Preterm neonates benefit from low prophylactic platelet transfusion threshold despite varying risk of bleeding or death.

The Platelets for Neonatal Thrombocytopenia (PlaNeT-2) trial reported an unexpected overall benefit of a prophylactic platelet transfusion threshold of 25 × 109/L compared with 50 × 109/L for major bleeding and/or mortality in preterm neonates (7% absolute-risk reduction). However, some neonates in the trial may have experienced little benefit or even harm from the 25 × 109/L threshold. We wanted to assess this heterogeneity of treatment effect in the PlaNet-2 trial, to investigate whether all preterm neonates benefit from the low threshold. We developed a multivariate logistic regression model in the PlaNet-2 data to predict baseline risk of major bleeding and/or mortality for all 653 neonates. We then ranked the neonates based on their predicted baseline risk and categorized them into 4 risk quartiles. Within these quartiles, we assessed absolute-risk difference between the 50 × 109/L- and 25 × 109/L-threshold groups. A total of 146 neonates died or developed major bleeding. The internally validated C-statistic of the model was 0.63 (95% confidence interval, 0.58-0.68). The 25 × 109/L threshold was associated with absolute-risk reduction in all risk groups, varying from 4.9% in the lowest risk group to 12.3% in the highest risk group. These results suggest that a 25 × 109/L prophylactic platelet count threshold can be adopted in all preterm neonates, irrespective of predicted baseline outcome risk. Future studies are needed to improve the predictive accuracy of the baseline risk model. This trial was registered at www.isrctn.com as #ISRCTN87736839.

Postnatal intervention for the treatment of FNAIT: a systematic review.

OBJECTIVE: Fetal and neonatal alloimmune thrombocytopenia (FNAIT) is associated with life-threatening bleeding. This systematic review of postnatal management of FNAIT examined transfusion of human platelet antigen (HPA) selected or unselected platelets, and/or IVIg on platelet increments, hemorrhage and mortality. STUDY DESIGN: MEDLINE, EMBASE and Cochrane searches were conducted until 11 May 2018. RESULT: Of 754 neonates, 382 received platelet transfusions (51%). HPA-selected platelets resulted in higher platelet increments and longer response times than HPA-unselected platelets. However, unselected platelets generally led to sufficient platelet increments to 30 × 109/L, a level above which intracranial hemorrhage or other life-threatening bleeding rarely occurred. Platelet increments were not improved with the addition of IVIg to platelet transfusion. CONCLUSION: Overall, HPA-selected platelet transfusions were more effective than HPA-unselected platelets but unselected platelets were often effective enough to achieve clinical goals. Available studies do not clearly demonstrate a benefit for addition of IVIg to platelet transfusion.

A Prospective Study on the Incidence and Outcomes of Neonatal Thrombocytopenia at a Tertiary Care Facility in Central Saudi Arabia.

BACKGROUND: The incidence of neonatal thrombocytopenia is low, yet highly dependent on the populations studied. PURPOSE: To assess the incidence of neonatal thrombocytopenia and identify factors associated with its outcomes, namely time to disease onset, recovery duration, and platelet count. METHODS: A prospective observational study was conducted between May and October 2013 at a large tertiary care facility in Saudi Arabia. Neonates with a platelet count of fewer than 150,000/µL of blood were followed up until their recovery or death. RESULTS: The period incidence of neonatal thrombocytopenia was 84/4379 (1.9%). The mortality rate associated with the condition was 68/100,000 births. The male-female ratio of neonates with thrombocytopenia was 2.4:1. The mean (standard deviation) time to disease onset was 1.83 (1.29) days, whereas that of recovery duration was 15.35 (18.46) days. The mean (standard deviation) platelet count at onset was 109,543 (32,826)/µL of blood, whereas that of the increase in platelet count from onset to recovery was 121,876 (78,218)/µL of blood. Treatment comprised monitoring/spontaneous recovery (n = 52, 64.2%) or platelet transfusion (n = 9, 11.1%), immunoglobulins (n = 8, 9.9%), or a combination of both (n = 12, 14.8%). Neonates with a higher gestational age (ß = 8061, t = 2.456) and late disease onset (ß = 26,178, t = 3.969) were more likely to have a larger increase in platelet count from onset to recovery than those with a lower gestational age (adjusted P = .017) and earlier disease onset (adjusted P < .001). IMPLICATIONS: The high incidence of neonatal thrombocytopenia in this Middle Eastern setting indicates that it may be dependent on the population studied. Special attention should be focused on neonates of lower gestational ages and with an early disease onset, because their platelet count recovery may be slower than that of the countergroup.

Neonatal thrombocytopenia-causes and outcomes following platelet transfusions.

We evaluated the causes for neonatal thrombocytopenia (NT), the duration of NT, and the indications of platelet transfusions (PT) by means of a retrospective cohort study over a 23-year period. Neonates with NT were identified via ICD-10 code D69.6. Of 371 neonates (1.8/1000 live births) with NT, the majority (312; 84.1%) had early onset thrombocytopenia, and 282 (76%) were preterm born. The most frequent causes for NT were early and late onset sepsis and asphyxia. The mean duration of thrombocytopenia was 10.2 days and was negatively correlated (KK = - 0.35) with the number of PT. PT were given to 78 (21%) neonates, 38 (49%) of whom had very severe NT. The duration of NT was positively related to the severity of NT and the number of subsequent PT. A mortality rate of 10.8% was significantly associated with bleeding signs (p < 0.05) and correlated with increasing number of PT (p < 0.05) but not with the severity of NT (p = 0.4). In the case of relevant hemorrhage, PT did not influence the mortality rate (p = 0.09). All deaths followed neonatal sepsis. CONCLUSIONS: Prematurity and diagnoses including early and late onset sepsis and asphyxia were the most common causes of NT. Mortality was not associated with the severity of NT but increased with the number of PT. What is Known: • The causes for neonatal thrombocytopenia (NT) are well known. • The effects of platelet transfusions (PT) and its indications are still a matter of debate and recommendations differ widely. What is New: • The duration of NT is positively related to the severity of NT and the number of subsequent PT. • The mortality rate is not associated with the severity of NT but increases with increasing numbers of PT and in the case of relevant intraventricular hemorrhage (≥ grade II), PT does not influence the mortality rate.

Platelets for neonatal transfusion - study 2: a randomised controlled trial to compare two different platelet count thresholds for prophylactic platelet transfusion to preterm neonates.

INTRODUCTION: Neonatal thrombocytopenia is a common and important clinical problem in preterm neonates. A trial assessing clinically relevant outcomes in relation to the different platelet count thresholds used to trigger transfusion has never been undertaken in preterm neonates with severe thrombocytopenia. OBJECTIVES: Platelets for Neonatal Transfusion - Study 2 (PlaNeT-2) aims to assess whether a higher prophylactic platelet transfusion threshold is superior to the lower thresholds in current standard practice in reducing the proportion of patients who have a major bleed or die up to study day 28. METHODS: PlaNeT-2 is a two-stage, randomised, parallel-group, superiority trial. PlaNet-2 compares clinical outcomes in preterm neonates (<34 weeks' gestation at birth) randomised to receive prophylactic platelet transfusions to maintain platelet counts at or above either 25 × 10(9)/l or 50 × 10(9)/l. The primary outcome measure is the proportion of patients who either die or experience a major bleed up to and including study day 28. A total of 660 infants will be randomised. RESULTS AND CONCLUSIONS: This trial will help define optimal platelet transfusion support for severely thrombocytopenic preterm neonates by evaluating the risks and benefits of two different prophylactic neonatal platelet transfusion thresholds.

Delayed diagnosis of fetal and neonatal alloimmune thrombocytopenia: a cause of perinatal mortality and morbidity.

OBJECTIVE: To evaluate the rate and consequences of a late or missed diagnosis of fetal and neonatal alloimmune thrombocytopenia (FNAIT). DESIGN: Retrospective analysis of prospectively collected data of a national cohort. SETTING: National referral centre for fetal therapy in the Netherlands. POPULATION: Twenty-six women with pregnancies complicated by FNAIT and at least one previous pregnancy with a thrombocytopenic child. METHODS: Retrospective analysis of data from our electronic FNAIT database. In a consecutive cohort managed between July 2008 and July 2010, timing of first diagnosis of FNAIT was correlated to severity and outcome in the subsequent pregnancies. MAIN OUTCOME MEASURES: Occurrence of delayed diagnosis of FNAIT, and possibly associated intracranial haemorrhage (ICH). RESULTS: In four of 26 pregnancies, timely diagnostic testing for FNAIT was not performed despite fetal or neonatal thrombocytopenia or ICH. Down syndrome, dysmaturity and birth trauma were perceived to be the cause of the thrombocytopenia/ICH. In two of these four subsequent, untreated pregnancies, severe fetal ICH occurred. The other 22 women were treated for FNAIT using intravenous immunoglobulin, all children are alive and well. CONCLUSIONS: All neonates with thrombocytopenia at birth should be evaluated for FNAIT. Missing this diagnosis can have severe consequences for subsequent pregnancies.

[Fetal and neonatal alloimmune thrombocytopenia]. / Føtal og neonatal alloimmun trombocytopeni er en mulig fatal tilstand.

Fetal and neonatal alloimmune thrombocytopenia (FNAIT) may lead to intracranial haemorrhage (ICH) resulting in neurological damage or death. In FNAIT, transplacental maternal antibodies cause destruction of fetal platelets. Maternal immunisation occurs to fetal human platelet antigens (HPAs) inherited from the father. In the absence of screening the diagnosis often relies on a serious incident in a previous pregnancy or in a newborn sibling. Thus, a future reduction in the risk of ICH depends on prospective large trials to evaluate different diagnostic, treatment, and prevention strategies.

Severe Thrombocytopenia in the NICU.

OBJECTIVE: Severe thrombocytopenia (platelets

Prospective, observational study of outcomes in neonates with severe thrombocytopenia.

OBJECTIVE: A cross-sectional, observational study of outcomes for neonates with severe neonatal thrombocytopenia (SNT; platelet count of <60 x 10(9) platelets per L) was performed to examine hemorrhage and use of platelet transfusions. METHODS: Neonates who were admitted to 7 NICUs and developed SNT were enrolled for daily data collection. RESULTS: Among 3652 neonatal admissions, 194 neonates (5%) developed SNT. The median gestational age of 169 enrolled neonates was 27 weeks (interquartile range [IQR]: 24-32 weeks), and the median birth weight was 822 g (IQR: 670-1300 g). Platelet count nadirs were <20 x 10(9), 20 to 39 x 10(9), and 40 to 59 x 10(9) platelets per L for 58 (34%), 64 (39%), and 47 (28%) of all enrolled infants, respectively. During the study, 31 infants (18%) had no recorded hemorrhage, 123 (73%) developed minor hemorrhage, and 15 (9%) developed major hemorrhage. Thirteen (87%) of 15 episodes of major hemorrhage occurred in neonates with gestational ages of <28 weeks. Platelet transfusions (n = 415) were administered to 116 infants (69%); for 338 (81%) transfusions, the main recorded reason was low platelet count. Transfusions increased the platelet count from a median of 27 x 10(9) platelets per L (IQR: 19-36 x 10(9) platelets per L) to 79 x 10(9) platelets per L (IQR: 47.5-127 x 10(9) platelets per L). CONCLUSIONS: Although one third of neonates enrolled in this study developed thrombocytopenia of <20 x 10(9) platelets per L, 91% did not develop major hemorrhage. Most platelet transfusions were given to neonates with thrombocytopenia with no bleeding or minor bleeding only.

Do platelet transfusions in the NICU adversely affect survival? Analysis of 1600 thrombocytopenic neonates in a multihospital healthcare system.

OBJECTIVE: Several studies have indicated a correlation between the number of platelet transfusions received by newborn intensive care unit (NICU) patients and the mortality rate. The number of platelet transfusions might be a marker for level of illness, and thus predictive of mortality. However, an alternative hypothesis is that multiple platelet transfusions themselves are harmful in this population. STUDY DESIGN: We evaluated data from all thrombocytopenic neonates cared for in the Intermountain Healthcare NICUs in the past 4 years, seeking associations between the lowest platelet count recorded, number of platelet transfusions received and mortality rate. We also conducted a sensitivity analysis to examine the hypothesis that platelet transfusions were responsible for some fraction of the mortality rate. RESULT: Transfusion and outcome data were examined from 1600 thrombocytopenic NICU patients. At any level of platelet count, some patients received platelet transfusions but others did not. However, at all levels of platelet count, those that received platelet transfusions had a higher mortality rate. Neonates not given any platelet transfusions had a mortality rate of 2%, those with 1 or 2 transfusions had a mortality rate of 11% (P<0.001); those with >10 had a mortality rate of 35% (P<0.001); and those with > or = 20 had a mortality rate of 50% (P<0.001). A sensitivity analysis suggested that the platelet transfusions themselves were very likely responsible for some fraction of the increasing mortality rate. CONCLUSION: The number of platelet transfusions administered in the NICU predicts the mortality rate. Some of this correlation is ascribable to unknown and unmeasured factors such as level of illness. However, the present data and the sensitivity analysis both suggest that some of this correlation is due to harmful effects of multiple platelet transfusions in this group of patients.