Afibrinogenemia Diagnosed During Pregnancy Successfully Managed with Targeted Cryoprecipitate Transfusion: A Case Report

BackgroundWe report a case of afibrinogenemia in a lady, which was detected for the first time during her pregnancy.CaseA 24-year-old G4A3 was referred as a case of vaginal bleeding, after a cervical cerclage at 14 weeks of gestation. Elastometry targeted correction of coagulopathy was done initially, and targeted cryoprecipitate transfusion was done to maintain her gestation. She underwent induced vaginal delivery at 34 weeks of gestation. Fourteen days postpartum, the mother and child were discharged home well.ConclusionCoagulation factor deficiency should be considered as a rare cause for RPL. Serum fibrinogen level of 50–100 mg/dl during pregnancy seems to be a safe and adequate target to maintain in pregnant patients with afibrinogenemia.     

β链基因突变导致遗传性无纤维蛋白原血症一例报告

目的检测1例遗传性无纤维蛋白原血症患者家系纤维蛋白原(Fg)基因突变。方法检测先证者及其家系成员血浆Fg^2 C及Fg的水平，从外周血单个核细胞中提取基因组DNA，PCR扩增Fg基因的所有外显子及侧翼内含子序列，检测其基因突变。结果发现先证者Fg基因共2处突变，FGB基因7972碱基处缺失G以及FGG基因2543碱基处的纯合T→A。结论FGG基因2543碱基处为多态位点，形成1144位氨基酸的I／K多态性。FGB基因7972碱基处缺失G，导致β链419位氨基酸之后的移码突变，形成了缺少最后27个氨基酸的截短的B链，后者可能是导致遗传性无纤维蛋白原血症的病理机制之一。FGB基因7972碱基处缺失G为国际首次发现的Fg基因突变。     

继发性纤维蛋白原减少症伴下肢静脉栓塞患者的护理

回顾性分析1例继发性纤维蛋白原减少症伴下肢静脉栓塞患者的临床表现与护理,总结此例患者的救治与护理经验:严密观察生命体征、出血情况、及时发现并处理并发症,保证静脉通路通畅,正确输注血制品,做好心理护理和肢体护理,使患者顺利好转出院.     

一种新的FGA基因无义突变导致遗传性无纤维蛋白原血症

目的　对 1例遗传性无纤维蛋白原血症患者及其家系成员进行基因分析,探讨遗传性无纤维蛋白原血症发病的分子机制。方法　凝血酶法与免疫比浊法测定血浆纤维蛋白原 (Fg)含量,提取先证者及其家系成员外周血基因组DNA,PCR法扩增其Fg的FGA、FGB和FGG基因所有外显子和侧翼序列,DNA序列分析Fg的基因异常。将先证者突变序列、家系成员和 50名正常人相应序列的PCR产物用限制性内切酶RsaⅠ消化,以进一步确定基因突变位点并排除基因多态性。结果　用Clauss法检测不到先证者及其父亲的血浆Fg,用免疫比浊法测定时,Fg含量均<0. 02g/L。两人FGA基因外显子 4第 3108位核苷酸发生C→T纯合性改变,使Fg的Aα链第 150位密码子 (CAG,编码Gln)突变为终止密码TAG。先证者及其父亲的FGA基因外显子 4和侧翼序列的PCR产物,不能被RsaⅠ酶切,其母亲及部分家系成员的PCR产物被部分酶切,而正常人和该家系中的 5个成员的PCR产物可被完全酶切。结论　FGA基因(外显子 4)Q150X无义突变导致该家系先证者及其父亲遗传性无Fg血症,家系中部分成员为携带者,此突变是一种国际上尚未报道的新的突变类型。     

遗传性低纤维蛋白原血症家系复合杂合基因缺陷的研究

目的 对1个遗传性低纤维蛋白原血症家系进行临床表型诊断和基因分析,并探讨该病的分子发病机制.方法 采集该家系3代共7人外周血,检测活化部分凝血活酶时间(APTT)、凝血酶原时间(PT)、凝血酶时间(TT)、蕲蛇酶时间(RT)、抗凝血酶活性(AT∶A)、蛋白C活性(PC∶A)和蛋白S活性(PS∶A),纤维蛋白原(Fg)抗原和活性分别用免疫比浊法和Clauss法测定;采用十二烷基磺酸钠-聚丙烯酰胺凝胶电泳(SDS-PAGE)对先证者及其父母的血浆纤维蛋白原进行半定量检测及肽链相对分子质量分析;使用自动校正凝血酶生成仪测定先证者的凝血酶生成;应用血栓弹力图仪检测血液凝固的动态过程和纤维蛋白形成过程的动力学变化.抽提先证者及家系成员外周血基因组DNA,采用PCR扩增Fg的3个基因(FGA、FGB和FGG)所有外显子及其侧翼序列,DNA直接测序进行基因分析.结果 先证者凝血功能检查显示Fg抗原为0.68 g/L,活性为0.48 g/L; TT延长为29.2 s,RT延长为75.8 s.SDS-PAGE结果显示,3条肽链相对分子质量正常,但含量明显减低;先证者凝血酶生成峰值为249.93 nmol/L,凝血酶生成潜力为1007.0 nmol·L-1·min;全血凝固的动态过程异常,凝血综合指数(CI)为-8.6,显示全血低凝状态.表型诊断为遗传性低纤维蛋白原血症.基因分析发现先证者纤维蛋白原Aa链存在g.3175A＞C突变导致的Gln143Pro突变,以及g·4642delC 突变导致的438位苏氨酸后编码26个异常氨基酸提前出现终止密码子;前者来源于母亲,后者来源于父亲.结论纤维蛋白原Aa链Gln143Pro和g.4642delC复合杂合突变是导致该家系先证者低纤维蛋白原血症的原因.     

Clinical and molecular characterization of Iranian patients with congenital fibrinogen disorders

IntroductionCongenital fibrinogen disorders (CFDs) are caused by mutations in the FGA, FGB and FGG genes and are classified as quantitative and qualitative fibrinogen defects. This study sought to determine the genetic background of CFDs in Iran and to examine the genotype-phenotype correlation.MethodsFourteen patients with a CFD diagnosis were included. Fibrinogen antigen and activity were measured by the immunoturbidimetric and Clauss methods respectively. Gene sequencing was performed following a polymerase chain reaction amplification of fibrinogen’s genes. The ISTH Bleeding Assessment Tool was also evaluated for all cases.ResultsPatients were diagnosed with dysfibrinogenemia (n = 10), hypodysfibrinogenemia (n = 2) and afibrinogenemia (n = 2). Seven different mutations located on FGA exon 2 (57 %), exon 4 (7%), exon 5 (7%) and FGG exon 8 (29 %) were identified. In patients with qualitative deficiencies, mutations were including p.Arg38Thr, p.Arg35His, p.Arg35Cys, p.Val145Asp, and p.Arg301Cys and were including p.Gly316GlufsX105 and p.Trp52stop in afibrinogenemic patients. In dysfibrinogenemia, two hotspot mutations, FGA Arg35 and FGG Arg301 were identified in 60 % of patients and the remaining (40 %) had p.Arg38Thr mutation. The p.Val145Asp and two hotspot mutations, p.Arg35His, p.Arg35Cys, were identified for the first time in Iran. The overall median (range) bleeding score (BS) was 4 (0-6) in all patients and it was 3.5 (0–5) in dysfibrinogenemia. Cutaneous bleeding and menorrhagia were the most common bleeding manifestations.ConclusionThere was a weak genotype-phenotype correlation in CFDs and patients with dysfibrinogenemia were more symptomatic than in previous studies. Despite ethnic’s differences, the prevalence of hotspot mutations in dysfibrinogenemia was similar to the other studies.     

FGG基因c.1073C>A突变致新生儿先天性纤维蛋白原缺乏症临床分析并文献复习

目的 探讨编码纤维蛋白原(Fg)γ多肽链基因-FGG突变,所致新生儿先天性纤维蛋白原缺乏症(CA)的临床及遗传学特点。方法 选择2021年5月,青岛大学附属医院新生儿科诊治的1例CA新生儿为研究对象,回顾性分析其临床病例资料。采用单基因病高通量测序技术,检测本例患儿外周血FGG基因,患儿父母进行特定基因位点的Sanger法测序,以明确患儿基因突变来源。对中国知网数据库、万方数据知识服务平台及PubMed数据库中,关于新生儿期起病的FGG基因突变所致CA病例进行检索,总结CA新生儿的临床及遗传学特点。本研究遵循的程序符合2013年修订的《世界医学协会赫尔辛基宣言》要求。监护人对患儿的诊治知情同意,并签署临床研究知情同意书。结果 (1)临床资料：本例患儿系女性,生后11.7 h时,因“发现面部淤斑4 h”入院,无发热,不伴其他部位出血等。除面部淤斑外,体格检查无异常。入院时凝血常规检查结果异常,主要为抗凝血酶Ⅲ与血浆Fg含量均较正常值低,分别为31.0%与0.18 g/L;凝血酶原时间与凝血酶时间均较正常值延长,分别为22.3 s与24.0 s。同时,患儿母亲于分娩前发现血浆Fg减少(为0...     

飞行员房间隔缺损合并原发性纤维蛋白原缺乏症一例

一、临床资料 患者，男性，26岁，歼击机飞行员，飞行时间240h，参加歼-7飞行不足10h。因继发孔型房间隔缺损就诊于我院。术前检查，凝血检查中纤维蛋白原（fibrinogen，FIB）量明显降低，多次检查均在0．22～0．26g／L之间，其他3项指标凝血酶原时间（prothrombin time，PT）、     

Increased prothrombin activation in a patient with congenital afibrinogenemia is reversible by fibrinogen substitution

We describe a patient with congenital afibrinogenemia who showed elevated prothrombin activation fragments (F₁₊₂) indicating increased thrombin formation. This finding was unexpected since it has hitherto been thought that patients with congenital hypo- or afibrinogenemia have no evidence of increased utilization or accelerated consumption of coagulation factors. No other possible reasons for the elevation of F₁₊₂ were found. Upon fibrinogen substitution F₁₊₂ decreased and were again increasing when fibrinogen concentration in plasma fell to very low levels. These findings raise the question of whether increased thrombin formation should be understood as a compensatory mechanism in congenital afibrinogenemia.