational age (correlation coefficient [CC]:0.334, P = 0.005) and birth weight (CC: 0.367, P = 0.002). The levels at birth of preterm infants (median: 29.93 ng/ml, range: 4.0-110.6) were lower than those of full-term infants, and increased thereafter. On the other hand, the levels in small-for-gestational age infants were not associated with gestational age or birth weight. Prohepcidin levels at birth correlated positively with red cell counts (CC = 0.487, P = 0.025), unsaturated iron binding capacity (CC = 0.755, P = 0.001), total protein (CC = 0.624, P = 0.005), and serum albumin levels (CC = 0.500, P = 0.025), and negatively with serum iron levels (CC = -0.688, P = 0.003), but not ferritin levels. Multivariate analyses indicated that prohepcidin levels at birth were lower in infants with pregnancy-induced hypertension (P = 0.03) or premature rupture of membrane (P = 0.01).

CONCLUSIONS

Prohepcidin production was physiologically low at birth of preterm infants according to the gestational age, and the levels might be susceptible to the in utero stress. The postnatal increase might reflect the maturation and/or adaptation of iron homeostasis.

[Risk factors involved in the need for blood transfusion in very low birth weight newborns treated with erythropoietin]

OBJECTIVE

To identify and quantify risk factors related to red blood cell transfusion in premature babies weighing<1,500g who received erythropoietin (EPO). Secondly, to assess the relationship between retinopathy of prematurity and rh-EPO.

MATERIAL AND METHODS

Prospective descriptive study of infants admitted to the Reina Sofía University Hospital between January 2006 and March 2009. Infants reviewed had a birth weight<1,500g and gestational age<32 weeks. Infants were administered rh-EPO 750IU/kg/week subcutaneously 3 days/week/ 6 weeks. We used univariate and multivariate logistic regressions with PASW Statistics 18 for Windows.

RESULTS

Data were obtained from 110 infants, with a mean birth weight of 1154grs and mean gestational age of 29.3 weeks. Risk factors (OR; 95% CI) for being transfused were: male sex (4.41; 1.24-15.66), GA (1.64; 1.14-2.36, 1 week), Hb level on admission (1.45; 1.04-2.04; 1g/dl), late onset sepsis (7.75; 2.21-21.11), late onset treatment with rh-EPO (6.27; 1.22-32.35). All surgically treated infants with patent ductus arteriosus ligation or necrotizing enterocolitis needed transfusion. There is no relationship between rh-EPO administration and retinopathy of prematurity (ROP), but there was a relationship with transfusion.

CONCLUSIONS

Premature infants with the lower gestational age, being male, a lower Hb level on admission and late onset sepsis are those with the greatest risk for blood transfusion.

[Early administration of erythropoietin in the extreme premature, a risk factor for retinopathy of prematurity?]

INTRODUCTION

Erythropoietin (EPO) stimulates angiogenesis and may favour the appearance of retinopathy of prematurity (ROP). The objective was to determine if EPO+Fe administered from the 5th day of life could be an independent risk factor for ROP appearance and its severity.

PATIENTS AND METHOD

The study included 718 preterm newborns with a birth weight ≤1,500g or a gestational age ≤32 weeks (and 6 days), admitted between 2001 and 2008. During these years, the target SaO₂ was between 88% and 93%. EPO treatment began at 5-7 days of life, with a dose of 250 UI/Kg, 3 times a week, subcutaneously, together with Fe, 5-6mg/kg/day, both until 34 weeks of corrected age or discharge.

RESULTS

A total of 493 preterms (68.7%) did not have ROP, 139 (19.4%) had a grade 1 ROP, 50 (7.0%) a grade 2 ROP and 36 (5.0%) a grade 3 ROP. Laser therapy was required by 27 severe ROP was associated with lower birth weight and gestational age, more neonatal morbidity and a more aggressive treatment (duration of oxygen supplements or mechanical ventilation, number of blood transfusions). Risk factors independently and significantly associated with any ROP grade were: lower birth weight, no caesarean section, EPO administration and need for blood transfusion. EPO administration increased the risk of ROP by 2.4, but this only happened in case of grade 1 ROP (OR: 5.50).

CONCLUSIONS

EPO+Fe administration is associated and perhaps stimulates the appearance of grade 1 ROP.