Neonatal morbidity after exchange transfusion for red cell alloimmune hemolytic disease

Hemolytic disease of the fetus and newborn-a perspective of immunohematology

BACKGROUND

Hemolytic disease of the fetus and newborn is a public health problem caused by maternal-fetal incompatibility; no prophylaxis is available for most alloantibodies that induce this disease. This study reviews the literature regarding which antibodies are the most common in maternal plasma and which were involved in hemolytic disease of the fetus and newborn.

METHOD

Seventy-five studies were included in this review using a systematic search. Two independent authors identified studies of interest from the PubMed and SciELO databases.

MAIN RESULTS

Forty-four case reports were identified, of which 11 babies evolved to death. From 17 prevalence studies, the alloimmunization rate was 0.17 % with 161 babies receiving intrauterine transfusions and 23 receiving transfusions after birth. From 28 studies with alloimmunized pregnant women (7616 women), 455 babies received intrauterine transfusions and 21 received transfusions after birth.

CONCLUSION

Rh, Kell, and MNS were the commonest blood systems involved. The geographical distribution of studies shows that as these figures vary between continents, more studies should be performed in different countries. Investing in early diagnosis is important to manage the risks and complications of hemolytic disease of the fetus and newborn.

Management and Treatment Outcomes of Hemolytic Disease of the Fetus and Newborn (HDFN)-A Retrospective Cohort Study

Background: Hemolytic disease of the fetus and newborn (HDFN) is caused by maternal antibodies attacking fetal blood cell antigens. Despite routine antenatal anti-D prophylaxis, intrauterine transfusions (IUTs) are still needed in some HDFN cases. Methods: We conducted a retrospective cohort study on newborns with HDFN born in the 1st Department of Obstetrics and Gynecology of the Medical University of Warsaw. We analyzed 274 neonates with HDFN, identifying 46 who required IUT due to fetal anemia and 228 who did not. The laboratory results, management, and outcomes were compared between these groups. Results: Comparative analysis showed that newborns treated with IUT were more likely to have significant anemia, hyperbilirubinemia, and iron overload, indicated by a high ferritin concentration. These neonates more often required top-up transfusions, phototherapy, intravenous immunoglobulin infusions, and exchange transfusions. The length of stay was longer for newborns who received IUT. Conclusions: HDFN requiring IUT is associated with a greater number of complications in the neonatal period and more often requires additional treatment compared to HDFN not requiring IUT.

Incidence and Risk Factors of Cholestasis in Newborns with Hemolytic Disease-A Case-Control Study

Background/Objectives: One of the rare causes of cholestasis may be hemolytic disease of the fetus and newborn (HDFN). Methods: We retrospectively analyzed 88 medical records of HDFN newborns with cholestasis and 186 records of children with HDFN without cholestasis and conducted an observational, case-control, retrospective study. Results: Factors influencing the risk of cholestasis were lower gestational age at birth (36.83 ± 1.9 vs. 37.57 ± 1.8, p = 0.002), Rh or Kidd HDFN (80.7% vs. 53.2%), and the need for intrauterine transfusion (27.3 vs. 11.8%). The subjects had lower hemoglobin concentrations at birth (14.01 ± 3.8 vs. 16.39 ± 2.8 g/dL) and during whole hospital stay, higher cord blood total bilirubin concentration (4.26 ± 1.8 vs. 2.39 ± 1.4 mg/dL), higher maximum bilirubin concentration (15.27 ± 5.8 vs. 10.24 ± 3.4 mg/dL), and more frequent liver ultrasound abnormalities (19.9 vs. 6.3%). They also required more extended hospitalization due to higher rates of postnatal blood transfusion (33 vs. 3.8%), more frequent need for exchange transfusion (8.8% vs. 2.2%), more extended time and higher risk of phototherapy (94.3 vs. 59.1%), and higher usage of immunoglobulins (55.7 vs. 8.1%), parenteral nutrition (45.5 vs. 12.9%), and antibiotics (14.8 vs. 4.8%). Conclusions: The risk factors for cholestasis in children with HDFN are lower gestational age at delivery, Rh and Kidd serological type of HDFN, and the need for intrauterine transfusions.

Severe Cholestasis in Neonates with Hemolytic Disease of the Fetus and Newborn-A Case Report

Hemolytic disease of the fetus and newborn (HDFN) may cause severe cholestasis with direct bilirubin concentrations reaching up to 50 times the upper limit of normal. This case report describes twins whose highest direct bilirubin concentrations were 32.2 mg/dL and 50.2 mg/dL, with no significant signs of hepatic impairment. The index pregnancy was complicated by Rhesus factor immunization with anti-D antibodies present in maternal serum, which caused fetal anemia requiring intrauterine blood transfusions. Complementary tests demonstrated Rhesus D alloimmunization as the sole cause of cholestasis. To the best of our knowledge, this is the first study to describe such elevated direct bilirubin concentrations caused by HDFN.

Massive fetomaternal haemorrhage warranting novel use of tandem isovolumetric partial exchange transfusion and therapeutic hypothermia

A newborn male infant was pale, hypotonic, and had respiratory distress after delivery. Venous cord blood gas revealed a severe metabolic acidosis. His initial examination was consistent with moderate encephalopathy and laboratory testing uncovered severe congenital anaemia (haematocrit 0.127 L/L). He met the clinical criteria for therapeutic hypothermia (TH) and required red blood cell transfusions, but due to the severity of his anaemia, an exchange transfusion was favoured to prevent transfusion-associated circulatory overload. There are no previous reports of these procedures completed in tandem, but the benefits were perceived to outweigh the risks. During the 72 hours of TH, the infant received an isovolumetric partial exchange transfusion and tolerated both treatments without any adverse clinical events.Kleihauer-Betke testing detected a massive chronic fetomaternal haemorrhage with 475 mL (164 mL/kg) of blood. A brain MRI completed prior to discharge was normal. At 6 months of age, he is growing and developing normally.

Liver Dysfunction with Severe Cholestasis and Coagulation Disorders in the Course of Hemolytic Disease of the Newborn Requiring Chelation Therapy-A Case Report and Review of the Literature

Severe hemolytic disease of the fetus and newborn (HDFN) requiring intrauterine transfusions (IUTs) may cause iron accumulation, resulting in liver damage, which may lead to cholestasis and coagulation disorders. In this article, we reported a case of a female neonate who underwent chelation therapy with a positive outcome, and we reviewed the English and Polish literature on chelation therapy in HDFN available in PubMed. The patient with maximum ferritin concentration above 33,511.2 ng/mL developed liver dysfunction with coagulation disorders requiring multiple transfusions of fresh frozen plasma (FFP), Octaplex® and cryoprecipitate, and hypoalbuminemia treated with numerous albumin infusions. Furthermore, severe cholestasis was observed with direct bilirubin levels up to 33.14 mg/dL. Additionally, the child developed transient myelosuppression with neutropenia, thrombocytopenia, and low reticulocyte count due to several blood transfusions. The differential diagnosis tests were conducted to rule out any causes of hepatic failure other than hemolytic disease of the newborn. This case proves that adequate treatment of severe HDFN with anemia requiring IUT and hepatic failure can lead to positive outcomes with no long-term consequences.

Hemolytic disease of the fetus and newborn: systematic literature review of the antenatal landscape

BACKGROUND

Prevention of pregnancy-related alloimmunization and the management of hemolytic disease of the fetus and newborn (HDFN) has significantly improved over the past decades. Considering improvements in HDFN care, the objectives of this systematic literature review were to assess the prenatal treatment landscape and outcomes of Rh(D)- and K-mediated HDFN in mothers and fetuses, to identify the burden of disease, to identify evidence gaps in the literature, and to provide recommendations for future research.

METHODS

We performed a systematic search on MEDLINE, EMBASE and clinicaltrials.gov. Observational studies, trials, modelling studies, systematic reviews of cohort studies, and case reports and series of women and/or their fetus with HDFN caused by Rhesus (Rh)D or Kell alloimmunization. Extracted data included prevalence; treatment patterns; clinical outcomes; treatment efficacy; and mortality.

RESULTS

We identified 2,541 articles. After excluding 2,482 articles and adding 1 article from screening systematic reviews, 60 articles were selected. Most abstracted data were from case reports and case series. Prevalence was 0.047% and 0.006% for Rh(D)- and K-mediated HDFN, respectively. Most commonly reported antenatal treatment was intrauterine transfusion (IUT; median frequency [interquartile range]: 13.0% [7.2-66.0]). Average gestational age at first IUT ranged between 25 and 27 weeks. weeks. This timing is early and carries risks, which were observed in outcomes associated with IUTs. The rate of hydrops fetalis among pregnancies with Rh(D)-mediated HDFN treated with IUT was 14.8% (range, 0-50%) and 39.2% in K-mediated HDFN. Overall mean ± SD fetal mortality rate that was found to be 19.8%±29.4% across 19 studies. Mean gestational age at birth ranged between 34 and 36 weeks.

CONCLUSION

These findings corroborate the rareness of HDFN and frequently needed intrauterine transfusion with inherent risks, and most births occur at a late preterm gestational age. We identified several evidence gaps providing opportunities for future studies.

Neonatal sepsis in alloimmune hemolytic disease of the fetus and newborn: A retrospective cohort study of 260 neonates

BACKGROUND

Among neonates with hemolytic disease of the fetus and newborn (HDFN), we aimed to describe the frequency of central-line use, indications for insertion, and incidence of confirmed and suspected sepsis, including antibiotic treatment over a 10-year surveillance period.

STUDY DESIGN AND METHODS

All neonates with HDFN admitted to our neonatal intensive care unit between January 2012 and December 2021 were included in this retrospective, cohort study. Annual proportions of infants with a central-line and central-line-associated bloodstream infection (CLABSI) rates (per 1000 central-line days and per 100 infants) were evaluated. Numbers of confirmed and suspected early- and late-onset sepsis episodes were assessed over the entire study period.

RESULTS

Of the 260 included infants, 25 (9.6%) were evaluated for suspected sepsis, with 16 (6.2%) having ≥1 confirmed sepsis episode. A total of 123 central-lines were placed in 98 (37.7%) neonates, with impending exchange transfusion (ET) being the most frequent indication. Of the 34 (34.7%) neonates in whom a central-line was placed due to impending ET, 11 (32.4%) received no ET. Overall CLABSI incidence was 13.58 per 1000 central-line days. Neonates with a central-line had a higher risk for confirmed late-onset infection (RR 1.11, 95% CI: 1.04-1.20) and sepsis work-up (RR 1.10, 95% CI: 1.03-1.17) compared to infants without a central-line.

CONCLUSIONS

Sepsis incidence among neonates with HDFN remains high, in particular in those with a central-line. Considering the substantial proportion of neonates with a central-line without eventual ET, central-line placement should be delayed until the likelihood of ET is high.

Clinical Profile and Outcome Following Exchange Transfusion for Neonatal Jaundice in a Tertiary Care Centre

INTRODUCTION

Phototherapy has reduced the need for exchange transfusion (ET) to manage jaundiced neonates. Hence there are concerns about increased risk of complication due to lack of opportunity to sustain skills in performing ET. We studied the complications and treatment outcomes of neonates treated for jaundice with ET.

METHODOLOGY

A retrospective observational study was conducted from June 2013 to June 2020 in a tertiary care hospital in India. All neonates treated with ET for jaundice were included.

RESULTS

Twenty-eight neonates underwent 31 ET during the study period. Their mean gestational age and birth weight were 37 weeks and 3200 g, respectively. Predisposing factor for jaundice observed were Coomb's positive status (11), hepatosplenomegaly suggesting hemolysis (3), cephalhematoma (2) and birth asphyxia (1). Abnormal neurological status before ET was seen in seven neonates. Adverse clinical events that happened during or within 8 h after ET were desaturation (4), tachycardia (3), tachypnea (2), bradycardia (2), shock (2) and temperature instability (2). One neonate developed acute kidney injury after ET and required peritoneal dialysis. Abnormal lab parameters observed during or within 8 h after ET were hypocalcemia (20), anemia (8), hypokalemia (7), hypernatremia (3), thrombocytopenia (3) and hyperkalemia (2). Post ET sepsis was seen in five neonates: two had only blood culture positive sepsis, two had bone and joint infection and one had liver abscess.

CONCLUSION

The neonates undergoing ET are at high risk of developing complications which may be life threatening. Hence careful monitoring during the procedure is needed.

Stannsoporfin with phototherapy to treat hyperbilirubinemia in newborn hemolytic disease

OBJECTIVE

To evaluate the efficacy and safety of tin mesoporphyrin (SnMP) in neonates with hyperbilirubinemia (HB) due to hemolysis.

STUDY DESIGN

This multicenter, placebo-controlled phase 2b study (NCT01887327) randomized newborns (35-42 weeks) with hemolysis started on phototherapy (PT) to placebo (Ctrl), SnMP 3.0 mg/kg, or SnMP 4.5 mg/kg given once IM within 30 min of initiation of PT.

RESULTS

In all, 91 patients were randomized (Ctrl: n = 30; 3 mg/kg SnMP: n = 30; 4.5 mg/kg SnMP: n = 31). At 48 h TSB significantly increased in Ctrl by 17.5% (95% CI 5.6-30.7; p = 0.004) and significantly decreased by -13% (95% CI -21.7 to -3.2; p = 0.013) in the 3.0 mg/kg and by -10.5% (95% CI -19.4 to -0.6; p = 0.041) in the 4.5 mg/kg group. Decreases in SnMP groups were significant (p < 0.0001) vs Ctrl.

CONCLUSION

SnMP with PT significantly reduced TSB by 48 h. SnMP may be useful as a treatment for HB in neonates with hemolysis.

Is it necessary to give calcium infusion during the exchange transfusion in newborns?

OBJECTIVES

We aimed to evaluate total serum calcium (TSC) and ionized serum calcium (ISC) levels and their effects on clinical outcomes in neonates underwent exchange transfusion (ET).

METHOD

In this study, the data of newborn infants who underwent ET due to hyperbilirubinemia in a third level neonatal intensive care unit (NICU) were retrospectively analyzed. The patients were monitored by electrocardiogram during ET. Cardiac and respiratory rates, peripheral oxygen saturation, blood pressure values ​​and clinical findings as convulsion, tremor, hypertonia, laryngospasm, cyanosis and apnea were recorded in ET observation forms. The infants with no symptoms of hypocalcemia during the procedure were not routinely given IV calcium gluconate. TSC and ISC measured at the beginning, at the end and 24 h after the end of ET were evaluated retrospectively.

RESULTS

Data of 36 newborn patients were evaluated. Median gestational age was 39 (35-40) weeks, mean birthweight was 2840 ± 841 (mean ± SD) grams. During the ET, desaturation was observed in five patients(13.9 %), sinus bradycardia in six(16.7 %), tachypnea in two(5.5 %), sinus tachycardia in one(2.8 %), and rare ventricular extrasystoles in one(2.8 %). Hypocalcaemia was not detected in any of the patients at the beginning of ET. Hypocalcemia was observed in two cases (5.5 %) at the end of ET. There was no statistically significant difference between the TSC and ISC levels at the beginning of ET, at the end and at the end of 24 h.

CONCLUSION

As a result, routine intravenous (IV) calcium administration seems to be unnecessary provided that vital signs and neurological status are closely monitored during ET.

Exchange transfusions in severe Rh-mediated alloimmune haemolytic disease of the foetus and newborn: a 20-year overview on the incidence, associated risks and outcome

Background and objectives

Guidelines and indications for exchange transfusion in haemolytic disease of the foetus and newborn (HDFN) have changed drastically in the past decades, causing a decline in exchange transfusion rate. This study aims to evaluate the incidence of exchange transfusions (ETs) in neonates with Rh‐mediated HDFN over the past 20 years at our centre, and report potentially ET‐related complications as well as indicators for bilirubin encephalopathy.

Material and methods

In this observational study, 438 neonates were included with HDFN, born ≥ 35 weeks gestational age at the Leiden University Medical Centre between January 2000 and July 2020. The incidence of ET and procedure‐related complications were assessed in three consecutive time periods determined by changes in guidelines and indications for ET.

Results

The incidence of ET in our centre declined from (104/156) 67% (time period 2000–2005), to (39/181) 22% (2006–2015) and to (10/101) 10% (2015–2020, p < 0·001). The maximum bilirubin levels in neonates after birth increased from 13·6 mg/dL (or 233 μmol/L), to 15·0 mg/dL (257 μmol/L) and to 15·3 mg/dL (263 μmol/L). The incidence of complications associated with the use of ET (including sepsis, haematologic disorders and respiratory failure) remained stable throughout the years, and no neonates died during the study period.

Conclusion

Exchange transfusion incidence declined significantly over the past two decades. Decrease in ET incidence, and concomitant decrease in exposure and expertise, was not associated with an increase in procedure‐related complications.

Are fetal bilirubin levels associated with the need for neonatal exchange transfusions in hemolytic disease of the fetus and newborn?

BACKGROUND

Fetal bilirubin is routinely measured at our center when taking a pretransfusion blood sample at intrauterine transfusions in hemolytic disease of the fetus and newborn. However, the clinical value of fetal bilirubin assessment is not well known, and the information is rarely used. We speculated that there could be a role for this measurement in predicting the need for neonatal exchange transfusion.

OBJECTIVE

This study aimed to evaluate the predictive value of fetal bilirubin for exchange transfusions in severe hemolytic disease of the fetus and newborn.

STUDY DESIGN

A total of 186 infants with Rh alloantibody-mediated hemolytic disease of the fetus and newborn treated with one or more intrauterine transfusions at the Leiden University Medical Center between January 2006 and June 2020 were included in this observational study. Antenatal and postnatal factors were compared between infants with and without exchange transfusion treatments. The primary outcome was the fetal bilirubin levels before the last intrauterine transfusion in relation to the need for exchange transfusion.

RESULTS

In a multivariate logistic regression analysis, the fetal bilirubin level before the last intrauterine transfusions (odds ratio, 1.32; 95% confidence interval, 1.09-1.61 per 1 mg/dL) and the total number of intrauterine transfusions (odds ratio, 0.63; 95% confidence interval, 0.44-0.91 per intrauterine transfusion) were independently associated with the need for exchange transfusion. The area under the curve was determined at 0.71. A Youden index was calculated at 0.43. The corresponding fetal bilirubin level was 5 mg/dL and had a sensitivity of 79% and a specificity of 64%.

CONCLUSION

A high fetal bilirubin level before the last intrauterine transfusion was associated with a high likelihood of neonatal exchange transfusion.

Can bilirubin/albumin ratio predict neurodevelopmental outcome in severe neonatal hyperbilirubinemia? A 3-month follow up study

Background

The risk of kernicterus and BIND may be in part determined by total serum bilirubin (TSB) and by the level of non-albumin bound free bilirubin, which can easily pass the blood–brain barrier. Free bilirubin (Bf) seems a more reliable predictor for bilirubin neurotoxicity. Bilirubin/albumin ratio (B/A) is considered a surrogate parameter for Bf and has been more useful than TSB. The aim of the study is to determine whether B/A ratio correlates with BIND in newborns with severe hyperbilirubinemia and if it can predict poor neurologic outcome at 3 months follow up.

Results

This prospective study included one hundred seventeen outborn neonates ≥ 35 weeks admitted in a tertiary care neonatal intensive care unit, between May and December 2012, with TSB ≥ 20 mg/dl or necessitating exchange transfusion. Total serum bilirubin and serum albumin were done on admission and bilirubin/albumin ratio was calculated. BIND score was calculated. At the age of 3 months, 112 neonates were followed up with a detailed neurological assessment. Babies who depicted any abnormal motor examination were subjected to brain stem auditory evoked response and MRI examination. Seven infants (6.2%) presented with kernicterus on follow up. BIND scores on admission, mean TSB, and bilirubin/albumin ratio was significantly higher in kernicteric infants compared with those having normal neurological outcome at 3 months of age (P 0.001). The lowest TSB level at which kernicterus occurred in our study was 31 mg/dl. Receiver operation characteristics analysis identified B/A ratio cut off value for predicting kernicterus of 9.6 with sensitivity of 100% and specificity of 91.4%, whereas TSB cut off value of 30 mg/dl showed sensitivity of 100% and specificity of 83%.

Conclusion

B/A ratio is a strong indicator for the risk of kernicterus. B/A is more specific than TSB and should be used in the early management of neonatal hyperbilirubinemia.

Neonatal outcomes after percutaneous umbilical cord blood sampling†

Objectives: While percutaneous umbilical cord blood sampling (PUBS) and intrauterine transfusion (IUT) are the standards of care for the management of significant fetal anemia, the neonatal complications resultant from these procedures remain poorly understood. Thus, we aimed to compare neonatal outcomes of the patients undergoing percutaneous umbilical cord blood sampling (PUBS) for intrauterine transfusion (IUT) to gestational age- and sex-matched controls with no indication for and not undergoing PUBS.Methods: This was a retrospective matched cohort study at a single institution from 2000 to 2017. Clinical and demographic data were abstracted from the medical record of patients undergoing PUBS. Neonatal outcomes from pregnancies undergoing PUBS for suspected fetal anemia and from randomly selected gestational age- and sex-matched controls were collected. Neonatal outcomes were compared using matched pairs analysis.Results: There were 64 patients who underwent a total of 178 PUBS with 157 IUT. The most common etiology of fetal anemia was anti-D alloimmunization. On an average, patients undergoing PUBS underwent two procedures (IQR 1,4). There were available neonatal outcomes in 40 patients. The median gestational age at delivery was 34 weeks in both neonates who underwent PUBS and controls. In matched pairs analysis, neonates who underwent PUBS were at higher risk for neonatal complications compared to control neonates (92.5 vs. 55%, OR 4.5, 95% CI 4.5, ∞) . Specifically, neonates who underwent PUBS were more likely to experience respiratory complications compared to controls despite a higher uptake of antenatal corticosteroids.Conclusions: We found that neonates who underwent PUBS experience a higher occurrence of complications which does not appear to be secondary to prematurity alone. Despite higher uptake of antenatal corticosteroids in neonates who underwent PUBS as compared to control neonates, neonates who underwent PUBS had a higher risk of respiratory complications. This study can help to inform patients undergoing PUBS/IUT on the anticipated neonatal outcomes and anticipate needed neonatology resources. While PUBS/IUT is the best treatment known to date for management of fetal anemia, our study highlights the need for further research into the subsequent neonatal complications and how to prevent them.

Potential Consequences of the Red Blood Cell Storage Lesion on Cardiac Electrophysiology

Background The red blood cell (RBC) storage lesion is a series of morphological, functional, and metabolic changes that RBCs undergo following collection, processing, and refrigerated storage for clinical use. Since the biochemical attributes of the RBC unit shifts with time, transfusion of older blood products may contribute to cardiac complications, including hyperkalemia and cardiac arrest. We measured the direct effect of storage age on cardiac electrophysiology and compared it with hyperkalemia, a prominent biomarker of storage lesion severity. Methods and Results Donor RBCs were processed using standard blood-banking techniques. The supernatant was collected from RBC units, 7 to 50 days after donor collection, for evaluation using Langendorff-heart preparations (rat) or human induced pluripotent stem cell-derived cardiomyocytes. Cardiac parameters remained stable following exposure to "fresh" supernatant from red blood cell units (day 7: 5.8±0.2 mM K+), but older blood products (day 40: 9.3±0.3 mM K+) caused bradycardia (baseline: 279±5 versus day 40: 216±18 beats per minute), delayed sinus node recovery (baseline: 243±8 versus day 40: 354±23 ms), and increased the effective refractory period of the atrioventricular node (baseline: 77±2 versus day 40: 93±7 ms) and ventricle (baseline: 50±3 versus day 40: 98±10 ms) in perfused hearts. Beating rate was also slowed in human induced pluripotent stem cell-derived cardiomyocytes after exposure to older supernatant from red blood cell units (-75±9%, day 40 versus control). Similar effects on automaticity and electrical conduction were observed with hyperkalemia (10-12 mM K+). Conclusions This is the first study to demonstrate that "older" blood products directly impact cardiac electrophysiology, using experimental models. These effects are likely caused by biochemical alterations in the supernatant from red blood cell units that occur over time, including, but not limited to hyperkalemia. Patients receiving large volume and/or rapid transfusions may be sensitive to these effects.

Immunohematologic aspects of alloimmunization and alloantibody detection: A focus on pregnancy and hemolytic disease of the fetus and newborn

Alloimmunization to non-ABO, red blood cell (RBC) antigens remains one of the most clinically-relevant complexities faced by blood banking practitioners. In the setting of transfusion therapy, these antibodies raise risks for incompatibilities, while for pregnant patients they can mediate deadly forms of hemolytic disease of the fetus and newborn. As such, a thorough understanding of pathways that lead to alloimmunization, as well as the tools used by blood banks to detect alloantibodies, is critical to transfusion practice. In this review, in which alloimmunization in the setting of pregnancy will be emphasized, we will review: 1) the clinical impacts of RBC alloantibodies in the peri-partum period; 2) the current pathophysiologic mechanisms thought to influence non-ABO antigen alloimmunization; 3) the strengths and weaknesses of laboratory tools used in aiding alloimmunization detection; and 4) future directions of the transfusion community related to alloimmunization impacting pregnancy.

A single heterochronic blood exchange reveals rapid inhibition of multiple tissues by old blood

Heterochronic parabiosis rejuvenates the performance of old tissue stem cells at some expense to the young, but whether this is through shared circulation or shared organs is unclear. Here we show that heterochronic blood exchange between young and old mice without sharing other organs, affects tissues within a few days, and leads to different outcomes than heterochronic parabiosis. Investigating muscle, liver and brain hippocampus, in the presence or absence of muscle injury, we find that, in many cases, the inhibitory effects of old blood are more pronounced than the benefits of young, and that peripheral tissue injury compounds the negative effects. We also explore mechanistic explanations, including the role of B2M and TGF-beta. We conclude that, compared with heterochronic parabiosis, heterochronic blood exchange in small animals is less invasive and enables better-controlled studies with more immediate translation to therapies for humans.

Joining the circulatory system of an old with a young animal has been shown to rejuvenate old tissues. Here the authors describe a comparatively simple blood infusion system that allows for the controlled exchange of blood between two animals, and study the effects of a single exchange on various tissues.

Perinatal survival and procedure-related complications after intrauterine transfusion for red cell alloimmunization

OBJECTIVES

To study the perinatal survival and procedure-related (PR)complications after intrauterine transfusions in red cell alloimmunization.

METHODS

Prospective data of 102 women with Rh-alloimmunized pregnancy undergoing intrauterine intravascular transfusion for fetal anemia, from January 2011 to October 2014 were analyzed. Main outcome measures were perinatal survival and procedure-related (PR) complications.

RESULTS

A total of 303 intrauterine transfusions were performed in 102 women. Of 102 fetuses, 22 were hydropic at first transfusion. The mean period of gestation and hematocrit at first transfusion was 26.9 ± 3.3 weeks (range 19.7-33.8 weeks) and 17 ± 7.82 % (range 5.7-30 %), respectively. Average number of transfusions was 2.97 (range 1-7) per patient. Overall survival was 93 % and mean period of gestation at delivery was 34.5 ± 1.94 (range 28.3-37.4) weeks. Mean hematocrit at delivery was 36.9 ± 8.77 % (range 10-66 %). Fetal death occurred in four cases (3PR), neonatal death occurred in three cases (2PR). Emergency cesarean delivery after transfusion was performed in four pregnancies. The total PR complication rate was 2.97 %, resulting in overall PR loss in 1.65 % per procedure.

CONCLUSION

Our results compare favorably with other studies published in the literature. Intravascular transfusion is a safe procedure improving perinatal survival in fetuses with anemia due to Rh-alloimmunization.

Zinc supplementation for neonatal hyperbilirubinemia: a randomized controlled trial

OBJECTIVE

To determine the efficacy of oral zinc for treatment of idiopathic neonatal hyperbilirubinemia in near-term and term (35-41 weeks) neonates.

DESIGN

Randomized placebo-controlled trial.

SETTING

Tertiary-care teaching hospital.

PARTICIPANTS

Eighty newborns with idiopathic neonatal hyperbilirubinemia.

INTERVENTION

Neonates were randomized to receive either oral zinc sulfate (10 mg/d) or placebo for 7 days.

MAIN OUTCOME MEASURES

Primary: total serum bilirubin levels at 48 (±12) h, 96 (±12) h and 144 (±12) h after intervention. Secondary: duration of phototherapy, and serum zinc and copper levels.

RESULTS

Baseline mean (SD) total serum bilirubin levels were 14.8 (3.8) and 14.4 (3.5) mg/dL in zinc and placebo groups, respectively. No significant differences were observed in total bilirubin levels between the two groups after the intervention. Mean (SD) total serum bilirubin levels in zinc and placebo groups were 13.9 (2.5) vs. 13.4 (1.9) mg/dL (mean difference 0.566; 95% CI -0.535, 1.668, P=0.038) at 48 h, 13.1 (2.7) vs. 12.8 (2.3) mg/dL (mean difference 0.234; 95% CI -1.011, 1.479, P =0.708) at 96 h and 8.0 (2.0) vs. 8.6 (1.2) mg/dL (mean difference -0.569, 95% CI -1.382, 0.242, P=0.166) at 144 h. Although the mean duration of phototherapy in the zinc group was less by 21.3 h (95% CI 11.6, 30.9, P=0.052), the difference was not significant. Post-intervention, serum zinc levels were significantly higher in the zinc-supplemented group while serum copper levels were comparable between the two groups.

CONCLUSIONS

Oral zinc sulfate, in a dose of 10 mg/day, is not effective in the management of idiopathic neonatal hyperbilirubinemia.

Exchange Transfusion for Severe Neonatal Hyperbilirubinemia: 17 Years' Experience from Vojvodina, Serbia

This study aimed to evaluate the frequency of the main risk factors for severe neonatal hyperbilirubinemia, to determine the incidence of exchange transfusion (ET) in the Autonomous Province of Vojvodina (the northern part of Serbia) and to describe the experience with ET performed in premature and term infants during the past 17 years. We performed a retrospective data analysis of 398 newborn infants who underwent a double volume ET from 1997 to 2013. During the 17 year study period, a decreasing incidence of ET, expressed per thousand newborns, was observed. A total of 468 double volume ET were performed: 328 (82.4 %) infants had one treatment and 70 (17.6 %) had repeated treatments. A total of 262,830 mLs of blood were transfused, an average of 660 mLs per child. There were 221 male and 177 female infants, with a sex ratio 1.25:1. The frequencies of risk factors for developing hyperbilirubinemia were as follows: (1) 38 % RhD incompatibility; (2) 38 % ABO incompatibility (26 % group A infant of group O mother, 12 % group B infant of group O mother); (3) 7 % low birth weight/preterm birth; (4) 17 % other factors. Risk factors for neurotoxicity were identified in 56.3 % of infants. No deaths or complications were reported arising from the treatment. ABO and Rh incompatibilities were found to be the main risk factors for severe neonatal hyperbilirubinemia in Vojvodina. Exchange transfusion, used as therapy for severe hyperbilirubinemia, trended downwards over the period of this study.

Serum bilirubin and bilirubin/albumin ratio as predictors of bilirubin encephalopathy

BACKGROUND AND OBJECTIVE

Bilirubin/albumin ratio (B/A) may provide a better estimate of free bilirubin than total serum bilirubin (TSB), thus improving identification of newborns at risk for bilirubin encephalopathy. The objective of the study was to identify thresholds and compare specificities of TSB and B/A in detecting patients with acute and posttreatment auditory and neurologic impairment.

METHODS

A total of 193 term/near-term infants, admitted for severe jaundice to Cairo University Children's Hospital, were evaluated for neurologic status and auditory impairment (automated auditory brainstem response), both at admission and posttreatment by investigators blinded to laboratory results. The relationships of TSB and B/A to advancing stages of neurotoxicity were compared by using receiver operating characteristic curves.

RESULTS

TSB and B/A ranged from 17 to 61 mg/dL and 5.4 to 21.0 mg/g, respectively; 58 (30%) of 193 subjects developed acute bilirubin encephalopathy, leading to kernicterus in 35 infants (13 lethal). Auditory impairment was identified in 86 (49%) of 173 infants at admission and in 22 of 128 at follow-up. In the absence of clinical risk factors, no residual neurologic or hearing impairment occurred unless TSB exceeded 31 mg/dl. However, transient auditory impairment occurred at lower TSB and B/A (22.9 mg/dL and 5.7 mg/g, respectively). Intervention values of TSB and B/A set at high sensitivity to detect different stages of neurotoxicity had nearly the same specificity.

CONCLUSIONS

Both TSB and B/A are strong predictors of neurotoxicity, but B/A does not improve prediction over TSB alone. Threshold values detecting all affected patients (100% sensitivity) increase with advancing severity of neurotoxicity.