PDF(Pubmed)
Abstract：
Vitamin B12 deficiency is a significant public health problem globally. Although it is a well-known cause of macrocytic anaemia and in advanced cases, pancytopenia, there remains a relative paucity of cases reported in pregnancy. It is associated with an increased risk of pregnancy complications and adverse birth outcomes such as neural tube defects, preterm birth, low birth weight, neurological sequelae and intrauterine death. It has a predilection for individuals aged >60 years. It has been implicated in a spectrum of neuropsychiatric disorders and it may also exert indirect cardiovascular effects. Severe vitamin B12 deficiency may present with haematological abnormalities that mimic thrombotic microangiopathy such as HELLP syndrome (haemolysis, elevated liver enzymes and low platelets) or it may present as pseudothrombotic microangiopathy (Moschcowitz syndrome) characterised by anaemia, thrombocytopenia and schistocytosis. It can also closely mimic thrombotic thrombocytopenia purpura, hence posing a diagnostic challenge to the unwary physician. Serological measurement of vitamin B12 levels confirms the diagnosis. Oral supplementation with vitamin B12 remains a safe and effective treatment. The authors describe the case of a multiparous woman in her late 20s presenting with a plethora of non-specific symptoms at 29+5 weeks\' gestation. Her haemoglobin was 45 g/L, platelets 32×109/L, vitamin B12 <150 ng/L and serum folate <2 µg/L. She was not a vegetarian, but her diet lacked nutrition. Following parenteral B12 supplementation, her haematological parameters improved. The pregnancy was carried to term. Due to the plethora of non-specific symptoms, the diagnosis can be challenging to establish. Adverse maternal or fetal outcomes may occur. Folic acid supplementation may mask an occult vitamin B12 deficiency and further exacerbate or initiate neurological disease.
摘要：
维生素B12缺乏是全球性的重大公共卫生问题。尽管这是众所周知的大细胞性贫血的原因，但在晚期病例中，全血细胞减少症,怀孕期间报告的病例相对较少。它与妊娠并发症和不良分娩结局如神经管缺陷的风险增加有关，早产,低出生体重,神经后遗症和宫内死亡。它倾向于年龄>60岁的人。它与一系列神经精神疾病有关，也可能产生间接的心血管作用。严重的维生素B12缺乏可能表现为模拟血栓性微血管病的血液学异常，如HELLP综合征（溶血，肝酶升高和血小板低）或可能表现为以贫血为特征的假性血栓性微血管病（Moschcowitz综合征），血小板减少症和血吸虫病。它还可以紧密模拟血栓性血小板减少性紫癜，因此对粗心的医生提出了诊断挑战。维生素B12水平的血清学测量证实了诊断。口服补充维生素B12仍然是一种安全有效的治疗方法。作者描述了一名20多岁的多胎妇女在妊娠29+5周时表现出过多的非特异性症状。她的血红蛋白是45克/升,血小板32×109/L，维生素B12<150ng/L，血清叶酸<2µg/L。她不是素食主义者,但她的饮食缺乏营养.肠胃外补充B12后，她的血液学参数有所改善。怀孕一直持续到足月。由于大量的非特异性症状，诊断可能具有挑战性。可能发生不良的母体或胎儿结局。补充叶酸可能掩盖隐匿性维生素B12缺乏，并进一步加剧或引发神经系统疾病。
