Clinical Practice Guideline for Red Blood Cell Transfusion Thresholds in Very Preterm Neonates.

Importance: Red blood cell (RBC) transfusion is a common medical intervention to treat anemia in very preterm neonates; however, best transfusion practices, such as thresholds, remain uncertain. Objective: To develop recommendations for clinicians on the use of RBC transfusions in very preterm neonates. Evidence Review: An international steering committee reviewed evidence from a systematic review of 6 randomized clinical trials (RCTs) that compared high vs low hemoglobin-based or hematocrit-based transfusion thresholds. The steering committee reached consensus on certainty-of-evidence ratings and worked with a panel from stakeholder organizations on reviewing the evidence. With input from parent representatives and the stakeholder panel, the steering committee used the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) approach to develop recommendations. Findings: A systematic review of 6 RCTs encompassing 3483 participants (1759 females [51.3%]; mean [SD] age range, 25.9-29.8 [1.5-3.0] weeks) was used as the basis of the recommendations. The ranges for higher hemoglobin concentration (liberal) vs lower hemoglobin concentration (restrictive) threshold study arms were similar across the trials. However, specific thresholds differed based on the severity of illness, which was defined using variable criteria in the trials. There was moderate certainty of evidence that low transfusion thresholds likely had little to no difference in important short-term and long-term outcomes. The recommended hemoglobin thresholds varied on the basis of postnatal week and respiratory support needs. At postnatal weeks 1, 2, and 3 or more, for neonates on respiratory support, the recommended thresholds were 11, 10, and 9 g/dL, respectively; for neonates on no or minimal respiratory support, the recommended thresholds were 10, 8.5, and 7 g/dL, respectively (to convert hemoglobin to grams per liter, multiply by 10.0). Conclusions and Relevance: This consensus statement recommends a restrictive RBC transfusion strategy, with moderate certainty of evidence, for preterm neonates with less than 30 weeks' gestation.

Evaluation of the impact of diagnostic blood loss and red blood cell transfusion in very-low-birth-weight anaemic neonates during hospitalization: A multi-centre retrospective clinical study.

BACKGROUND AND OBJECTIVES: Diagnostic blood loss is a significant factor in the development of anaemia in neonates with very low birth weight. This study aimed to assess the clinical efficacy of intervention approaches involving varying diagnostic blood loss and red blood cell transfusion volumes in neonates with very low birth weights experiencing anaemia during hospitalization. MATERIALS AND METHODS: A total of 785 newborns with anaemia weighing less than 1500 g were enrolled from 32 hospitals in China. The study involved monitoring diagnostic blood loss and red blood cell transfusion and evaluating relevant interventions such as red blood cell transfusion and clinical outcomes. Three intervention approaches were established based on the difference between blood loss and transfusion (Intervention Approaches 0, 1 and 2). The primary outcomes measured were unsatisfactory weight gain during hospitalization and neonatal mortality. The secondary outcomes included related complications. RESULTS: In the non-hospital-acquired anaemia group, Intervention Approach 2 had the highest incidence of below-normal weight gain (odds ratio [OR]: 3.019, 95% confidence interval [CI]: 1.081-8.431, p = 0.035). Multivariate analysis revealed that Intervention Approach 1 had a protective effect on weight gain. In the hospital-acquired anaemia group, Intervention Approach 2 had the highest incidence of below-normal weight gain (OR: 3.335, 95% CI: 1.785-6.234, p = 0.000) and mortality (OR: 5.341, 95% CI: 2.449-11.645, p = 0.000), while Intervention Approach 1 had the lowest incidence of intraventricular haemorrhage. Intervention Approach 1 demonstrated favourable outcomes in both anaemia groups. CONCLUSION: Intervention Approach 1 improved weight gain and reduced mortality and complications in both the non-hospital-acquired and hospital-acquired anaemia groups.

Allogeneic cord blood transfusions prevent fetal haemoglobin depletion in preterm neonates. Results of the CB-TrIP study.

Repeated red blood cell (RBC) transfusions in preterm neonates are associated with poor outcome and increased risk for prematurity-associated diseases. RBC transfusions cause the progressive replacement of fetal haemoglobin (HbF) by adult haemoglobin (HbA). We monitored HbF levels in 25 preterm neonates until 36 weeks of post-menstrual age (PMA); patients received RBC units from allogeneic cord blood (cord-RBCs) or from adult donors (adult-RBCs), depending on whether cord-RBCs were available. Primary outcome was HbF level at PMA of 32 weeks. Twenty-three neonates survived until this age: 14 received no transfusions, two only cord-RBCs, three only adult-RBCs and four both RBC types. HbF levels in neonates transfused with cord-RBCs were significantly higher than in neonates receiving adult-RBCs (P < 0·0001) or both RBC types (P < 0·0001). Superimposable results were obtained at PMA of 36 weeks. Every adult-RBCs transfusion increased the risk for an HbF in the lowest quartile by about 10-fold, whereas this effect was not evident if combined adult- and cord-RBCs were evaluated. Overall, these data show that transfusing cord-RBCs can limit the HbF depletion caused by conventional RBC transfusions. Transfusing cord blood warrants investigation in randomised trials as a strategy to mitigate the severity of retinopathy of prematurity (NCT03764813).

Early versus late erythropoietin for preventing red blood cell transfusion in preterm and/or low birth weight infants.

BACKGROUND: Low plasma levels of erythropoietin (EPO) in preterm infants provide a rationale for the use of EPO to prevent or treat anaemia. OBJECTIVES: To assess the effectiveness and safety of early versus late initiation of EPO in reducing red blood cell (RBC) transfusions in preterm and/or low birth weight (LBW) infants. SEARCH METHODS: The standard search of the Cochrane Neonatal Review Group (CNRG) was performed in 2006 and updated in 2009. Updated search in September 2009 as follows: The Cochrane Library, MEDLINE (search via PubMed), CINAHL and EMBASE were searched from 2005 to September 2009. The searches were repeated in March 2012. The Pediatric Academic Societies' Annual meetings were searched electronically from 2000 to 2012 at Abstracts2ViewTM as were clinical trials registries (clinicaltrials.gov; controlled-trials.com; and who.int/ictrp). SELECTION CRITERIA: Randomised or quasi-randomised controlled trials enrolling preterm or LBW infants less than eight days of age. INTERVENTION: Early initiation of EPO (initiated at less than eight days of age) versus late initiation of EPO (initiated at eight to 28 days of age). DATA COLLECTION AND ANALYSIS: The standard methods of the CNRG were followed. Weighted treatment effects included typical risk ratio (RR), typical risk difference (RD), number needed to treat to benefit (NNTB), number needed to treat to harm (NNTH) and mean difference (MD), all with 95% confidence intervals (CI). A fixed-effect model was used for meta-analyses and heterogeneity was evaluated using the I-squared (I2) test. MAIN RESULTS: No new trials were identified in March of 2012. Two high quality randomised double-blind controlled studies enrolling 262 infants were identified. A non-significant reduction in the 'Use of one or more RBC transfusions' [two studies 262 infants; typical RR 0.91 (95% CI 0.78 to 1.06); typical RD -0.07 (95% CI -0.18 to 0.04; I2 = 0% for both RR and RD] favouring early EPO was noted. Early EPO administration resulted in a non-significant reduction in the "number of transfusions per infant" compared with late EPO [typical MD - 0.32 (95% CI -0.92 to 0.29)]. There was no significant reduction in total volume of blood transfused per infant or in the number of donors to whom the infant was exposed. Early EPO led to a significant increase in the risk of retinopathy of prematurity (ROP) (all stages) [two studies, 191 infants; typical RR 1.40 (95% CI 1.05 to 1.86); typical RD 0.16 (95% CI 0.03 to 0.29); NNTH 6 (95% CI 3 to 33)]. There was high heterogeneity for this outcome (I2 = 86% for RR and 81% for RD). Both studies (191 infants) reported on ROP stage > 3. No statistically significant increase in risk was noted [typical RR 1.56 (95% CI 0.71 to 3.41); typical RD 0.05 (-0.04 to 0.14)] There was no heterogeneity for this outcome (0% for both RR and RD). No other important favourable or adverse neonatal outcomes or side effects were reported. AUTHORS' CONCLUSIONS: The use of early EPO did not significantly reduce the 'Use of one or more RBC transfusions' or the 'Number of transfusions per infant" compared with late EPO administration. The finding of a statistically significant increased risk of ROP (any grade) and a similar trend for ROP stage > 3 with early EPO treatment is of great concern.

Early erythropoiesis-stimulating agents in preterm or low birth weight infants.

BACKGROUND: Preterm infants have low plasma levels of erythropoietin (EPO), providing a rationale for the use of erythropoiesis-stimulating agents (ESAs) to prevent or treat anaemia and to provide neuro protection and protection against necrotising enterocolitis (NEC). Darbepoetin (Darbe) and EPO are currently available ESAs. OBJECTIVES: To assess the effectiveness and safety of ESAs (erythropoietin (EPO) and/or Darbe) initiated early (before eight days after birth) compared with placebo or no intervention in reducing red blood cell (RBC) transfusions, adverse neurological outcomes, and feeding intolerance including necrotising enterocolitis (NEC) in preterm and/or low birth weight infants. Primary objective for studies that primarily investigate the effectiveness and safety of ESAs administered early in reducing red blood cell transfusions: To assess the effectiveness and safety of ESAs initiated early in reducing red blood cell transfusions in preterm infants. Secondary objectives: Review authors performed subgroup analyses of low (≤ 500 IU/kg/week) and high (> 500 IU/kg/week) doses of EPO and the amount of iron supplementation provided: none, low (≤ 5 mg/kg/d), and high (> 5 mg/kg/d). Primary objective for studies that primarily investigate the neuro protective effectiveness of ESAs: To assess the effectiveness and safety of ESAs initiated early in reducing adverse neurological outcomes in preterm infants. Primary objective for studies that primarily investigate the effectiveness of EPO or Darbe administered early in reducing feeding intolerance: To assess the effectiveness and safety of ESAs administered early in reducing feeding intolerance (and NEC) in preterm infants. Other secondary objectives: To compare the effectiveness of ESAs in reducing the incidence of adverse events and improving long-term neurodevelopmental outcomes. SEARCH METHODS: We used the standard search strategy of Cochrane Neonatal to search the Cochrane Central Register of Controlled Trials (CENTRAL; 2017, Issue 2), MEDLINE via PubMed (1966 to 10 March 2017), Embase (1980 to 10 March 2017), and the Cumulative Index to Nursing and Allied Health Literature (CINAHL; 1982 to 10 March 2017). We searched clinical trials databases, conference proceedings, and reference lists of retrieved articles for randomised and quasi-randomised controlled trials. SELECTION CRITERIA: Randomised and quasi-randomised controlled trials of early initiation of EAS treatment versus placebo or no intervention in preterm or low birth weight infants. DATA COLLECTION AND ANALYSIS: We used the methods described in the Cochrane Handbook for Systematic Reviews of Interventions and the GRADE approach to assess the quality of evidence. MAIN RESULTS: This updated review includes 34 studies enrolling 3643 infants. All analyses compared ESAs versus a control consisting of placebo or no treatment. Early ESAs reduced the risk of 'use of one or more [red blood cell] RBC transfusions' (typical risk ratio (RR) 0.79, 95% confidence interval (CI) 0.74 to 0.85; typical risk difference (RD) -0.14, 95% CI -0.18 to -0.10; I2 = 69% for RR and 62% for RD (moderate heterogeneity); number needed to treat for an additional beneficial outcome (NNTB) 7, 95% CI 6 to 10; 19 studies, 1750 infants). The quality of the evidence was low. Necrotising enterocolitis was significantly reduced in the ESA group compared with the placebo group (typical RR 0.69, 95% CI 0.52 to 0.91; typical RD -0.03, 95% CI -0.05 to -0.01; I2 = 0% for RR and 22% for RD (low heterogeneity); NNTB 33, 95% CI 20 to 100; 15 studies, 2639 infants). The quality of the evidence was moderate. Data show a reduction in 'Any neurodevelopmental impairment at 18 to 22 months' corrected age in the ESA group (typical RR 0.62, 95% CI 0.48 to 0.80; typical RD -0.08, 95% CI -0.12 to -0.04; NNTB 13, 95% CI 8 to 25. I2 = 76% for RR (high heterogeneity) and 66% for RD (moderate); 4 studies, 1130 infants). The quality of the evidence was low. Results reveal increased scores on the Bayley-II Mental Development Index (MDI) at 18 to 24 months in the ESA group (weighted mean difference (WMD) 8.22, 95% CI 6.52 to 9.92; I2 = 97% (high heterogeneity); 3 studies, 981 children). The quality of the evidence was low. The total volume of RBCs transfused per infant was reduced by 7 mL/kg. The number of RBC transfusions per infant was minimally reduced, but the number of donors to whom infants who were transfused were exposed was not significantly reduced. Data show no significant difference in risk of stage ≥ 3 retinopathy of prematurity (ROP) with early EPO (typical RR 1.24, 95% CI 0.81 to 1.90; typical RD 0.01, 95% CI -0.02 to 0.04; I2 = 0% (no heterogeneity) for RR; I2 = 34% (low heterogeneity) for RD; 8 studies, 1283 infants). Mortality was not affected, but results show significant reductions in the incidence of intraventricular haemorrhage (IVH) and periventricular leukomalacia (PVL). AUTHORS' CONCLUSIONS: Early administration of ESAs reduces the use of red blood cell (RBC) transfusions, the volume of RBCs transfused, and donor exposure after study entry. Small reductions are likely to be of limited clinical importance. Donor exposure probably is not avoided, given that all but one study included infants who had received RBC transfusions before trial entry. This update found no significant difference in the rate of ROP (stage ≥ 3) for studies that initiated EPO treatment at less than eight days of age, which has been a topic of concern in earlier versions of this review. Early EPO treatment significantly decreased rates of IVH, PVL, and NEC. Neurodevelopmental outcomes at 18 to 22 months and later varied in published studies. Ongoing research should evaluate current clinical practices that will limit donor exposure. Promising but conflicting results related to the neuro protective effect of early EPO require further study. Very different results from the two largest published trials and high heterogeneity in the analyses indicate that we should wait for the results of two ongoing large trials before drawing firm conclusions. Administration of EPO is not currently recommended because limited benefits have been identified to date. Use of darbepoetin requires further study.

Late erythropoiesis-stimulating agents to prevent red blood cell transfusion in preterm or low birth weight infants.

BACKGROUND: Preterm infants have low plasma levels of erythropoietin (EPO), providing a rationale for the use of erythropoiesis-stimulating agents (ESAs) to prevent or treat anaemia. Darbepoetin (Darbe) and EPO are currently available ESAs. OBJECTIVES: To assess the effectiveness and safety of late initiation of ESAs, between eight and 28 days after birth, in reducing the use of red blood cell (RBC) transfusions in preterm or low birth weight infants. SEARCH METHODS: We used the standard search strategy of Cochrane Neonatal to search the Cochrane Central Register of Controlled Trials (CENTRAL 2018, Issue 5), MEDLINE via PubMed (1966 to 5 June 2018), Embase (1980 to 5 June 2018), and CINAHL (1982 to 5 June 2018). We searched clinical trials databases, conference proceedings, and the reference lists of retrieved articles for randomised controlled trials and quasi-randomised trials. SELECTION CRITERIA: Randomised or quasi-randomised controlled trials of late initiation of EPO treatment (started at ≥ eight days of age) versus placebo or no intervention in preterm (< 37 weeks) or low birth weight (< 2500 grams) neonates. DATA COLLECTION AND ANALYSIS: We performed data collection and analyses in accordance with the methods of the Cochrane Neonatal Review Group. We used the GRADE approach to assess the quality of the evidence. MAIN RESULTS: We include 31 studies (32 comparisons) randomising 1651 preterm infants. Literature searches in 2018 identified one new study for inclusion. No new on-going trials were identified and no studies used darbepoetin. Most included trials were of small sample size. The meta-analysis showed a significant effect on the use of one or more RBC transfusions (21 studies (n = 1202); typical risk ratio (RR) 0.72, 95% confidence interval (CI) 0.65 to 0.79; typical risk difference (RD) -0.17, 95% CI -0.22 to -0.12; typical number needed to treat for an additional beneficial outcome (NNTB) 6, 95% CI 5 to 8). There was moderate heterogeneity for this outcome (RR I² = 66%; RD I² = 58%). The quality of the evidence was very low. We obtained similar results in secondary analyses based on different combinations of high/low doses of EPO and iron supplementation. There was no significant reduction in the total volume (mL/kg) of blood transfused per infant (typical mean difference (MD) -1.6 mL/kg, 95% CI -5.8 to 2.6); 5 studies, 197 infants). There was high heterogeneity for this outcome (I² = 92%). There was a significant reduction in the number of transfusions per infant (11 studies enrolling 817 infants; typical MD -0.22, 95% CI -0.38 to -0.06). There was high heterogeneity for this outcome (I² = 94%). Three studies including 404 infants reported on retinopathy of prematurity (ROP) (all stages or stage not reported), with a typical RR 1.27 (95% CI 0.99 to 1.64) and a typical RD of 0.09 (95% CI -0.00 to 0.18). There was high heterogeneity for this outcome for both RR (I² = 83%) and RD (I² = 82%). The quality of the evidence was very low.Three trials enrolling 442 infants reported on ROP (stage ≥ 3). The typical RR was 1.73 (95% CI 0.92 to 3.24) and the typical RD was 0.05 (95% CI -0.01 to 0.10). There was no heterogeneity for this outcome for RR (I² = 18%) but high heterogeneity for RD (I² = 79%). The quality of the evidence was very low.There were no significant differences in other clinical outcomes including mortality and necrotising enterocolitis. For the outcomes of mortality and necrotising enterocolitis, the quality of the evidence was moderate. Long-term neurodevelopmental outcomes were not reported. AUTHORS' CONCLUSIONS: Late administration of EPO reduces the use of one or more RBC transfusions, the number of RBC transfusions per infant (< 1 transfusion per infant) but not the total volume (mL/kg) of RBCs transfused per infant. Any donor exposure is likely not avoided as most studies included infants who had received RBC transfusions prior to trial entry. Late EPO does not significantly reduce or increase any clinically important adverse outcomes except for a trend in increased risk for ROP. Further research of the use of late EPO treatment, to prevent donor exposure, is not indicated. Research efforts should focus on limiting donor exposure during the first few days of life in sick neonates, when RBC requirements are most likely to be required and cannot be prevented by late EPO treatment. The use of satellite packs (dividing one unit of donor blood into many smaller aliquots) may reduce donor exposure.

Infantile Pyknocytosis: An Uncommon Cause of Newborn Hemolytic Anemia.

Infantile pyknocytosis is a rare cause of neonatal hemolytic anemia, which presents in the first few weeks of life. We report a classic case of infantile pyknocytosis that presented to our institution with rebound hyperbilirubinemia after receiving phototherapy. The infant was found to have a hemoglobin of 5.8 g/dL, requiring a total of 15 mL/kg of red blood cells (in 2 separate transfusions) before discharge. The diagnosis was ultimately made by a review of the peripheral blood smear. We review the literature and suggest pediatricians consider infantile pyknocytosis on their differential when hemolytic anemia presents in the newborn period.

The role of recombinant Human erythropoietin in neonatal anemia.

AIM: To estimate the blood level of Erythropoietin(EPO) in neonates with anemia of prematurity (APO) and in late hypo-regenerative anemia and to clarify role of EPO in correction of anemia and reducing the number of blood transfusions. METHODS: This study was carried out on 60 neonates divided into; group I (30 preterm neonates) with AOP received EPO (250 IU/kg/dose subcutaneously 3 times weekly for 4 weeks), compared to group II (30 neonates) with AOP treated only with blood transfusion. CBC parameters and transfusion requirements were followed during therapy. Serum level of EPO was measured by ELISA technique. RESULTS: By the end of the 4th week of therapy, there was significant increase in group I post r-Hu EPO compared to group II regarding reticulocyte counts (P < 0.001) leading to rise of the Hb (P < 0.001), Hct levels (P < 0.001) with subsequent reduction in the overall number of blood transfusions (P < 0.001). CONCLUSION: EPO therapy in conjunction with iron, vitamin E and folic acid, stimulated erythropoiesis and significantly reduced the need for blood transfusion in AOP.

What Is New about Transfusions for Preterm Infants? An Update.

Currently the question of whether to maintain a higher hemoglobin level by transfusing more liberally, as opposed to a more restrictive strategy with lower hemoglobin maintenance levels, has not been answered. We review summarized conclusions of a Cochrane systematic review and meta-analysis of 614 infants in 4 randomized controlled trials (RCT) pooling data. This suggests potential benefits of higher hemoglobin levels, i.e., a possible improved cognition of infants at 18-21 months' corrected age and a reduction of apnea. However, the data on cognition is hypothesis generating as it derives from a post hoc analysis from a single trial in 451 infants. Moreover, the data on apnea need confirmation in larger trials. The effect of adding data of cognitive 2-year outcomes of 1,744 infants from 2 RCT, which will be reported soon, should expand our understanding. This new data will need to be integrated with the older generation of RCTs but also with emerging suggestions from observational data on potential risks of blood transfusions. We discuss some of these warnings from observational studies. Finally, we ask whether we are ready to individualize blood transfusion to physiological measures made in individual infants, and we point to some current difficulties hindering this step.

Evaluation of serum ischemia-modified albumin levels in anemia of prematurity.

PURPOSE: Ischemia-modified albumin (IMA) is used to determine tissue hypoxia. We aimed to evaluate the serum IMA levels in preterm infants requiring transfusion due to anemia of prematurity, a clinical condition to cause tissue hypoxia. MATERIALS AND METHODS: This prospective study was performed in Etlik Zubeyde Hanim Hospital, Turkey. Preterm infants with birth weight less than 1500 g and born between 25 and 32 weeks were included during assessment for anemia of prematurity. The transfused infants with anemia of prematurity formed the "transfusion group", the control group consisted of gender, gestational and postnatal age-matched infants without transfusion requirement. Serum samples of control group and pre-transfusion and post-transfusion samples of transfusion group were analyzed for IMA (ABS unit). Serum IMA levels were compared between control group and pre-transfusion samples of transfusion group and were also evaluated for the significance of change after transfusion. RESULTS: Sixty-two infants were included (transfusion group: 31, control group: 31). The pretransfusion serum IMA levels were higher than that of infants in the control group [ABS unit; transfusion group; pre-transfusion: 1.00 (0.76-1.09) and control group: 0.81 (0.52?1.04); p = .03]. Serum IMA levels decreased significantly to 0.79 (0.59-0.95) after transfusion; p = .007. Infants with hematocrit higher than 30% had lower IMA levels [0.69 (0.54-0.96)] than infants with lower hematocrit [0.96 (0.75-1.05)]; p = .002. CONCLUSIONS: Clinicians may bear in mind that serum IMA levels could be utilized as a marker in deciding on erythrocyte transfusion in premature anemia.

Relationships between oxidative stress, haematology and iron profile in anaemic and non-anaemic calves.

The aim of this study was to investigate the relationships between oxidative stress, haematology and iron profile in neonatal dairy calves. Serum and haemolysate malondialdehyde (MDA), serum total antioxidant capacity, thiol groups, iron, total iron binding capacity, transferrin saturation and red blood cell (RBC) parameters were assessed in two groups: anaemic calves (n=14) and non-anaemic calves (n=16). Blood samples were collected from all of the calves within 24-48 hours after birth and at 7, 14, 21 and 28 days of age. A significant decrease in serum iron amount and transferrin saturation value (P<0.05) and a significant increase in haemolysate MDA concentration (P<0.05) in the anaemic calves were observed, when compared with non-anaemic calves. Total antioxidant capacity and thiol groups showed a significant positive correlation with iron profile and RBC parameters (haematocrit and haemoglobin) in the anaemic calves at day 21 (P<0.05). On the other hand, the concentration of haemolysate MDA was inversely correlated with the value of serum total antioxidant capacity (P<0.05). The results of the present study revealed that anaemic calves showed more severe oxidative stress than non-anaemic calves. In addition, iron insufficiency may be linked to the impairment of antioxidant defence system and oxidative damage of erythrocytes in the neonatal calves.

Newborn Thyroid Screening: Influence of Pre-Analytic Variables on Dried Blood Spot Thyrotropin Measurement.

BACKGROUND: Measuring thyrotropin (TSH) eluted from a dried blood spot (DBS) is used to screen an estimated 30 million newborns annually for congenital hypothyroidism (CH). Newborn thyroid screening has eliminated cretinism from the industrialized world and decreased the adverse effects of unrecognized CH on neurocognitive development. Hematocrit, a pre-analytic variable that affects the measurement of TSH from a DBS, contributes to the imprecision of DBS TSH measurement and could account for false-negative and false-positive DBS newborn screening test results. To assess whether variations in hematocrit found in newborns have a clinical effect in DBS-based newborn thyroid screening, the effects of hematocrit variability on the measurement of DBS TSH were studied. METHODS: U.S. Centers for Disease Control and Prevention procedures for manufacturing DBS performance testing standards were used to generate DBSs from blood samples, with hematocrits of 35%, 40%, 45%, 50%, 55%, 60%, and 65% and serum TSH concentrations of 6.3 ± 0.4 and 26.6 ± 8.0 mIU/L. TSH was measured in the eluates of four replicate DBS 3 mm punches at each hematocrit using the Thailand Ministry of Public Health Newborn Screening Operation Center enzyme-linked immunosorbent assay. Data were analyzed using a linear mixed-effects model. RESULTS: Based on the mixed-effects model, hematocrit significantly affected DBS TSH measurement (p < 0.001). A 1% increase in hematocrit resulted in a 0.06 mIU/L decrease in eluate TSH when TSH was 6.3 + 0.4 mIU/L, and a 0.21 mIU/L decrease in eluate TSH when TSH was 26.6 + 8.0 mIU/L. CONCLUSIONS: DBS TSH is significantly affected by the blood sample hematocrit. The pre-analytic variability due to hematocrit is independent of TSH assay sensitivity, specificity, precision, repeatability, and reference intervals. The effect of hematocrit on DBS TSH measurement is clinically relevant, could account for geographic and ethnic variation in the incidence of CH, and may result in both false-positive and false-negative CH screening results. Individual newborn and population-specific hematocrit correction factors may improve the precision of DBS TSH measurement.

Multiple red blood cell transfusions and iron overload in very low birthweight infants.

BACKGROUND AND OBJECTIVES: To estimate the risk of iron overload in very low birthweight (VLBW) infants who receive more than two red blood cell (RBC) transfusions, in comparison with those who receive two or less during their hospital stay. MATERIALS AND METHODS: Prospective open cohort study in VLBW infants with >2 (exposed) and ≤2 (non-exposed) RBC transfusions. Ferritin, alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were measured at birth and after each RBC transfusion. The incidence of iron overload was determined. Risk factors were analysed using a logistic regression model. RBC transfusion volume correlations with ferritin, ALT and AST were calculated with Spearman's rank correlation coefficient, as well as correlations between ferritin and aminotransferases. RESULTS: A total of 63 patients were enrolled, 18 of which were exposed and 45 non-exposed. Twelve patients developed severe iron overload, eight exposed (44·5%) vs. four (8·8%) non-exposed (RR: 5, 95% CI: 1·7-14·6). Multivariate analysis showed that the number of transfusions increased the risk of iron overload (OR: 2·07, 95% CI: 1·36-2·14) while a higher one-minute Apgar score was associated with a lower risk (OR: 0·56, 95% CI: 0·32-0·99). Severe iron overload mainly occurred with a transfusion volume higher than 120 ml/kg. There was a positive correlation between ferritin and transfusion (r = 0·53; P < 0·001). CONCLUSION: There was a higher risk of iron overload in exposed infants in comparison with non-exposed infants. Severe iron overload in VLBW infants may occur with a total transfusion volume >120 ml/kg.

Foetal haemoglobin, blood transfusion, and retinopathy of prematurity in very preterm infants: a pilot prospective cohort study.

PurposeTo identify if there is an association between foetal haemoglobin (HbF) concentration and retinopathy of prematurity (ROP) in very preterm infants.Patients and methodsProspective cohort study. Infants born <32 weeks' gestational age or <1501 g in two tertiary neonatal units between January 2012 and May 2013 (n=42) were enrolled. HbF and adult haemoglobin (HbA) concentrations were measured using high-pressure liquid chromatography from blood samples sent as part of routine neonatal care once routinely requested laboratory tests had been performed. Clinical data were obtained from case notes. We calculated odds ratios (ORs) (95% confidence intervals (CIs)) to quantify the relationship between initial and mean %HbF with ROP severity (none, stages 1-3).ResultsA total of 42 infants were recruited: mean gestation 28.0 weeks (SD 1.91); mean birth weight 1042 g (SD 264). Six infants died before ROP screening; 14/36 developed ROP (39%); and 22/36 (61%) did not. Infants who developed ROP had similar initial %HbF (83.3 vs 92.3%, P=0.06), but significantly lower mean %HbF (61.75 vs 91.9%, P=0.0001) during their inpatient stay than those who did not develop ROP. In ordinal logistic regression models adjusted for birth weight, gestation and transfusion volume, mean post-natal %HbF was negatively associated with ROP severity: adjusted OR 0.94 (0.90-0.99), while initial %HbF at birth was not: adjusted OR 1.05 (0.97-1.16).ConclusionReplacing HbF by HbA during transfusion may promote ROP development by rapidly increasing oxygen availability to the retina. Conversely, maintaining a higher %HbF may be a protective factor against ROP.

Neomorphic effects of the neonatal anemia (Nan-Eklf) mutation contribute to deficits throughout development.

Transcription factor control of cell-specific downstream targets can be significantly altered when the controlling factor is mutated. We show that the semi-dominant neonatal anemia (Nan) mutation in the EKLF/KLF1 transcription factor leads to ectopic expression of proteins that are not normally expressed in the red blood cell, leading to systemic effects that exacerbate the intrinsic anemia in the adult and alter correct development in the early embryo. Even when expressed as a heterozygote, the Nan-EKLF protein accomplishes this by direct binding and aberrant activation of genes encoding secreted factors that exert a negative effect on erythropoiesis and iron use. Our data form the basis for a novel mechanism of physiological deficiency that is relevant to human dyserythropoietic anemia and likely other disease states.

Iron homeostasis after blood transfusion in stable preterm infants - an observational study.

AIM: To evaluate the short-term effects of blood transfusion on iron status [hemoglobin, ferritin, soluble transferrin receptor (sTfR), and reticulocyte count], hepcidin, and erythropoietin in stable preterm infants. METHOD: Sixty-three preterm infants treated with red blood cell transfusions (RBCTs) were included. Venous blood samples were collected before and within 24 h after each transfusion. RESULTS: Hemoglobin concentration increased after RBCT (7.2±1.2 g/dL vs. 13.7±2.3 g/dL, P=0.02), as well as ferritin [131 (63-110.4) ng/mL vs. 211 (125.7-299.2) ng/mL, P=0.05); reticulocyte count decreased. sTfR did not change. Hepcidin serum levels increased from 37.5 (21.3-84.7) ng/mL to 72.6 (31.3-126.2) ng/mL, (P=0.04) and erythropoietin decreased (48±19 pg/mL vs. 29±17 pg/mL, P=0.06) after RBCT. A positive linear correlation was found (R2=0.76, P=0.0001) between hepcidin and ferritin levels of post-minus-pre RBCT. Hepcidin levels increased significantly in preterm infants who received RBCT after 1 month of age compared to those who received RBCT at <1 month (P=0.03). No correlation was found between gestational age, weight appropriate for age, or length of blood storage and hepcidin levels. CONCLUSION: Preterm infants can control iron levels by regulating hepcidin and decreasing erythropoietin. This ability varies with postnatal age.