tPA Mobilizes Immune Cells That Exacerbate Hemorrhagic Transformation in Stroke

RATIONALE

Hemorrhagic complications represent a major limitation of intravenous thrombolysis using tPA (tissue-type plasminogen activator) in patients with ischemic stroke. The expression of tPA receptors on immune cells raises the question of what effects tPA exerts on these cells and whether these effects contribute to thrombolysis-related hemorrhagic transformation.

OBJECTIVE

We aim to determine the impact of tPA on immune cells and investigate the association between observed immune alteration with hemorrhagic transformation in ischemic stroke patients and in a rat model of embolic stroke.

METHODS AND RESULTS

Paired blood samples were collected before and 1 hour after tPA infusion from 71 patients with ischemic stroke. Control blood samples were collected from 27 ischemic stroke patients without tPA treatment. A rat embolic middle cerebral artery occlusion model was adopted to investigate the underlying mechanisms of hemorrhagic transformation. We report that tPA induces a swift surge of circulating neutrophils and T cells with profoundly altered molecular features in ischemic stroke patients and a rat model of focal embolic stroke. tPA exacerbates endothelial injury, increases adhesion and migration of neutrophils and T cells, which are associated with brain hemorrhage in rats subjected to embolic stroke. Genetic ablation of annexin A2 in neutrophils and T cells diminishes the effect of tPA on these cells. Decoupling the interaction between mobilized neutrophils/T cells and the neurovascular unit, achieved via a S1PR (sphingosine-1-phosphate receptor) 1 modulator RP101075 and a CCL2 (C-C motif chemokine ligand 2) synthesis inhibitor bindarit, which block lymphocyte egress and myeloid cell recruitment, respectively, attenuates hemorrhagic transformation and improves neurological function after tPA thrombolysis.

CONCLUSIONS

Our findings suggest that immune invasion of the neurovascular unit represents a previously unrecognized mechanism underlying tPA-mediated brain hemorrhage, which can be overcome by precise immune modulation during thrombolytic therapy.

Maternal anti-platelet β3 integrins impair angiogenesis and cause intracranial hemorrhage

Fetal and neonatal alloimmune thrombocytopenia (FNAIT) is a life-threatening disease in which intracranial hemorrhage (ICH) is the major risk. Although thrombocytopenia, which is caused by maternal antibodies against β3 integrin and occasionally by maternal antibodies against other platelet antigens, such as glycoprotein GPIbα, has long been assumed to be the cause of bleeding, the mechanism of ICH has not been adequately explored. Utilizing murine models of FNAIT and a high-frequency ultrasound imaging system, we found that ICH only occurred in fetuses and neonates with anti-β3 integrin-mediated, but not anti-GPIbα-mediated, FNAIT, despite similar thrombocytopenia in both groups. Only anti-β3 integrin-mediated FNAIT reduced brain and retina vessel density, impaired angiogenic signaling, and increased endothelial cell apoptosis, all of which were abrogated by maternal administration of intravenous immunoglobulin (IVIG). ICH and impairment of retinal angiogenesis were further reproduced in neonates by injection of anti-β3 integrin, but not anti-GPIbα antisera. Utilizing cultured human endothelial cells, we found that cell proliferation, network formation, and AKT phosphorylation were inhibited only by murine anti-β3 integrin antisera and human anti-HPA-1a IgG purified from mothers with FNAIT children. Our data suggest that fetal hemostasis is distinct and that impairment of angiogenesis rather than thrombocytopenia likely causes FNAIT-associated ICH. Additionally, our results indicate that maternal IVIG therapy can effectively prevent this devastating disorder.

Immunohistohemical expression of the chemokine fractalkine and its receptor in the human brain cortex after severe traumatic brain injury and brain hemorrhage

AIM

Recent experimental studies have suggested that chemokines, a subclass of chemoattractant cytokines which play an important role in regulating leukocyte migration and intercellular communication, participate in brain responses of traumatic injury. Fractalkine (CX3CL1) is a peculiar chemokine, the only one with a CX3C motif, existing both as a soluble and a membrane-anchored molecule. In the brain, Fractalkine has been suggested to have a role in neuroprotection under experimental conditions of brain injury.

METHODS

Eighteen human brain samples were obtained during surgery of decompressive craniotomy for severe traumatic brain injury (TBI) or after spontaneous intracranial haemorrhage (ICH). Five normal brain samples were obtained during surgery for unruptured intracranial aneurysms (standard gyrectomy). Immunohistochemistry of formalin fixed and paraffin embedded tissues was performed in order to verify the expression of fractalkine and its receptor (CX3CR1). The values of chemokine and receptor expression were correlated with the clinical parameters of the patients.

RESULTS

The chemokine fractalkine was significantly upregulated in the neural compartment after brain injury, compared to normal brain samples. Intensity scores were significantly higher when the interval between injury and surgery was >5 h, (P=0.015). In the glial compartment, Fractalkine expression was significantly associated with less severe clinical conditions and lower intracranial pressure at surgery (P=0.014). Expression of the receptor CX3CR1 was detected, at low intensity, on both glial and neurons. Higher expression in neurons was associated with better clinical conditions (Glasgow score) of patients at admission (P=0.037).

CONCLUSION

The results of this study highlights for the first time that fractalkine and its receptor CX3CR1 are expressed in the human brain after TBI and ICH and may be involved in the limitation of tissue damage.

Replication of genetic associations in the inflammation, complement, and coagulation pathways with intraventricular hemorrhage in LBW preterm neonates

Intraventricular hemorrhage (IVH) is a significant morbidity seen in very LBW infants. Genes related to the inflammation, infection, complement, or coagulation pathways have been implicated as risk factors for IVH. We examined 10 candidate genes for associations with IVH in 271 preterm infants (64 with IVH grades I-IV and 207 without IVH) weighing <1500 g. The heterozygous genotype OR = 8.1, CI = 2.5-26.0, p = 4 × 10(-4)) and the A allele (OR = 7.3, CI = 2.4-22.5, p = 1 × 10(-4)) of the coagulation factor V (FV) Leiden mutation (rs6025) were associated with an increased risk of developing IVH grade I or II but not grade III or IV after correction for multiple testing with Bonferroni. Lack of association in the severe grades of IVH may be a result of lack of power to detect an effect given the small sample size (n = 8). However, this result is consistent with previous research that demonstrates that the heterozygous genotype of the FV mutation is associated with increased risk for the development of IVH but a decreased risk for the progression or extension to more severe grades of IVH.

Immunologic and structural analysis of eight novel domain-deletion beta3 integrin peptides designed for detection of HPA-1 antibodies

BACKGROUND

The single-nucleotide polymorphism (SNP) rs5918 in the ITGB3 gene defines the human platelet antigen-1 (HPA-1) system encoding a Leu (HPA-1a) or Pro (HPA-1b) at position 33. HPA-1 antibodies are clinically the most relevant in the Caucasoid population, but detection currently requires alpha(IIb)beta3 integrin from the platelets of HPA-genotyped donors.

OBJECTIVES

We set out to define the beta3 integrin domains required for HPA-1a antibody binding and produce recombinant soluble beta3 peptides for HPA-1 antibody detection.

METHODS

We designed two sets (1a and 1b) of four soluble beta3 domain-deletion peptides (deltaSDL, deltabetaA, PSIHybrid, PSI), informed by crystallography studies and computer modeling. The footprints of three human HPA-1a-specific phage antibodies were defined by analyzing binding patterns to the beta3 peptides and canine platelets, and models of antibody-antigen interfaces were derived. Specificity and sensitivity for HPA-1a detection were assessed using sera from 140 cases of fetomaternal alloimmune thrombocytopenia (FMAIT).

RESULTS

Fusion of recombinant proteins to calmodulin resulted in high-level expression in Drosophila S2 cells of all eight beta3 peptides. Testing of FMAIT samples indicated that deltabetaA-Leu33 is the superior peptide for HPA-1a antibody detection, with 96% sensitivity and 95% specificity. The existence of type I and II categories of HPA-1a antibodies was confirmed by the study of HPA-1a phage antibody footprints and the reactivity pattern of clinical samples with the four beta3-Leu33 peptides, but there was no correlation between antibody category and clinical severity of FMAIT.

CONCLUSIONS

Soluble recombinant beta3 peptides can be used for detection of clinical HPA-1a antibodies.

[Immune mechanisms in the development of hemorrhagic stroke]

The role played by immune mechanisms in intracerebral hemorrhage (ICH) was evaluated based on the studies of thymus structure and cell composition in rats showing different degree of tolerance to emotional stress. A new experimental ICH model is proposed. It is concluded that both stereotype and autoimmune mechanisms are involved in the development of ICH.

Immunotherapy against APP β-Secretase Cleavage Site Improves Cognitive Function and Reduces Neuroinflammation in Tg2576 Mice without a Significant Effect on Brain Aβ Levels

BACKGROUND/OBJECTIVES

Active and passive immunization methodologies against amyloid-beta (Abeta) are employed to clear and reduce cerebral Abetatowards treatment of Alzheimer's disease (AD) patients. The therapeutic potential of these antibodies in AD patients is limited because of adverse inflammatory reactions and cerebral hemorrhage, which are associated with the treatment. We propose a novel approach to inhibit Abeta production via antibodies against the beta-secretase cleavage site of the amyloid precursor protein (APP). Such an approach limits APP processing by beta-secretase, mainly through the endocytic pathway, and overcomes some of the limitations of BACE inhibition. Anti-APP beta-site antibodies, tested in a cellular model expressing wild-type APP, were found to bind full-length APP, internalize into the cells and interfere with BACE activity, inhibiting both intra- and extracellular Abeta peptide formation.

METHODS

We investigated the effect of anti-beta-site antibodies in an AD animal model regarding antibody efficacy, as well as possible adverse effects in the brain and periphery that may result from antibody treatment.

RESULTS/CONCLUSIONS

Here, we show that long-term systemic administration of anti-APP beta-site antibodies to Tg2576 transgenic mice improved mouse cognitive functions associated with a reduction in both brain inflammation and the incidence of microhemorrhage. Furthermore, antibody treatment did not induce any peripheral autoimmunity responses. In spite of the beneficial effects observed in antibody-treated mice, brain Abeta levels were not altered as a result of antibody treatment.

A screening and intervention program aimed to reduce mortality and serious morbidity associated with severe neonatal alloimmune thrombocytopenia

The study's objective was to identify HPA 1a-negative women and to offer them an intervention program aimed to reduce morbidity and mortality of neonatal alloimmune thrombocytopenia (NAIT). HPA 1 typing was performed in 100 448 pregnant women. The HPA 1a-negative women were screened for anti-HPA 1a. In immunized women, delivery was performed by Cesarean section 2 to 4 weeks prior to term, with platelets from HPA 1a-negative donors reserved for immediate transfusion if petechiae were present and/or if platelet count was less than 35 x 10(9)/L. Of the women screened, 2.1% were HPA 1a negative, and anti-HPA 1a was detected in 10.6% of these. One hundred seventy pregnancies were managed according to the intervention program, resulting in 161 HPA 1a-positive children. Of these, 55 had severe thrombocytopenia (< 50 x 10(9)/L), including 2 with intracranial hemorrhage (ICH). One woman with a twin pregnancy missed the follow-up and had one stillborn and one severely thrombocytopenic live child. In 15 previous prospective studies (136 814 women) there were 51 cases of severe NAIT (3 intrauterine deaths and 7 with ICH). Acknowledging the limitation of comparing with historic controls, implementation of our screening and intervention program seemed to reduce the number of cases of severe NAIT-related complications from 10 of 51 to 3 of 57.

Intrakranielle Blutung bei erworbener Hemmkörperhämophilie

Acquired hemophilia is a rare complication in autoimmune disorders and malignancies. It can result in bleedings into skin and muscle, whereas intracranial hemorrhage in adults has so far not been described. We report a patient with acute intracerebral hemorrhage due to acquired hemophilia with factor VIII inhibition. The patient was treated with recombinant factor VIIa and open hematoma evacuation followed by administration of cortisone and cyclophosphamide. After good initial recovery, intracerebral rebleeding occurred and the patient died from brainstem compression.

Pharmacological brain cooling with indomethacin in acute hemorrhagic stroke: antiinflammatory cytokines and antioxidative effects

We evaluated the effects of a novel pharmacological brain cooling (PBC) method with indomethacin (IND), a nonselective cyclooxygenase inhibitor, without the use of cooling blankets in patients with hemorrhagic stroke. Forty-six patients with hemorrhagic stroke (subarachnoid hemorrhage; n = 35, intracerebral hemorrhage; n = 11) were enrolled in this study. Brain temperature was measured directly with a temperature sensor. Patients were cooled by administering transrectal IND (100 mg) and a modified nasopharyngeal cooling method (positive selective brain cooling) initially. Brain temperature was controlled with IND 6 mg/kg/day for 14 days. Cerebrospinal fluid concentrations of interleukin-1beta (CSF IL-1beta) and serum bilirubin levels were measured at 1, 2, 4, and 7 days. The incidence of complicating symptomatic vasospasm after subarachnoid hemorrhage was lower than in non-PBC patients. CSF IL-1beta and serum bilirubin levels were suppressed in treated patients. IND has several beneficial effects on damaged brain tissues (anticytokine, free radical scavenger, antiprostaglandin effects, etc.) and prevents initial and secondary brain damage. PBC treatment for hemorrhagic stroke in patients appears to yield favorable results by acting as an antiinflammatory cytokine and reducing oxidative stress.

Novel approaches for immunotherapeutic intervention in Alzheimer's disease

Immunotherapy can attenuate amyloid neuropathology and improve cognitive function in transgenic models of Alzheimer's disease. However, the first clinical trial was halted when 6% of the Alzheimer's patients developed aseptic meningoencephalitis. Postmortem analysis of two cases with meningoencephalitis showed robust glial activation, T-cell infiltration and sporadic clearance of Abeta. Interestingly, transgenic mouse models of Alzheimer's disease failed as predictors of these adverse inflammatory events. However there are now several studies with amyloid precursor protein transgenic mice that have reported an increased risk of microhemorrhages at sites of cerebrovascular amyloid deposits and because approximately 80% of Alzheimer's patient's have cerebrovascular pathology, there is concern regarding clinical trials using passive administration of humanized anti-Abeta antibodies. Although many studies have now been published on immunotherapy in mouse models, the mechanism(s) of antibody-mediated clearance of beta-amyloid from the brain, and the cause of the antibody-induced microhemorrhages remain unclear. In this review, we will discuss the most recent results from the first clinical trial, offer speculation on possible causes for the failure of the trial, review data on antibody-mediated clearance mechanisms, explore the role of complement and inflammation in the clearance of beta-amyloid, and suggest novel strategies for avoiding problems in future clinical trials. The central hypothesis being proposed in this review is that anti-Abeta antibodies delivered directly to the CNS at the sites of amyloid deposits will be far more effective at clearing Abeta and safer than active or passive immunization strategies where the majority of the antibodies are in the periphery.

Pregnancy in mother with Glanzmann's thrombasthenia and isoantibody against GPIIb–IIIa: Is there a foetal risk?

Glanzmann's thrombasthenia (GT) is a rare autosomal recessive platelet disorder caused by qualitative or quantitative abnormalities of a platelet glycoprotein complex (GPIIb-IIIa) leading to excessive bleeding. Platelet transfusions are the first-line therapy for severe or persistent bleeding and surgery. Isoantibody against GPIIb-IIIa complexes present on normal platelets can be observed in Glanzmann's thrombasthenia type I patients after platelet transfusion possibly leading to platelet transfusion refractoriness. Pregnancy in Glanzmann's thrombasthenia type I women is rare, and severe bleeding can be observed in the peripartum or late postpartum period. Moreover, pregnancy can contribute to the maternal isoimmunization by the passage of the foetal cells into the maternal circulation. The transplacental passage of the maternal isoantibodies can induce moderate to severe foetal thrombocytopenia. We discuss here the case of in utero death at 31 weeks of gestation due to intracranial haemorrhage in an immunized mother and review the literature. Presence of isoantibody prior to gestation or detected during the index pregnancy must be taken into account in evaluating risk for the mother and the foetus.

Effect of maternal anti-HPA-1a antibodies and polyclonal IVIG on the activation status of vascular endothelial cells

Maternal anti-HPA-1a antibodies can cause severe fetal and neonatal alloimmune thrombocytopenia (FNAIT), complicated by intracranial haemorrhage (ICH). Antenatal treatment with maternal intravenous immunoglobulin (IVIG) seems to protect against ICH even when thrombocytopenia persists. The aim of this study was to investigate if anti-HPA-1a antibodies and IVIG potentially affect vascular endothelial cells (ECs) in order to identify susceptibility for ICH. Human umbilical cord endothelial cells (HUVEC) were incubated with anti-HPA-1a antibodies with or without polyclonal IVIG and evaluated for EC activation. Maternal sera with anti-HPA-1a antibodies affected neither the EC expression of intracellular adhesion molecule-1 (ICAM-1), vascular adhesion molecule-1 (VCAM-1) and tissue factor (TF) nor the release of van Willebrand factor (vWF) or interleukin (IL)-8 nor the integrity of ECs. Maternal sera obtained after IVIG treatment and polyclonal IVIG decrease constitutive and cytokine-induced ICAM-1 and VCAM-1 expression on ECs. The results show that maternal anti-HPA-1a antibodies cause no activation or damage of ECs in this model. The clinical relevance of the de-activating properties of IVIG on EC activation with respect to ICH deserves further investigation.

Study on relationship between anticardiolipin antibody and cerebrovascular diseases

Serum anticardiolipin antibody (ACA) was measured in 91 patients with cerebral infarction (CI), 42 patients with cerebral hemorrhage (CH) and 30 healthy controls. The results showed that the ACA in CI and CH patients was significantly higher than in controls and IgG-ACA was the most important isotype. Stroke in ACA positive group tended to be recurrent and of multi-focuses. Positive rate of IgG-ACA reached its peak within the first week after stroke onset. The results suggested that ACA was an independent risk factor in CI and CH and might be valuable in stroke prediction.

[The role of autoimmune process in the pathogenesis of hemorrhagic stroke]

Using immunologic study along with clinical and neurological ones, 104 patients in acute stage of hemorrhage stroke (18% of them with subarachnoidal; 27%--with parenchymatous and 55%--with combined hemorrhage) have been examined. A level of antibodies to DNA (anti-DNA) was determined in cerebrospinal fluid (CSF) and blood serum on 1, 10 and 20 days. Control group consisted of 20 persons. Anti-DNA was significantly elevated on day 1 in CSF and blood serum, with the most pronounced increasing in CSF (p < 0.001). The severer was hemorrhage stroke, the higher was anti-DNA level. Furthermore, the poorer was prognosis for recovery and life, the higher elevation was detected for anti-DNA.

[Circulating immune complexes in ischemic and hemorrhagic strokes]

The study aimed at determination of circulating immune complexes (CIC) levels in a serum of patients with ischemic and hemorrhagic strokes, isolation of the complexes and their antigen composition identification. Spectrophotometric assay, polyethylene glycol precipitation and SDS PAG electrophoresis were used. Comparing to controls, significantly elevated levels of both small and big CIC were detected in the serum of the patients with ischemic stroke, while in the patients with hemorrhage stroke only the level of small CIC was elevated. The antigen CIC composition was specific for each stroke form and for control group either. Being compared to literature data, the results obtained revealed a specificity of the antigen CIC composition in ischemic and hemorrhagic strokes.

Clinico-pathological study of meningiomas with haemorrhagic onset

BACKGROUND

Haemorrhage from meningiomas is rare and the underlying pathophysiological mechanisms remain to be determined. We sought to identify these mechanisms by studying clinical and histological records of 6 meningioma patients treated at our institution.

PATIENTS AND METHODS

We retrospectively studied 6 patients with meningiomas whose acute onset was due to haemorrhage. We evaluated clinical features and imaging studies. The vascularity and proliferative nature of these tumours were examined immunohistochemically and tissue factor (TF) immunoreactivity was assessed. For comparison we evaluated 25 non-haemorrhagic meningiomas.

FINDINGS

At onset, the haemorrhages mimicked stroke in all 6 patients. On imaging studies, 3 of the haemorrhages were intra- and extratumoural, the other 3 were extratumoural only. Hyperintensity on T2-weighted MRI was a characteristic of these meningiomas. Histologically, they were of 3 subtypes, meningothelial (n=3), transitional (n=2), and anaplastic (n=1). The MIB-1 labelling index of the 5 WHO Grade I meningiomas was 5.8+/-2.2. The mean number of CD31-positive blood vessels did not differ in haemorrhagic and non-haemorrhagic meningiomas. The TF-positivity rate of haemorrhagic meningiomas was higher than of non-haemorrhagic meningiomas.

INTERPRETATION

The proliferative nature of the meningiomas and TF expression in tumour cells may have contributed to the eventual haemorrhage of the meningiomas in our series.

European collaborative study of the antenatal management of feto-maternal alloimmune thrombocytopenia

The aims of this study were to determine whether the severity of fetomaternal alloimmune thrombocytopenia (FMAIT) in the current pregnancy could be predicted from the history of FMAIT in previous pregnancies, and to assess the effects of different types of antenatal intervention. Fifty-six fetuses were studied that all had a sibling affected by FMAIT due to human platelet antigen 1a (HPA-1a) alloimmunization. Cases with a sibling history of antenatal intracranial haemorrhage (ICH) or severe thrombocytopenia (platelet counts of < 20 x 109/l) had significantly lower pretreatment platelet counts than cases whose siblings had less severe thrombocytopenia or postnatal ICH. Maternal therapy resulted in a platelet count exceeding 50 x 109/l in 67% of cases. None of the fetuses managed by serial platelet intrauterine transfusions (IUT) suffered ICH following treatment. However, several serious complications arose with fetal blood sampling (FBS). Overall, intervention improved outcome, as three study cases suffered from antenatal ICH and three others died whereas 15 study cases had a sibling with an ICH, eight of whom died. The results of this study suggest that the start of therapy can be stratified on the basis of the sibling history of FMAIT, and support the use of maternal therapy as first-line treatment.

Intracranial hemorrhage in systemic lupus erythematosus associated with an autoantibody against actor XIII

Intracranial hemorrhage in a young woman with systemic lupus erythematosus necessitated two surgical evacuations. In the absence of a family history of bleeding, clot solubility in urea suggested a factor XIII (FXIII) inhibitor. The patient's IgG bound well to the virgin and the thrombin-modified zymogen ensemble (A(2)B(2) and A(2)'B(2)) and to the free rA(2) but reacted poorly with the thrombin-modified rA(2)'. Since the IgG did not block the thrombin-catalyzed proteolysis of A subunits nor the dissociation of the A(2)'B(2), its action might be to interfere with the release of activation peptides from the thrombin-cleaved zymogen, hindering the conformational change necessary for generating FXIIIa. Treatment with cryoprecipitate and cyclophosphamide arrested the hemorrhage and almost neutralized the antibody so that the patient's clot became insoluble in urea and showed a close to normally crosslinked gamma-gamma and alpha(n) fibrin chain profile. Nevertheless, she still has detectable anti-FXIII antibody and may be at risk for hemorrhage.

[Acute phase response after stroke: differences between ischemic stroke and intracerebral hemorrhage]

BACKGROUND

To evaluate differences in the temporal profile of acute phase response (APR) between ischemic stroke (IS) and intracerebral hemorrhage (ICH).

PATIENTS AND METHOD

We studied APR parameters (< 24 h and 3-5 day) in 88 consecutive patients (43 ICH and 45 IS). The increase/decrease of the parameters between both dates was analyzed.

RESULTS

Leukocyte increase (LI) and fibrinogen increase (FI) is significantly higher in ICH than in IS (p = 0.047 and p = 0.035).

CONCLUSIONS

APR temporal profile is different for ICH and IS.

[Evaluation of gradual conversion to a less invasive therapeutic strategy for pregnant women with alloimmune thrombocytopenia in the fetus for prevention of intracranial hemorrhage]

OBJECTIVE

To evaluate a less invasive management strategy for pregnant women with neonatal alloimmune thrombocytopenia without a history of intracranial haemorrhage.

DESIGN

Retrospective and descriptive.

METHOD

In Leiden University Medical Centre, the Netherlands, in the period 1994-August 1999, 31 women with 32 pregnancies were treated. Six women had a history of a sibling with thrombocytopenia and intracranial haemorrhage and 26 a history of a sibling with (severe) thrombocytopenia without haemorrhage. Treatment options consisted of weekly administered intravenous immunoglobulin (ivIG) to the mother without diagnostic cordocentesis, cordocentesis with foetal blood sampling and intrauterine platelet transfusions to the fetus. In the group without history of intracranial haemorrhage fetal blood sampling and platelet transfusion were gradually abandoned as much as possible.

RESULTS

In the children of the treated pregnant women there were no instances of intracranial haemorrhage. In addition, the platelet count in cord blood was higher, compared with patients treated before 1994 and with literature data.

CONCLUSION

A less invasive management strategy in case of a history without intracranial haemorrhage seems justified based on results in our population. Administration of ivIG without diagnostic cordocentesis, however, results in a lost opportunity to verify the indication and the effectiveness of treatment.