Tadakamalla Ashvin K, Talluri Siva K, Besur Siddesh
Department of Internal Medicine, Michigan State University Internal Medicine Residency Program, McLaren Regional Medical Center, Flint, Michigan, USA.
N Am J Med Sci. 2011 Oct;3(10):472-4. doi: 10.4297/najms.2011.3472.
Schistocytes are fragmented red blood cells due to the flow of blood through damaged capillaries and indicate endothelial injury. They are typical of microangiopathic hemolytic anemia seen in life threatening conditions like disseminated intravascular coagulation or thrombotic thrombocytopenic purpura/hemolytic uremic syndrome .We report a rare sub-acute presentation of pernicious anemia with hemolysis, thrombocytopenia and numerous schistocytes that was initially diagnosed as a more serious thrombotic thrombocytopenic purpura.
A 31-year-old Caucasian woman presented with fatigue and paresthesia of both feet for 1 week. Past medical history included hypertension and gastro-esophageal reflux disease. Examination revealed scleral icterus and pallor. Examination of the abdomen did not show hepatosplenomegaly. Initial laboratory tests showed severe anemia, and low platelets. Indirect bilirubin and serum Lactate De Hydrogenase were elevated. Prothrombin time, partial thromboplastin time, serum fibrinogen, and serum fibrin degradation product levels were normal. Peripheral smear revealed numerous schistocytes, anisocytosis and macro-ovalocytes. Thrombotic thrombocytopenic purpura (TTP) was suspected due to the constellation of sub-acute onset of fatigue and paresthesia along with thrombocytopenia, schistocytes and an elevated LDH. Plasmapheresis was initiated for possible TTP. However, platelet count worsened despite plasmapheresis for 4 days. On re-evaluation, vitamin B(12) was found to be low. Treatment with intra-muscular vitamin B(12) led to symptomatic and hematologic improvement. Pernicious anemia was confirmed by the presence of anti-intrinsic factor antibodies, elevated serum gastrin level and atrophic gastritis.
Clinicians must be aware of unusual clinical presentation of vitamin B(12) deficiency with schistocytes as the management is simple and effective.
裂体细胞是由于血液流经受损毛细血管而破碎的红细胞，提示内皮损伤。它们是在诸如弥散性血管内凝血或血栓性血小板减少性紫癜/溶血尿毒综合征等危及生命的疾病中所见的微血管病性溶血性贫血的典型表现。我们报告了一例罕见的恶性贫血亚急性表现，伴有溶血、血小板减少和大量裂体细胞，最初被诊断为更严重的血栓性血小板减少性紫癜。
一名31岁的白人女性因疲劳和双足感觉异常1周就诊。既往病史包括高血压和胃食管反流病。检查发现巩膜黄染和面色苍白。腹部检查未发现肝脾肿大。初始实验室检查显示严重贫血和血小板减少。间接胆红素和血清乳酸脱氢酶升高。凝血酶原时间、部分凝血活酶时间、血清纤维蛋白原和血清纤维蛋白降解产物水平正常。外周血涂片显示大量裂体细胞、红细胞大小不均和巨椭圆红细胞。由于疲劳和感觉异常亚急性发作、血小板减少、裂体细胞和乳酸脱氢酶升高的综合表现，怀疑为血栓性血小板减少性紫癜。开始进行血浆置换以治疗可能的血栓性血小板减少性紫癜。然而，尽管进行了4天的血浆置换，血小板计数仍恶化。再次评估时，发现维生素B12水平低。肌肉注射维生素B12治疗后症状和血液学指标得到改善。抗内因子抗体的存在、血清胃泌素水平升高和萎缩性胃炎证实了恶性贫血。
临床医生必须意识到维生素B12缺乏伴有裂体细胞的不寻常临床表现，因为其治疗简单有效。
