Key Points• The systematic review suggests that first-line antenatal management in FNAIT is weekly IVIG administration.• Noninvasive management is effective without the relatively high rate of adverse outcomes seen in invasive strategies.Several strategies can be used to manage fetal or neonatal alloimmune thrombocytopenia (FNAIT) in subsequent pregnancies. Serial fetal blood sampling (FBS) and intrauterine platelet transfusions (IUPT), as well as weekly maternal IV immunoglobulin infusion (IVIG), with or without additional corticosteroid therapy, are common options, but optimal management has not been determined. The aim of this systematic review was to assess antenatal treatment strategies for FNAIT. Four randomized controlled trials and 22 nonrandomized studies were included. Pooling of results was not possible due to considerable heterogeneity. Most studies found comparable outcomes regarding the occurrence of intracranial hemorrhage, regardless of the antenatal management strategy applied; FBS, IUPT, or IVIG with or without corticosteroids. There is no consistent evidence for the value of adding steroids to IVIG. FBS or IUPT resulted in a relatively high complication rate (consisting mainly of preterm emergency cesarean section) of 11% per treated pregnancy in all studies combined. Overall, noninvasive management in pregnant mothers who have had a previous neonate with FNAIT is effective without the relatively high rate of adverse outcomes seen with invasive strategies. This systematic review suggests that first-line antenatal management in FNAIT is weekly IVIG administration, with or without the addition of corticosteroids. (Blood. 2017;129(11):1538-1547
Fetal and neonatal alloimmune thrombocytopenia (FNAIT) may result in severe bleeding, particularly fetal and neonatal intracranial haemorrhage (ICH). As a result, FNAIT requires prompt identification and treatment; subsequent pregnancies need close surveillance and management. An international panel convened to develop evidence-based recommendations for diagnosis and management of FNAIT. A rigorous approach was used to search, review and develop recommendations from published data for: antenatal management, postnatal management, diagnostic testing and universal screening. To confirm FNAIT, fetal human platelet antigen (HPA) typing, using non-invasive methods if quality-assured, should be performed during pregnancy when the father is unknown, unavailable for testing or heterozygous for the implicated antigen. Women with a previous child with an ICH related to FNAIT should be offered intravenous immunoglobulin (IVIG) infusions during subsequent affected pregnancies as early as 12 weeks gestation. Ideally, HPA-selected platelets should be available at delivery for potentially affected infants and used to increase the neonatal platelet count as needed. If HPA-selected platelets are not immediately available, unselected platelets should be transfused. FNAIT studies that optimize antenatal and postnatal management, develop risk stratification algorithms to guide management and standardize laboratory testing to identify high risk pregnancies are needed.
Haemophilia A (HA) is an X-linked bleeding disorder caused by diverse mutations in the human coagulation factor VIII (FVIII) gene. We have analysed DNA from 109 unrelated Indian patients with HA for their FVIII gene defects. Among these patients 89 (82%) had severe (FVIII:C <1%) HA, 11 (10%) had moderate (FVIII:C 1-5%) HA and nine (8%) had mild (FVIII:C 5-30%) HA. These patients were first screened for the common intron 22 and intron 1 inversions. Inversion negative samples were screened for point mutations by a multiplex PCR and conformation sensitive gel electrophoresis strategy. Mutations were identified in 101 of the 109 patients. These included two (2%) intron 1 and 51 (51%) intron 22 inversions, four (4%) gross deletions and 44 (43%) point mutations. Twenty-nine novel causative mutations, including 11 missense, seven frameshift, five nonsense mutations, three splice site defects and three gross deletions were detected. Ten of the novel missense mutations were studied by molecular modelling. Two different (Thr2253Pro and Pro1392fs) mutations were seen in four unrelated families and FVIII gene haplotyping suggested a common founder effect. Seven of these 109 patients had inhibitors. Among them, four had intron 22 inversions, one had a novel gross deletion (delexon 2-9) and one a nonsense mutation (Trp1535Stop). In one of these patients, no mutation could be identified in the FVIII gene. A Thr2253Pro novel mutation and an intron 22 inversion were identified in two female haemophiliacs. The data from this study suggests that the spectrum of gene defects in Indian patients with HA is as heterogeneous as reported in other populations.
Data on the clinical manifestations of patients with clotting factor defects other than Haemophilia A, B and von Willebrand disease are limited because of their rarity. Due to their autosomal recessive nature of inheritance, these diseases are more common in areas where there is higher prevalence of consanguinity. There is no previous large series reported from southern India where consanguinity is common. Our aim was to analyze clinical manifestations of patients with rare bleeding disorders and correlate their bleeding symptoms with corresponding factor level. Data were collected in a standardized format from our centre over three decades on 281 patients who were diagnosed with rare bleeding disorders (fibrinogen, prothrombin, factor V (FV), FVII, FX, FXI, FXIII and combined FV or FVIII deficiency). Patients with liver dysfunction or those on medications which can affect factor level were excluded. All patients with <50% factor levels were included in this analysis. Patients were analysed for their salient clinical manifestations and it was correlated with their factor levels. The data shows that FXIII deficiency is the commonest and FXI deficiency is the rarest in Southern India. There was no significant difference in bleeding symptoms among those who were < or >1% factor coagulant activities among all disorders, except for few symptoms in FVII and FX deficiency. An international collaborative study is essential to find out the best way of classifying severity in patients with rare bleeding disorders.
Summary. The previously described South African type a-thalassaemia-1 mutation was identified in Indian HbH patients using a polymerase chain reaction (PCR) strategy. A multiplex PCR assay was devised to detect heterozygotes and homozygotes. This a-thalassaemia-1 mutation was found to be the commonest determinant causing HbH disease in this population. In one family this mutation was found in combination with a novel splice donor mutation a2 IVS I-1 (G fi A). Characterization of the breakpoint junction sequence revealed, in addition to a 23 kb deletion, that there was an addition of 160 bp bridging the breakpoints. Similar to other deletions in the a-globin gene cluster, there is an Alu repeat-mediated mechanism for the origin of the deletion. Keywords: a-thalassaemia, PCR, India, AluThe a-thalassaemias are genetic defects characterized by the decrease or complete suppression of synthesis of the a-globin polypeptide chains of haemoglobin. They are the most common single-gene diseases in the world. The a-globin genes are duplicated (a1 and a2) and located within the a gene cluster f2)wf1)wa2)wa1)a2)a1)h1 on the distal short arm region of chromosome 16 (Higgs et al, 1989). This cluster contains four genes and three pseudogenes. Deletions of one ()a) or both () ) )) of these cis-linked genes are the most common causes of the a-thalassaemias. Around 25 different two-gene cis deletions () )) and eight single-gene deletions ()a)
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