No abstract available.
Thrombocytopenia, Neonatal Alloimmune*

No abstract available.
Thrombocytopenia, Neonatal Alloimmune*

No abstract available.
Thrombocytopenia, Neonatal Alloimmune*

No abstract available.
Thrombocytopenia, Neonatal Alloimmune*

BACKGROUND: Platelet antigen and antibody tests have been used in platelet immunological disorders, such as neonatal alloimmune thrombocytopenia (NAIT) and post-transfusion purpura (PTP). Mixed passive hemagglutination (MPHA) method has several advantages, including frozen preservation of platelets, ability to differentiate between anti-HLA and platelet-specific antibodies, and quick and easy interpretation without expensive equipment. In this study, we intended to develop the MPHA method using indicator cells of anti-Rh(D) sensitized group O, Rh+ RBCs. METHODS: We made indicator cells sensitized with anti-Rh(D) with various strengths (1:32 to 1:256) and determined the optimal strength. We determined the sensitivity of the MPHA and compared the results using flow cytometry. We observed the changes of the reaction according to the storage time of indicator cells. RESULTS: The optimal sensitization strengths of the indicator cells were 1:192 and 1:256. MPHA showed strong positive results with 1:8,192 diluted positive control, while the detection limit of flow cytometry was 1:128. Until the second week (mean 16 days), the indicator cells showed good results comparable to those of fresh ones. CONCLUSION: We developed the MPHA method using indicator cells of anti-Rh(D) sensitized group O, Rh+ RBCs. We produced the indicator cells in our own laboratory and obtained platelet panels with rare antigen typing using frozen-stored platelets. This technology will be used effectively for detection of platelet antigens and identification of platelet antibodies and also for platelet crossmatching.
Antibodies ; Blood Platelets* ; Flow Cytometry ; Hemagglutination* ; Limit of Detection ; Purpura ; Thrombocytopenia, Neonatal Alloimmune

Immune thrombocytopenia (ITP) is a common acquired hemorrhagic disease. Conventional view considered its pathogenesis as the destruction of platelets induced by platelet associated antibodies, the target of treatment are inhibiting the production of antibodies and blocking the destruction of platelets in reticuloendothelial system, but they are ineffective in part of ITP patients, who transform to chronic/refractory ITP (C/RITP). As to children's C/RITP, the effect of first-line therapy is low, while the second-line therapy isn't effective definitely and has obvious side effects. The safe and effective second-line drugs to prevent disease progressing are urgently required. Recently, a pathogenesis that decrease the platelet production has been confirmed, thrombopoietic drugs, including thrombopoietin (TPO) and its receptor agonist (TRA), are under research and clinical application gradually. Recombinate human TPO (rhTPO) has accomplished Phase III clinical trails in adult C/RITP and tumor children. The Phase III clinical trails of romiplostim and eltrombopag, as the representative of TRA, in adult C/RITP have been performed. There are also two clinical trails of TRA for children's C/RITP, the efficacy and safety have been approved, with the convenience for using. In pediatric population, they have a good clinical application. In this article the research and development of thrombopoietic drugs and their perspective in pediatric clinical use are reviewed.
Child ; Clinical Trials, Phase III as Topic ; Humans ; Thrombocytopenia ; drug therapy ; etiology ; Thrombocytopenia, Neonatal Alloimmune ; drug therapy ; Thrombopoietin ; therapeutic use

Neonatal thrombocytopenia, defined as platelet counts of less than 150,000/µL, is a frequent hematologic abnormality in neonatal period. Differential diagnosis of neonatal thrombocytopenia may be challenging to pediatric hematologists and neonatologists because neonatal thrombocytopenia is associated with diverse maternal or neonatal clinical conditions. An accurate diagnosis for neonatal thrombocytopenia will lead to appropriate evaluation and management. Platelet transfusion is the primary management of neonatal thrombocytopenia. Most thrombocytopenic newborns received platelet concentrates to prevent major hemorrhage or treat ongoing bleeding according to institutional policy. However, scientific evidences for benefit and consistent guideline for platelet transfusion in neonates are lacking, further investigation to establish the standard recommendation for platelet transfusion is needed. This article reviewed the diagnostic approach and current guideline for platelet transfusion management for neonatal thrombocytopenia.
Blood Platelets ; Diagnosis ; Diagnosis, Differential ; Hemorrhage ; Humans ; Infant ; Infant, Newborn ; Organizational Policy ; Platelet Count ; Platelet Transfusion ; Thrombocytopenia ; Thrombocytopenia, Neonatal Alloimmune

This study was aimed to investigate the detection and diagnosis of the neonatal alloimmune thrombocytopenia purpura (NAITP) caused by anti-HPA-5b antibody. The platelet count and clinical manifestation in the newborn were examined. The HPA-1-21bw genotypes of the newborn and her parents were detected by multiple-PCR and DNA sequencing. The HPA-specific antibody in the sera of newborn and her mother were detected and identified by flow cytometry (FCM) and monoclonal antibody-specific immobilization of platelet antigens (MAIPA). The results indicated that the clinical manifestations of the newborn were lighter. The HPA genotyping showed that the genotype of the newborn was HPA-5ab, while that of her mother and father were HPA-5aa and HPA-5ab, respectively. The antibody against the platelet of newborn's father existed in the newborn's mother sera. The HPA antibody of the mother was identified as anti-HPA-5b. It is concluded that the newborn with neonatal alloimmune thrombocytopenia purpura was caused by the antibody against HPA-5b.
Antigens, Human Platelet ; genetics ; China ; Female ; Genotype ; Humans ; Infant, Newborn ; Purpura, Thrombocytopenic, Idiopathic ; diagnosis ; genetics ; Thrombocytopenia, Neonatal Alloimmune ; diagnosis ; genetics

Neonatal alloimmune thrombocytopenia(NAIT) is a very rare disease caused by maternal alloantibodies' response to neonatal platelet antigens. Because the most common cause of NAIT is incompatibility for platelet-specific antigens, NAIT cases due to anti-HLA antibodies are very exceptional. The patient was a second born female. She had no petechia or purpura at birth. But her platelet count was 55,000/mm3 and other laboratory findings were normal. On family history, the first baby had thrombocytopenia at birth too without petechia or other abnormal symptoms and his platelet count became spontaneously normal later. The mother's platelet count was normal and she had no history of idiopathic thrombocytopenic purpura(ITP) or bleeding tendency. Platelet crossmatching test showed positive between citric acid untreated paternal platelets and maternal serum, but negative to citric acid treated paternal platelets. These findings suggest maternal serum which contain anti-HLA antibodies to attack neonatal platelets and paternal platelets. Therefore this report documents a patient with neonatal thrombocytopenia induced by maternal anti HLA antibody.
Antibodies ; Antigens, Human Platelet ; Blood Platelets ; Citric Acid ; Female ; Hemorrhage ; Humans ; Parturition ; Platelet Count ; Purpura ; Rare Diseases ; Thrombocytopenia ; Thrombocytopenia, Neonatal Alloimmune*

Neonatal alloimmune thrombocytopenia(NAIT) is a rare disease caused by maternal alloimmunization against fetal platelet surface antigen, which is mainly platelet specific alloantigen or human leukocyte antigen(HLA). During routine hemotology, we accidentally discovered thrombocytopenia in a female fullterm newborn admitted due to jaundice. We excluded NAIT due to human platelet alloantigen(HPA), because the HPA of the mother and baby were the same on PCR-RFLP (polymerase chain reaction-restriction fragment length polymorphism). Mother's serum was tested for lyrnphocytotoxity against 36 donor lymphocytes, and anti-HLA A2, A24 and B58 were found. HLA typing of the father and baby revealed A2 antigen which was not present on the mothers lymphocytes. The patient received concentrated platelet and intravenous globulin. Her platelet count increased to 222,000/mm from 3,000/mm on the 11th day of life. We described a case of NAIT due to anti-HLA A2 antibody with a detailed clinical feature. (J Korean Pediatr Soc 1999;43:861-865)
Antigens, Surface ; Blood Platelets ; Fathers ; Female ; Histocompatibility Testing ; Humans ; Infant, Newborn ; Isoantigens ; Jaundice ; Leukocytes ; Lymphocytes ; Mothers ; Platelet Count ; Rare Diseases ; Thrombocytopenia ; Thrombocytopenia, Neonatal Alloimmune* ; Tissue Donors