De Paz R, Hernández-Navarro F
Servicio de Hematología y Hemoterapia Hospital Universitario La Paz Madrid.
Nutr Hosp. 2005 Nov-Dec;20(6):433-5.
Pernicious anemia is the most frequent cause of megaloblastic anemia in our area, and it is the result of a vitamin B12 deficiency due, itself, to the decrease or absence of intrinsic factor (IF) because of gastric mucosa atrophy or autoimmune destruction of IF-producing parietal cells. With the existence of a severe gastric atrophy, there is a decrease in acid and IF production and a further change in vitamin B12 absorption. Fifty percent of the cases are associated to anti-IF antibodies, which presence in other autoimmune diseases is exceptional. In patients with pernicious anemia, measurement of anti-IF antibodies has high specificity (95%); however, measurement of anti-parietal cells antibodies has low specificity. The first-choice treatment is administration of vitamin B12 intramuscularly. The regimen is the administration of 1 mg of vitamin B12 daily for one week, weekly thereafter for one month and, then, every 2-3 months for life.
恶性贫血是我们地区巨幼细胞贫血最常见的病因，它是由于胃黏膜萎缩或产生内因子（IF）的壁细胞发生自身免疫性破坏，导致内因子减少或缺乏，进而引起维生素B12缺乏的结果。存在严重胃萎缩时，胃酸和内因子分泌减少，维生素B12吸收进一步改变。50%的病例与抗内因子抗体有关，这种抗体在其他自身免疫性疾病中很少见。在恶性贫血患者中，抗内因子抗体检测具有较高的特异性（95%）；然而，抗壁细胞抗体检测的特异性较低。首选治疗方法是肌肉注射维生素B12。治疗方案为：每天肌肉注射1毫克维生素B12，连续注射一周，之后每周注射一次，持续一个月，然后每2至3个月注射一次，终身维持。
