Cases Of Alloimmune Thrombocytopenia Research Articles

Thrombocytopenia during the First Week of Life among Neonates with Down Syndrome: Data from Multihospital Healthcare Systems

Background: A fault in chromosome distribution during cell division leads to aneuploidy, which can be associated with thrombocytopenia. Various hematological abnormalities have been reported among neonates with Down syndrome (DS). Neutrophilia, thrombocytopenia and polycythemia were the most common hematological abnormalities observed among neonates with Down syndrome. In particular, thrombocytopenia below 150×109/L was found approximately in two-third of DS and 6% of counts below 50,000 was detected during the first week of life.The exact mechanism remains unknown, but is thought to be due to decreased platelet production from chronic fetal hypoxia. fetal hypoxia also leads to intrauterine growth retardation and suboptimal response of thrombopoitin system (TPO) to thrombocytopenia in DS during the neonatal period. Few cases of alloimmune thrombocytopenia with DS due to anti-HPA antibody were reported.Methods: Data from multihospital healthcare systems shows large two case series of infants with cytogenetically confirmed DS and a reference group infants without birth defects all born during the period 2009-2015. During this period, 145,522 live births were recorded at 18 hospitals. Down syndrome was recognized in 226 newborn (1 in 644). Data were analyzed using multivariate logistic regression analysis expressed as adjusted odds ratio (aORs) with 95% confidence intervals (95% CIs).Results & Conclusion: Infants with DS had a significantly higher risk for thrombocytopenia (aOR = 32.4). Platelet counts in DS averaged 104600 per microliter. The mean platelet volume did not correlate with the platelet count, but tended to run slightly large (9.2 +/- 1.3 fl). Persistence of thrombocytopenia beyond 8 to 12 weeks after birth should warrant a hematology consult. Thrombocytopenia can be seen associated with some types of congenital heart defects. Karyotype testing should be done in all obviously dysmorphic infants with thrombocytopenia. It seems reasonable to recommend that one or more CBCs be obtained on all neonates with Down syndrome.

A Case of Alloimmune Thrombocytopenia, Hemorrhagic Anemia-Induced Fetal Hydrops, Maternal Mirror Syndrome, and Human Chorionic Gonadotropin-Induced Thyrotoxicosis

Fetal/neonatal alloimmune thrombocytopenia (FNAIT) can be a cause of severe fetal thrombocytopenia, with the common presentation being intracranial hemorrhage in the fetus, usually in the third trimester. A very unusual case of fetal anemia progressed to hydrops. This was further complicated by maternal Mirror syndrome and human chorionic gonadotropin–induced thyrotoxicosis. Without knowledge of etiology, and possibly due to associated cardiac dysfunction, fetal transfusion resulted in fetal demise. Subsequent testing revealed FNAIT as the cause of severe hemorrhagic anemia. In cases with fetal anemia without presence of red blood cell antibodies, FNAIT must be ruled out as a cause prior to performing fetal transfusion. Fetal heart may adapt differently to acute hemorrhagic anemia compared with a more subacute hemolytic anemia.

Intrauterine fetal transfusion for red-cell alloimmunisation: a single-centre study over 15 years

ObjectiveTo examine perinatal outcomes following intrauterine fetal transfusion (IUT), in a single tertiary fetal medicine unit over a 15-year period.Study designA retrospective analysis of women undergoing IUT in the National...

Clinical and diagnostic comparison of neonatal alloimmune thrombocytopenia to non-immune cases of thrombocytopenia

Affected patients with neonatal alloimmune thrombocytopenia (AIT) are often severely thrombocytopenic and, if so, may suffer an intracranial hemorrhage (ICH). This study was undertaken to compare the outcome of cases of AIT to cases of neonatal thrombocytopenia shown not to be AIT and to identify clinical features that would facilitate the diagnosis. Two hundred twenty two cases of neonatal thrombocytopenia for which serologic testing was obtained by the referring physician were accrued for this study from 11 testing laboratories. The relevant clinical information was pursued. The mean birth platelet count in 110 neonates with AIT was 26,000/mm(3) x 10(9)/L and the rate of ICH was 11% (not all neonates had head sonos). Three criteria distinguished cases of AIT from other causes of neonatal thrombocytopenia (n = 56): (1) severe thrombocytopenia <50,000/mm(3) x 10(9)/L; (2) ICH associated with 1 or more of: a 1-min Apgar score >5, birthweight >2,200 g, grade >1, antenatal occurrence, or signs of bleeding, that is, petechiae, ecchymoses; and (3) no additional, non-hemorrhagic neonatal medical problems. AIT is a unique type of neonatal thrombocytopenia with significant hemorrhagic consequences. Identification of AIT at the bedside should guide institution of appropriate treatment and lead to serologic testing for confirmation.

Anti-HPA-3A induces severe neonatal alloimmune thrombocytopenia

Objective: Fetal and neonatal alloimmune thrombocytopenia (AIT) caused by feto-maternal incompatibility at the HPA-1a (PLA-1) locus is well characterized. Alloimmunization and disease caused by HPA-3a is rare. Study design: We conducted a retrospective analysis of all known cases of AIT caused by HPA-3a incompatibility identified at 3 major reference laboratories from 1986 to 1996. Platelet antigen typing and antibody specificity were determined by serologic evaluation. In some cases confirmatory genotyping was performed. Results: Fourteen cases of anti-HPA-3a-induced AIT in 11 families were identified. Five patients had a previous affected sibling, and 2 cases were firstborn children. All patients had severe thrombocytopenia at birth (platelet count <20 × 109/L). Regardless of therapy, the median time to platelet recovery was 6 days (range, 3 to 23 days). Two (15%) patients had documented intracranial hemorrhage, 1 with severe sequelae including apnea and convulsions. A literature review describing 16 additional patients corroborates the finding of severe thrombocytopenia and a significant incidence of intracranial hemorrhage caused by HPA-3a incompatibility. Conclusion: AIT caused by incompatibility of HPA-3a is similar in severity to disease caused by incompatibility of HPA-1a. Affected families should be appropriately counseled and considered for antenatal therapy. (J Pediatr 2001;138:862-7)

The Sonographic Detection of Intracranial Hemorrhage Due to Alloimmune Thrombocytopenia

Alloimmune thrombocytopenia is a rare condition in which antibodies from the mother's circulation cross the placenta and destroy the platelets in the fetus. Approximately 14% of affected fetuses or neonates develop intracranial hemorrhage, leading to death or long-term central nervous system disabilities. After treating two such cases, 26 previously reported cases of alloimmune thrombocytopenia with intracranial hemorrhage were examined to discover if these hemorrhages exhibit a typical sonographic appearance, course, and time of hemorrhage. When intracranial hemorrhage occurs in cases of alloimmune thrombocytopenia, it has a typical appearance in 76% of cases: a large hematoma in the center of the cerebral hemisphere. There is no difference between genders in the occurrence of alloimmune thrombocytopenia unless hemorrhage occurs: 72% of neonates with alloimmune thrombocytopenia and intracranial hemorrhage are male. Intracranial hemorrhage occurs before labor and delivery in 76% of cases. Sonographers cannot depend on a history of the condition in previous pregnancies as an indication of alloimmune thrombocytopenia: only 35% of neonates with alloimmune thrombocytopenia and hemorrhage have previously affected siblings.

Antenatal treatment of fetal alloimmune cytopenias.

The antenatal use of intravenous immunoglobulin (IVG) was explored in 9 cases of alloimmune cytopenias affecting fetuses. In 7 cases of alloimmune thrombocytopenia, IVG at a dose of 1 gm/kg/week appeared to be uniformly effective in elevating the fetal platelet count and preventing a recurrence of antenatal intracranial hemorrhage (2 cases). In 2 cases of Rh disease the results were more equivocal. There did not appear to be any significant toxicity associated with its use. The mechanism of IVG effect in the successfully treated cases remains uncertain.