Neonatal thrombocytopenia: causes and management

Prognostic significance of early platelet count decline in preterm newborns

OBJECTIVES

Decline of platelets with or without thrombocytopenia is observed in critically ill preterm newborns. Prognostic significance of platelets count in Neonatal Intensive Care Unit focused on outcome after thrombocytopenia. We aimed to estimate the changes in platelets count within the first 7 days of life in preterm newborns and its relation to final outcomes.

METHODS

Retrospectively, the platelets count during the first 7 days of life, and its association with mortality, length of stay among survivors (LOS), and later severe morbidities were determined. Appropriate regression analyses were used to examine possible relations between studied variables.

RESULTS AND DISCUSSION

Platelets drop that did not reach thrombocytopenia level in the first 7 days of life happened in 61.7%. Platelets count drop in the first 7 days of life was a predictor of mortality, LOS, and major morbidities such as intraventricular hemorrhage and necrotizing enterocolitis.

CONCLUSIONS

Platelets count drop within the first 7 days of life independent of thrombocytopenia can be used to predict increased mortality, LOS, and the development of later severe morbidities in critically ill preterm neonates.

Mouse prenatal platelet-forming lineages share a core transcriptional program but divergent dependence on MPL

Prenatal platelet-forming lineages are subject to common transcription factor controls despite distinct spatial and ancestral origins. Platelet-forming lineage production is MPL-independent on emergence, but MPL is required in the late fetus for efficient thrombopoiesis.

Macrophage activation syndrome in a newborn infant born to a mother with autoimmune disease

Macrophage activation syndrome (MAS) is a complication of rheumatic disorders characterized by cytopenia, multiple organ dysfunction and coagulopathy associated with an inappropriate activation of macrophage. In neonatal lupus erythematosus, MAS is rare but fatal, requiring early diagnosis and treatment for optimal outcome. We report a case of MAS in a neonate born to a mother with autoimmune disease, improved by treatment with steroid, intravenous immunoglobulin and cyclosporine.

Neonatal thrombocytopenia and platelet transfusion - a UK perspective

Five percent of newborn infants admitted to UK neonatal units during a recent study developed a platelet count <60 × 10(9)/l, and 60% of these were transfused platelets. This review summarises the common causes and mechanisms of thrombocytopenia in the newborn. Relevant evidence relating the platelet count to the risk of haemorrhage is reviewed, and current UK guidance on transfusion thresholds outlined. The UK policy for the provision of platelets for transfusion to neonates is described, including the particular requirements for neonatal allo-immune thrombocytopenia. Finally, we look towards the future and prospects for reducing the need to expose newborns to donor-derived platelets.

Placental pathology and neonatal thrombocytopenia: lesion type is associated with increased risk

OBJECTIVE

To investigate the association between thrombocytopenia and placental lesions.

STUDY DESIGN

Cases included singleton infants admitted to the intensive care unit (2005 to 2010) with platelet counts <100 000 μl(-1). We selected a contemporaneous control group matched for gestational age: 49 cases and 63 controls. The frequency of thrombosis in fetal vessels, fetal thrombotic vasculopathy, acute chorioamnionitis, chronic villitis, infarcts, hematomas, cord insertion and increased circulating nucleated red blood cells were identified on retrospective review of placental histology. Logistic regression models were used to test for associations.

RESULT

Placental lesions associated with poor maternal perfusion (odds ratio (OR) 3.36, 95% confidence interval (CI) 1.38, 8.15) or affecting fetal vasculature (OR 2.75, 95% CI 1.05, 7.23), but not inflammation, were associated with thrombocytopenia. A Pearson Chi-Square Test for Independence for fetal and maternal lesions indicated that the two are independent factors.

CONCLUSION

Poor maternal perfusion and fetal vascular lesions are independently associated with thrombocytopenia in the newborn.

Mean platelet volume and uric acid levels in neonatal sepsis

OBJECTIVES

To determine the role of mean platelet volume (MPV) and uric acid levels in the diagnosis of neonatal sepsis (NS).

METHODS

A total of 146 newborns with suspected NS were prospectively included in the study and infants without NS (n = 142) were assigned as controls. The patients were divided into three groups: Group I (n = 64): clinical NS, Group II (n = 82): culture-proven NS, and Group III (n = 142): healthy controls.

RESULTS

The patients in Group II had the highest C-reactive protein (CRP) levels (54.6 ± 5.4 mg/L), lowest platelet counts (199,329 ± 135,952/mm(3)) and lowest uric acid levels (2.6 ± 1.8 mg/dL) when compared to Groups I and III (p < 0.05, for all comparisons). MPV values were higher in Group I (10.6 ± 1.1 fL) and Group II (10.4 ± 0.9 fL) when compared to Group III (9.2 ± 1.2 fL) (p = 0.001), although there was no difference between Groups I and II. Area under curve (AUC) values for CRP, MPV, and uric acid were 0.92 (p = 0.001), 0.76 (p = 0.001) and 0.28 (p = 0.001), respectively. The diagnostic cut-off values for CRP and MPV were 9.5 mg/dL and 10.4 fL. Sensitivity and specificity of MPV in NS were 54 % and 82 % respectively. When combined with CRP its sensitivity and specificity increased to 89 % and 79 % respectively.

CONCLUSIONS

The combined use of CRP and MPV should be considered in the early diagnosis of NS, but uric acid levels may only be utilized as an additional tool to support diagnosis. CRP is shown to be more sensitive and specific than MPV and uric acid in diagnosing neonatal sepsis.

Clinical significance of platelet-associated hematological parameters as an early supplementary diagnostic tool for sepsis in thrombocytopenic very-low-birth-weight infants

Sepsis is an important cause of death in very-low-birth-weight (VLBW) neonates. Although conventional diagnostic indicator of sepsis has been done by blood cultures, this took much longer time. The measurement of platelet-associated parameters such as mean platelet volume (MPV) and platelet distribution width (PDW) become more reliable and accurate parameters as a non-specific marker for sepsis. Our objective is to examine the usefulness of those platelet hematological parameters as a supplementary diagnostic tool for sepsis in VLBW infants. This study is a retrospective cohort study of neonates subject to the diagnosis of sepsis from October 2006 to July 2010. This study was conducted at Korea University medical center. We studied total 2,336 infants for 32 days from birth (Day 0) to Day 31. We compared three groups of infants to examine differences of platelet parameters according to their age from birth to Day 31: (i) full-terms versus VLBW without sepsis, (ii) VLBW without sepsis versus VLBW with sepsis and (iii) thrombocytopenic VLBW without sepsis versus those with sepsis. The platelet-associated parameters were significantly distinguishable between septic and non-septic groups at their early age (∼ 1 week), especially platelet counts (PLT) (p = 0.0091), MPV (p = 0.007) and PDW (p = 0.0372) in thrombocytopenic VLBW infants. The decreased PLT, elevated MPV and PDW were major characteristics of septic group. We suggested maximum cutoff values of the platelet factors by performing receiver operating characteristic curve analysis between septic and non-septic thrombocytopenic VLBW infants, among which MPV was the most promising index (AUCMPV = 0.7044 > AUCPLT = 0.6921 > AUCPDW = 0.6593). Platelet-associated hematological parameters are useful for the early diagnosis of sepsis as a more efficient and supplementary diagnostic method in thrombocytopenic VLBW infants.

Evaluation and management of thrombocytopenic neonates in the intensive care unit

Thrombocytopenia is a very frequent problem among sick neonates, affecting up to 35% of all infants admitted to the neonatal intensive care unit (NICU), and serves as an important indicator of multiple clinical conditions. The cause of the thrombocytopenia is unclear in up to 60% of affected neonates. A clinical classification of thrombocytopenia is based on the time of presentation, early (≤72 hours of life) vs. late (>72 hours of life). Early thrombocytopenia is commonly associated with feto-maternal conditions, is most commonly caused by disorders associated with placental insufficiency, and is generally mild to moderate and resolves spontaneously within 7-10 days without any intervention. In contrast, neonates who develop late-onset thrombocytopenia frequently have bacterial sepsis or necrotizing enterocolitis. It is often severe (platelets <50,000/μL), prolonged and frequently requires multiple platelet transfusions. Platelet transfusions represent the only specific therapy currently available for most thrombocytopenic neonates, even though much evidence suggests that platelet transfusions are not benign. Many of the prophylactic platelet transfusions currently given to NICU patients are unnecessary, convey no benefits, and carry known and unknown risks. For this reason, pharmacological alternatives have been investigated as potential therapies for thrombocytopenia, but they still have limited use treating the common varieties of neonatal thrombocytopenia.

Infection-immunity liaison: pathogen-driven autoimmune-mimicry (PDAIM)

Autoimmunity causes pathological conditions resulting in autoimmune diseases (ADs). Although autoimmunity is a mystery, immunological dogma suggests that autoreactive cell reactivation (ACR) breaks self-tolerance and induces autoimmunity. Thus, ACR is a royal pathway for ADs. Cumulative evidence implicates environmental factors as secondary triggers of ADs in the genetically susceptible hosts. Infection is the most likely trigger. Although several mechanisms have been proposed to explain how infectious agents trigger ADs, ACR is assumed to be an essential pathway. Here, by showing some exemplary ADs, we propose two novel pathways, "molecular modification pathway" and "hyper-immune-inflammatory response pathway", which induce AD-like conditions directly by infectious agents without ACR. These AD-like conditions are actually not true "ADs" according to the current definition. Therefore, we define them as "pathogen-driven autoimmune-mimicry (PDAIM)". Confirming PDAIM will open perspectives in developing novel fundamental and non-immunosuppressive therapies for ADs. The idea should also provide novel insights into both the mechanisms of autoimmunity and the pathogenesis of ADs.

[Thrombopenia and the nature of the microorganism in infected critically ill children]

BACKGROUND

Thrombopenia is correlated with sepsis and mortality in pediatric intensive care units. The purpose of this study was to find an association between thrombopenia and the microorganism type to guide the choice of empiric antibiotic therapy in infected critically ill children.

MATERIALS AND METHODS

We conducted a prospective descriptive study, including all newborns, infants, and children admitted to a pediatric surgical intensive care unit from 1st January to 31st December 2009. We identified patients who developed an infection and/or thrombopenia (platelet count less than 100,000/mm(3)) during hospitalization.

RESULTS

One hundred ninety-seven patients were included (57 newborns, 41 infants, 99 children). Ninety patients developed 100 infectious episodes during the study period. Of the 57 newborns enrolled in the study, 31 (54%) developed 37 infections. Seventy-six microorganisms (55 Gram-negative bacilli [GNB], 17 Gram-positive cocci, two Gram-negative cocci, two fungal pathogens) were identified during 65 infectious episodes in 55 patients. Thirty-four episodes of thrombopenia were observed in 30 patients. Thrombopenia was observed only in infected patients (P<0.001). Thrombopenia was associated with infections caused by GNB (26/28 vs 20/37, P=0.001) and by Klebsiella (16/28 vs 6/37, P=0.001) and may be associated with infections caused by GNB producing extended-spectrum beta-lactamases (P=0.07). Gram-positive cocci infections were correlated to the non-occurrence of thrombopenia (P=0.02). Postoperative peritonitis was also significantly associated with thrombopenia (P=0.03). The mortality rate in our patients was 12.7% (22.8% in neonates). There was an association between thrombopenia and death in univariate analysis (11/25 vs 19/172, P<0.001). Multivariate logistic regression analysis did not confirm thrombopenia as an independent predictive factor of mortality in children.

CONCLUSION

Because of the relatively high proportion of resistant GNB, an empiric antibiotic therapy combining a carbapenem and an aminoglycoside may be indicated in infected critically ill children developing thrombopenia.

A rare manifestation of neonatal alloimmune thrombocytopaenia

Neonatal alloimmune thrombocytopaenia (NAIT) results from a fetomaternal incompatibility with maternal sensitisation against a fetal human platelet antigen (HPA) and antibodies transfer to the fetal circulation, leading to platelet destruction. The clinical presentation is variable and isolated intraocular haemorrhage is rare. We present the case of a male newborn, with intrauterine growth restriction, born at 29 weeks due to pre-eclampsia. He presented proptosis of the left eye, hyphaema and elevated intraocular pressure, with no other signs of haemorrhage. Severe thrombocytopaenia was found (27×10(9)/L). Perinatal infection and maternal thrombocytopaenia were excluded. Positive anti-HPA-1a and antihuman leucocyte antigen class I alloantibodies were found in the mother. Platelet crossmatch between the father's platelets and mother's plasma was positive. Platelet transfusions and intravenous immunoglobulin were given with favourable response. This case highlights an unusual presentation of NAIT, which should be suspected in the presence of severe thrombocytopaenia in the first 24-72 h of life.

Hematological complications of neonatal lupus: case report and review of the literature

Neonatal thrombocytopenia is a common clinical problem and may be a result of maternal and/or fetal conditions. We present a young patient with thrombocytopenia as a result of neonatal lupus, a passively acquired autoimmune disease. The diagnosis was suspected on the basis of the presence of a facial rash. This case highlights the characteristic eruption of neonatal lupus and an underappreciated cause of neonatal thrombocytopenia for the pediatric hematologist. We also review the hematological complications of neonatal lupus.

A randomized trial of platelet transfusions over 30 vs 120 minutes: is there an effect on post-transfusion platelet counts?

OBJECTIVE

To determine whether platelet infusion time affects platelet counts in thrombocytopenic newborns.

STUDY DESIGN

This was a prospective randomized control study of 43 platelet transfusions given to newborns. Transfusions were randomized to run over either 30 min or 2 h. Platelet counts taken 30 min and 6 h after transfusion were compared using parametric, nonparametric, Pearson's correlation and logistic regression.

RESULT

Changes in platelet counts 30 min and 6 h after transfusion were not different between the groups. Weak but significant negative correlations existed between postmenstrual age and change in platelet count at 30 min (r=-0.33, P=0.04) and 6 h (r=-0.37, P=0.018) after transfusion. There were no differences between the mean blood pressures before and after transfusion in either group.

CONCLUSION

Transfusion duration does not affect post-transfusion platelet counts in newborns. Babies of lower postmenstrual age (PMA) may have better responses to platelet transfusions. Finally, platelet transfusions over both durations are well tolerated in neonates.

Upper GI bleeding among neonates admitted to Mulago Hospital, Kampala, Uganda: a prospective cohort study

BACKGROUND

The World Health Organization (WHO) reports estimate that 85% of newborn deaths are due to infections, prematurity and fetal distress. These conditions are risk factors for upper GI bleeding (UGIB) in sick neonates. UGIB is associated with poor neonatal outcomes such as prolonged hospitalisation and poor weight gain. The magnitude of UGIB and its contribution to neonatal morbidity has not been described in most low income countries.

OBJECTIVE

To determine the occurrence and factors associated with UGIB among neonates admitted to the Special Care Unit (SCU) of Mulago Hospital.

METHODS

This was a prospective single cohort study where neonates admitted within 24 hours of birth were consecutively enrolled and followed up for seven days. Gastric aspirates from the neonates were examined daily over a period of 7 days using Guaiac and Apt tests for evidence of UGIB. Data on occurrence of UGIB has been presented as proportions and Odds Ratios for associated factors.

RESULTS

Out of 191 neonates, 44 (23 %) developed UGIB. Factors independently associated with UGIB included cyanosis in the neonate [OR 5.8; (95% CI; 1.8 - 19.1) p-value 0.004], neonatal seizures [OR 12.6; (95% CI 2.3 - 70.5); p-value 0.004] and birth asphyxia [OR 6.3; (95% CI 1.9 - 21.6); p-value 0.003].

CONCLUSIONS

In the first seven days of life, UGIB occurred in 1:4 neonates. Factors independently associated with UGIB included birth asphyxia, cyanosis in the neonate and neonatal seizures.

Neonatal lupus complicated by hemorrhagic stroke

Neonatal lupus is a passively acquired autoimmune syndrome resulting from the transplacental passage of maternal anti-Ro/SSA and/or anti-La/SSB antibodies to the fetus. Few past studies have reported central nervous system involvement in neonatal lupus, and most cases had a good neurological outcome. We report here a preterm case of neonatal lupus with thrombocytopenia and comorbid hemorrhagic stroke. In the follow-up, the infant developed spastic quadriplegia and showed delayed milestones. We believe that this is the first reported case of neonatal lupus accompanied by perinatal hemorrhagic stroke. We present this case to remind clinicians to conduct regular central nervous system surveys in cases of neonatal lupus.

In vivo effect of recombinant human granulocyte colony-stimulating factor on neutrophilic expression of CD11b in septic neonates: a randomized controlled trial

Neonates are susceptible to septicemia secondary to quantitative and qualitative neutrophilic defects. Granulocyte colony-stimulating factor (G-CSF) stimulates myeloid progenitor cell proliferation and induces selective neutrophil functions. The authors aimed to evaluate the effect of G-CSF administration in septic neonates on neutrophil production and CD11b expression. Sixty septic neonates were randomized to receive intravenous G-CSF 10 μg/kg/day for 3 days (G-CSF group, n = 30), or not to receive G-CSF (non-G-CSF group, n = 30). Thirty healthy newborns were included as controls. Laboratory investigations included complete blood count, C-reactive protein, blood culture, renal and liver function tests, and assessment of neutrophilic expression of CD11b. Total leukocytes count (TLC), absolute neutrophil count (ANC), and immature myeloid cell count in G-CSF group showed significant difference between post-and pre-G-CSF levels. TLC, ANC, immature myeloid cell count and immature/total myeloid cells ratio were higher in G-CSF group compared to non-G-CSF group on days 1 and 3. Higher neutrophilic expression of CD11b was reported in both septic groups on day 0 compared to control group. On day 5, CD11b was higher in G-CSF group than non-G-CSF group. G-CSF improved CD11b% in neutropenic and non-neutropenic septic neonates. No significant difference was found between pre- and posttreatment renal and liver function tests. Lower duration of antibiotic intake and hospitalization was observed in G-CSF group compared to non-G-CSF group. G-CSF administration as an adjuvant therapy for neonatal septicemia, whether neutropenic or not, improves neutrophilic count and function and contributed to early healing from sepsis.

Is a small platelet mass associated with intraventricular hemorrhage in very low-birth-weight infants?

OBJECTIVE

We sought to determine whether, among very low-birth-weight (VLBW) neonates, the platelet mass was associated with common perinatal factors, and whether a low platelet mass in the first days following birth was associated with a higher incidence and/or severity of intraventricular hemorrhage (IVH).

STUDY DESIGN

This was a cross-sectional, retrospective cohort analysis of VLBW infants admitted to a level 3 neonatal intensive care unit from June 2003 to July 2006, n=408. Platelet mass was calculated and recorded on the day of birth and for 2 consecutive days thereafter. All neonates had a screening cranial sonogram on day 4 of life. Statistical analysis included analysis of variance and Mann-Whitney U-test.

RESULT

Neonates born to mothers with pre-eclampsia had a smaller platelet mass (1921 fl/nl ± 603 vs 2297 fl/nl ± 747; P<0.01). The same was found among neonates with intrauterine growth restriction (IUGR). In contrast, neonates born after histological chorioamnionitis had a larger platelet mass (2400 fl/nl ± 749 vs 2036 fl/nl ± 674; P<0.01). No effect of platelet mass, measured on the day of birth, was observed related the outcomes of IVH, severe IVH or death. However, those with a platelet mass <10th percentile on the 2 subsequent days following birth were more likely to have severe IVH or death.

CONCLUSION

Among VLBW neonates, pre-eclampsia and IUGR are associated with a lower platelet mass, owing to their effect on platelet count. Histological chorioamnionits is associated with a larger platelet mass. A mass <10th percentile on the days following birth was associated with severe IVH and/or death, but it remains unclear whether this is a cause of, or an effect of, the IVH.

Incidence of thrombocytopenia in the neonatal intensive care unit

BACKGROUND

Thrombocytopenia is the commonest haematological abnormality encountered in the neonatal intensive care unit (NICU). The incidence in neonates varies greatly, depending upon the population studied. The aim of the present study was to study the incidence of thrombocytopenia in the neonates admitted to the NICU.

METHOD

The study was carried out in 258 consecutive eligible neonates from August 2007 to August 2009. Neonates were placed in two risk groups for thrombocytopenia, viz. high risk and low risk, depending upon the presentation, maternal history and any antenatal/perinatal events. Platelet counts were done on the first, third and fifth day of admission and thereafter every 72 hours till counts were normal. Low counts were collaborated with a peripheral blood smear.

RESULTS AND CONCLUSION

The overall incidence of thrombocytopenia in the study group was 70% (182/258). The incidence in the high-risk group was 93.7% cases (134/143) and in the low-risk group was 41.7% (48/115). This difference was statistically significant. Factors associated with thrombocytopenia were sepsis, extreme low birth weight, intra-uterine growth restriction, birth asphyxia and pre-eclampsia in mothers. The most common severe bleeding manifestation was pulmonary haemorrhage. The overall mortality in babies with thrombocytopenia was 33% despite > 90% of these cases having received platelet transfusion. Of these pulmonary haemorrhage was the main cause of death in five cases. It is concluded that thrombocytopenia is very common in the NICU and should be actively looked for so that it can be managed appropriately.

Antibody treatment promotes compensation for human cytomegalovirus-induced pathogenesis and a hypoxia-like condition in placentas with congenital infection

Human cytomegalovirus (HCMV) is the major viral cause of birth defects worldwide. Affected infants can have temporary symptoms that resolve soon after birth, such as growth restriction, and permanent disabilities, including neurological impairment. Passive immunization of pregnant women with primary HCMV infection is a promising treatment to prevent congenital disease. To understand the effects of sustained viral replication on the placenta and passive transfer of protective antibodies, we performed immunohistological analysis of placental specimens from women with untreated congenital infection, HCMV-specific hyperimmune globulin treatment, and uninfected controls. In untreated infection, viral replication proteins were found in trophoblasts and endothelial cells of chorionic villi and uterine arteries. Associated damage included extensive fibrinoid deposits, fibrosis, avascular villi, and edema, which could impair placental functions. Vascular endothelial growth factor and its receptor fms-like tyrosine kinase 1 (Flt1) were up-regulated, and amniotic fluid contained elevated levels of soluble Flt1 (sFlt1), an antiangiogenic protein, relative to placental growth factor. With hyperimmune globulin treatment, placentas appeared uninfected, vascular endothelial growth factor and Flt1 expression was reduced, and sFlt1 levels in amniotic fluid were lower. An increase in the number of chorionic villi and blood vessels over that in controls suggested compensatory development for a hypoxia-like condition. Taken together the results indicate that antibody treatment can suppress HCMV replication and prevent placental dysfunction, thus improving fetal outcome.

Platelet counts and outcome in the pediatric intensive care unit

OBJECTIVES

Thrombocytopenia is commonly observed in critically ill patients. This study was undertaken to evaluate the variation in platelet counts and the risk factors associated with thrombocytopenia and mortality in pediatric intensive care patients. In addition, prognostic value of platelet counts for outcome in pediatric intensive care unit was studied.

STUDY DESIGN

Prospective, observational cohort analysis.

SETTING

8- bedded pediatric intensive care unit of a tertiary care teaching hospital.

PATIENTS

All consecutively admitted patients (n=138) staying in the pediatric intensive care unit (PICU) for at least 48h over a 7 months period were studied.

MEASUREMENTS AND MAIN RESULTS

Thrombocytopenia was defined as platelet counts <150.0/nL. Median 1(st) day Pediatric Risk of Mortality Score (PRISM) was 5 (range 0-30) and median ICU stay was 4 days (range 2-98 days). Twenty five percent patients had at least one episode of thrombocytopenia during the stay. Twenty percent of these patients had thrombocytopenia on admission and rest (80%) developed it during the PICU stay. Seventy one percent (19) of the patients developed thrombocytopenia by fourth day of admission. Patients with PICU acquired thrombocytopenia had statistically significant lower baseline, nadir and 4th day platelet counts and a significantly higher drop in platelet counts (56% vs. 6% P<0.001) as compared to non thrombocytopenic patients. PRISM score, long PICU stay, sepsis, coagulopathy, and creatinine levels were significantly associated with occurrence of thrombocytopenia. Patients with thrombocytopenia had higher probability of bleeding (34% vs. 15%, P=0.01). Higher platelet counts on admission were associated with significantly reduced risk of thrombocytopenia (P=0.00) Baseline, nadir and day-4 platelet counts, presence of thrombocytopenia on admission, sepsis, coagulopathy and a higher mean PRISM score on univariate analysis were significantly associated with mortality. Leucopenia or leucocytosis, thrombocytopenia and coagulopathy were found to significantly affect outcome. Drop in platelet counts was found to have slightly higher discriminative value for mortality prediction than PRISM on the ROC curve. The survivors had higher platelet counts throughout the PICU stay and after an initial fall in platelet counts in the PICU showed a significantly higher rise in the platelet counts in the following days than the non-survivors.

CONCLUSIONS

Thrombocytopenia is common in PICU. Patients requiring cardiopulmonary resuscitation or with circulatory shock, coagulopathy, sepsis and with more severe disease have higher risk of developing thrombocytopenia. Thrombocytopenic patients have a higher risk of bleeding. Drop in platelet counts >27% and thrombocytopenia were independently related to mortality. Serial measurements of platelet counts are better predictors of pediatric intensive care outcome than one-time values. Any drop in platelet counts even without thrombocytopenia needs an urgent and extensive evaluation.

Is thrombocytopenia suggestive of organism-specific response in neonatal sepsis?

BACKGROUND

It is controversial whether thrombocytopenia is suggestive of one (or more) causative agents of neonatal sepsis: a low platelet count has been related in turn to Gram-positive, Gram-negative or fungal sepsis.

METHODS

A retrospective, cohort study on 514 very low-birthweight (VLBW) neonates admitted over a 9 year period to a large tertiary neonatal intensive care unit (NICU) in Italy was carried out. Through database search, data on platelet counts, sepsis, clinical course, and microbiological culture were collected and analyzed. Statistical analysis was performed to look for significant association between thrombocytopenia and sepsis caused by different (Gram-positive, Gram-negative or fungal) organisms.

RESULTS

Sepsis diagnosed on microbiological criteria occurred in 197 of 514 VLBW neonates (38.3%), and thrombocytopenia (at least one finding of platelet count <80,000/mm(3)) was detected in 34 (17.2%) of the 197 septic infants. Thrombocytopenia occurred in 10 of 51 neonates with fungal sepsis (19.6%), and in 24 of 146 with bacterial sepsis (16.4%; P = 0.37). The difference was not significant when clustering for sepsis caused by Gram-positive (nine thrombocytopenic of 51 with Gram-positive sepsis, 17.6%; P = 0.40) and Gram-negative organisms (15/95, 15.7%; P = 0.22), or when considering only coagulase-negative Staphylococcus sepsis (6/37, 16.2%; P = 0.25).

CONCLUSIONS

In contrast with previous reports, thrombocytopenia might not be an organism-specific marker of sepsis. Caution should be maintained in relating a low platelet count to any infectious agent (or group of agents) in preterm VLBW neonates.

Hematologic effects of placental pathology on very low birthweight infants born to mothers with preeclampsia

OBJECTIVE

To investigate the effect of placental pathology on neonatal neutrophils, platelets, hematocrit and nucleated red blood cells in very low birthweight (VLBW) infants born to mothers with preeclampsia.

STUDY DESIGN

Retrospective cohort study of infants with birthweight < 1500 g born to mothers with preeclampsia from july, 2002 to july, 2006 at a single level III neonatal intensive care unit. Placental pathology was reviewed for the presence of placental infarction and vasculopathy. Hematologic parameters from day of life 0, 1 and 2 were obtained. Statistical analysis included repeated-measures analysis of variance and multivariable analysis using logistic regression.

RESULT

The study sample included 203 infants with estimated gestational age of 28+/-3 weeks; 45% had placental infarctions and 26% placental vasculopathy. Infants with neutropenia and thrombocytopenia did not have an increased occurrence of placental infarction or maternal vasculopathy but were more likely to be of small gestational age (SGA) and of lower gestational age compared with infants without neutropenia or thrombocytopenia. After multivariable analysis, gestational age and SGA remained associated with both neutropenia and thrombocytopenia whereas placental infarction and vasculopathy did not remain in the models.

CONCLUSION

In our population of VLBW infants born to mothers with preeclampsia, placental pathology was common. There was no association of placental infarction or vasculopathy with neonatal neutropenia and thrombocytopenia. The data suggest that neonatal hematologic effects of maternal preeclampsia, if related to the placenta, are associated with factors other than placental histology.

The use of blood products in perinatal medicine

Fetal and neonatal medicine is a field with many new procedures and techniques. An increasing number of centres worldwide give intrauterine transfusions, which are considered to be standard-of-care treatment for severe fetal anaemia. The survival of very prematurely born neonates, in particular of a gestational age of <28 weeks, has greatly improved over the last decade but almost all these children need transfusions. Although in many cases such blood transfusions are life saving, randomized, controlled studies investigating appropriate indications, transfusion volume and type of blood product have not been performed. Most of the protocols used are expert based.

How to tackle bleeding and thrombosis in the newborn

Bleeding and its management represent common clinical problems in neonatal intensive care, particularly in pre-term infants. Frank and severe single organ haemorrhage (e.g. pulmonary or gastrointestinal in association with necrotising enterocolitis) is less common, but may require urgent resuscitation and clinical stabilisation. Intracranial bleeding is always potentially of greatest concern because of the neurological consequences, but the pathophysiological mechanism of the most characteristic form, intraventricular haemorrhage, remains incomplete. Minor forms of bleeding are commonly seen in sicker neonates, ranging from blood stained endotracheal secretions to longer than expected oozing from phlebotomy sites, but may be manifestations of disseminated intravascular coagulation. The mainstay of treatment for bleeding in association with abnormalities of coagulation or thrombocytopenia remains blood products, although their role as prophylaxis to prevent bleeding in neonates without clinical signs of haemorrhage is less clear. The overwhelming majority of thromboembolic events in neonates occur in association with arterial or venous catheters, but the clinical features are very variable, including catheter dysfunction and local signs. The optimal treatment strategies including use of anticoagulants remain problematic in the absence of good clinical trials.

Neonatal thrombocytopenia associated with maternal pregnancy induced hypertension

OBJECTIVE

To evaluate the prevalence of thrombocytopenia in neonates born to mothers with pregnancy induced hypertension (PIH) and identify the associated material and neonatal characteristics.

METHODS

In the current, prospective study, platelet counts were assessed serially. Maternal and neonatal characteristic were recorded in pre-designed proforma. Primary outcome measures were thrombocytopenia defined as platelet count of <150,000/mm(3) and severe thrombocytopenia if counts were <30,000/mm(3) or <50,000/mm(3) with bleeding.

RESULTS

Of 97 neonates born to PIH mothers 35 (36.1%) had thrombocytopenia. In 20 (20.6%) thrombocytopenia was severe. Higher percentage of thrombocytopenia was associated with male gender (47.7%), low birth weight (71.4%) and prematurity (67.4%). Severe thrombocytopenia was significantly associated with low birth weight (OR: 4.58; 95% CI: 0.98-21.3; p<0.03) and prematurity (OR: 2.52; 95% CI: 0.87-7.24; p<0.05). Material parity, onset of PIH, and medications did not seem to be associated significantly.

CONCLUSION

Premature and low birth weight neonates born to mothers with pregnancy induced hypertension would require scrutiny for thrombocytopenia during early neonatal period.

Blood and blood component therapy in neonates

Blood component therapy is a very common intervention practiced in newborns; nearly 85% of extremely low birth weight (ELBW) babies get transfusions during their hospital stay. However, there are no set guidelines for transfusion of blood component therapy in newborns. This protocol includes available types of blood components, their methods of preparation, indications and side effects of transfusion, in relation to newborns.

Platelet transfusions

Ever since platelet transfusions were shown to reduce mortality from haemorrhage in patients with acute leukaemia in the 1950s, the use of this therapy has steadily grown to become an essential part of the treatment of cancer, haematological malignancies, marrow failure, and haematopoietic stem cell transplantation. Today, more than 1.5 million platelet products are transfused in the USA each year, 2.9 million products in Europe. However, platelet transfusion can transmit infections and trigger serious immune reactions and they can be rendered ineffective by alloimmunisation. There are several types of platelet components and all can be modified to reduce the chances of many of the complications of platelet transfusion. Transfusion practices, including indications for transfusion, dose of platelets transfused, and methods of treating alloimmunised recipients vary between countries, and even within countries. We review commonly used platelet components, product modifications, transfusion practices, and adverse consequences of platelet transfusions.

Congenital Platelet Disorders

Congenital platelet disorders represent a rare group of diseases classified by either a qualitative or quantitative platelet defect. This article outlines the historical, clinical, laboratory, and genetic features of various inherited platelet disorders with attention given to updated information on disease classification, diagnosis, and genotypes. A separate discussion regarding management addresses the difficulty in treatment strategies, particularly in patients who develop alloimmunization to platelets.

Thrombocytopenia related neonatal outcome in preterms

OBJECTIVE

To investigate the thrombocytopenia and platelet transfusion related outcome in very preterm infants.

METHODS

Cases (n=94) with at least one episode of thrombocytopenia (platelet counts < 150 x 10(9)/L) and controls (n=70) were identified from a database of 1054 neonates with gestational age < or = 32 weeks admitted to a level III NICU. Thrombocytopenia and platelet transfusion related morbidity (IVH, sepsis, NEC, and bleeding) and mortality were analyzed with respect to gestational age (< 28 weeks and 28-32 weeks), severity of thrombocytopenia (mild if platelet count > or = 100 and < 150 x 10(9)/L, moderate if count > or = 50 and < 100 x 10(9)/L, and severe if platelets < 50 x 10(9)/L), age of thrombocytopenia onset (early < 72 hours and late > or =72 hours).

RESULTS

The majority of thrombocytopenia (67.0%) was diagnosed after 72 hours of age, and was mild in 12.8%, moderate in 36.2% and severe in 51.0% of the cases. Neonates with severe and moderate thrombocytopenia were more frequently born at lower gestational age and birth weight. NEC and sepsis especially that caused by Candida infection, were associated with severe thrombocytopenic events. The development of IVH was strongly associated with lower gestational age but not the severity and age of thrombocytopenia onset. Mucocutaneous bleeding complicated 18.4% of cases with severe and late-onset thrombocytopenia (7/38). Platelets were transfused to 85.4% of infants with severe and 64.7% of infants with moderate thrombocytopenia (P< 0.02). The gestational age of the majority of the platelet transfused neonates (49/60, 81.7%) was < 28 weeks. Mean gestational age and birth weight, and rates of severe thrombocytopenia, IVH, sepsis and mortality were comparable in transfused vs not-transfused infants with gestational age 28-32 weeks. Platelet transfused neonates with gestational age < 28 weeks had lower birth weights, were more often severely thrombocytopenic, and died more frequently than infants of a similar gestational age who were not transfused.

CONCLUSION

Platelet transfusions did not lower mortality in very premature born infants with moderate and severe thrombocytopenia during the NICU admission.

Recent advances in the prevention and treatment of congenital cytomegalovirus infections

Continued but slow progress has led to recent advances in our understanding that congenital cytomegalovirus (CMV) infection has occurred. We understand that the most severe congenital disease occurs following a primary maternal infection during pregnancy. We now have the ability to accurately diagnosis a primary maternal infection using serologic studies of single serum sample. For pregnant women with young children, we know that child-to-mother CMV transmission can probably be prevented by hygienic intervention, and that for pregnant women who have acquired a primary CMV infection, mother-to-fetal transmission is probably preventable using CMV hyperimmune globulin. Although additional studies are needed, treatment of congenitally infected fetuses or newborns should be possible using either CMV hyperimmune globulin or antiviral agents such as ganciclovir or its derivates. Finally, recent evidence indicates that CMV replicates in the placenta, impairs development, and causes inflammation and dysfunction. This plus the reversibility of many manifestations of congenital infection in the fetus and newborn indicate that congenital CMV disease is in part a syndrome of placental insufficiency.

Acute immune thrombocytopenic purpura in infants: associated factors, clinical features, treatment and long-term outcome

The natural course of acute immune thrombocytopenic purpura (ITP) in infants is poorly described in the literature. A retrospective study of 17 consecutive patients <1 yr of age admitted and treated for acute ITP between 1996 and 2005 was conducted. We investigated their demographics, vaccination history, clinical features, laboratory examinations, response to treatment and long-term outcome. There were 11 male and six female infants. Their ages ranged from 24 d to 12 months with a median of 3 months. All infants presented with petechiae and/or ecchymoses. Fourteen cases had platelet counts below 20 x 10(9)/L at the time of admission. They all had good response to a single course of treatment (14/17) or multiple courses of treatment (3/17). None had progressed into chronic ITP. Seven infants had a causal relationship with immunization, five associated with hepatitis B, one diphtheria-pertussis-tetanus, one diphtheria-tetanus-acellular pertussis-inactivated poliovirus vaccine-conjugated Haemophilus influenza vaccines. These seven infants responded to treatment within 3-9 d after therapy with intravenous immunoglobulin, high-dose methylprednisolone or oral steroids. Re-boosters with vaccines revealed no recurrence of the disease in all of these seven patients. The study suggests that further immunization is not contraindicated in infants experiencing acute ITP associated with vaccines.

Laboratory parameters predictive of developing necrotizing enterocolitis in infants born before 33 weeks of gestation

PURPOSE

The aim of this study was to identify laboratory findings predictive of necrotizing enterocolitis (NEC).

METHODS

Prospective follow-up of 140 infants of less than 33 weeks of gestation. Twenty-six infants developed NEC (grades I to III, criteria of Bell et al [Ann Surg 1978;187:1-7]) (NEC group). For each, 2 birth-weight, gestational age- and postnatal age-matched controls were selected (control group). Blood counts, glucose and electrolyte levels, C-reactive protein, and acid-base balance 3 days, 2 days, and 1 day before and at the onset of NEC and at corresponding ages from the controls were recorded.

RESULTS

Metabolic acidosis occurred, the platelet levels decreased, and the blood glucose increased on successive days in the infants with grade NEC II-III. At the onset of NEC, the infants had significantly lower platelet and higher blood glucose levels compared with controls. More than half of infants with intestinal perforation had leukocyte levels above 30 x 10(9)/L and pH less than 7.25, and their mean blood glucose levels increased to more than 1.5 mmol/L in 24 hours. The remaining parameters were not useful.

CONCLUSION

A persistent metabolic acidosis, decreasing platelet, and increasing blood glucose level on several successive days might predict a developing NEC, and leukocyte values above 30 x 10(9)/L, pH less than 7.25, and a blood glucose rise by 1.5 mmol/L or more within 24 hours predict NEC with intestinal perforation. Such findings should alert the physician to look for signs of NEC in a preterm infant.

A prospective pilot study of prophylactic treatment of preterm neonates with recombinant activated factor VII during the first 72 hours of life

OBJECTIVE

Intraventricular hemorrhage (IVH) in the preterm infant is a devastating complication, causing marked mortality and morbidity. A general hemostatic agent such as recombinant activated factor VII (rFVIIa) might have the potential to reduce the extent of severe IVH.

DESIGN

Prospective, single-arm pilot study.

SETTING

Level III neonatal intensive care unit.

PATIENTS

Ten preterm infants between 23 and 28 wks of gestation.

INTERVENTION

Administration of a 100-microg/kg rFVIIa bolus injection within the first 2 hrs of life, followed by 100 microg/kg rFVIIa every 4 hrs, for the first 72 hrs of life.

MEASUREMENTS AND MAIN RESULTS

Cranial ultrasonography and flow studies of the major arteries and the venae cava, aorta, vena portae, and venae renales, was performed at study enrollment and at 12 hrs, 24 hrs, 48 hrs, and 72 hrs. Blood cell counts and coagulation studies were performed. End points of the study were occurrences of adverse events, with an emphasis on thrombotic events or disseminated intravascular coagulation (DIC). Ten preterm infants with a gestational age of 23 wks 1 day to 28 wks 3 days were included. None had venous thrombosis or cerebral infarction during or after the treatment. Neither platelet consumption nor DIC was observed. Two infants with an umbilical artery catheter had a thrombus at the catheter tip (one during infusion of the study drug), which was successfully treated with heparin. One had grade III IVH and died on day 6 of life; in another, grade II IVH progressed to grade III after termination of the drug.

CONCLUSION

One hundred microg/kg rFVIIa does not accumulate if administered prophylactically to preterm infants of <28 wks of gestation every 4 hrs in the first 72 hrs of life. In this population, rFVIIa does not cause DIC. Thrombus formation was observed in two infants with umbilical artery catheters but in none of the infants with venous catheters. Embolic events were not observed. In this pilot study, which did not provide the sample size to assess any effect of rFVIIa on the incidence of IVH, 20% of the neonates went on to have grade III or IV IVH, which is similar to the rate in studies in which rFVIIa was not given.