Veda P
Department of Pathology, ESI PGIMSR, Rajajinagar, Bangalore, India ; No-10, Sri Devi Krupa, 1st main, 1st block, RT Nagar, Bangalore, 560032 India.
Indian J Hematol Blood Transfus. 2013 Mar;29(1):26-30. doi: 10.1007/s12288-011-0142-7. Epub 2012 Feb 8.
Macrocytosis, a condition in which erythrocytes are larger than normal manifests as an increase in mean corpuscular volume (MCV) more than 100 fl. The aim of this study was to identify the underlying causes of macrocytosis, detected in routine hemograms and to evaluate the hematological features in different etiologies. This study included 178 adult patients whose detailed medical history was recorded, and Vitamin B12 assay, folate assay, thyroid function tests, liver function tests, complete blood counts and peripheral smear evaluation was performed. Alcoholism was identified as the etiological factor in 65 cases (36.5%), Vitamin B12 deficiency in 43 cases (24.1%) and drug related in 23 cases (12.9%). These three conditions accounted for 73.6% of macrocytosis. Other causes identified were folate deficiency, liver disease, Myelodysplastic syndrome, chronic renal failure and Aplastic anemia. In 41 cases, the cause of macrocytosis could not be explained. Anemia was observed in 95 cases (53.3%) being most common in Vitamin B12 deficiency. 9 cases (20.9%) of Vitamin B12 deficiency presented with isolated macrocytosis without anemia. It was observed that mean hemoglobin was lower and red cell distribution width (RDW) higher in megaloblastic conditions. Peripheral smear revealed hypersegmented neutrophils in 86% and macro-ovalocytes in 72% of the megaloblastic cases. Complete medical history, red cell parameters and peripheral blood smear are simple, inexpensive tools which assist in identifying the underlying cause of macrocytosis, particularly in resource limited settings. Macrocytosis needs to be evaluated even in the absence of anemia, as it may be the first clue to an underlying pathology.
大细胞性贫血是一种红细胞大于正常大小的病症，表现为平均红细胞体积（MCV）超过100飞升。本研究的目的是确定在常规血常规检查中检测到的大细胞性贫血的潜在病因，并评估不同病因的血液学特征。本研究纳入了178例成年患者，记录了他们详细的病史，并进行了维生素B12检测、叶酸检测、甲状腺功能测试、肝功能测试、全血细胞计数和外周血涂片评估。65例（36.5%）患者的病因是酒精中毒，43例（24.1%）是维生素B12缺乏，23例（12.9%）与药物有关。这三种情况占大细胞性贫血病例的73.6%。确定的其他病因包括叶酸缺乏、肝脏疾病、骨髓增生异常综合征、慢性肾衰竭和再生障碍性贫血。41例患者的大细胞性贫血病因无法解释。95例（53.3%）患者出现贫血，其中维生素B12缺乏最为常见。9例（20.9%）维生素B12缺乏患者表现为单纯大细胞性贫血而无贫血。观察到巨幼细胞性贫血患者的平均血红蛋白较低，红细胞分布宽度（RDW）较高。外周血涂片显示，86%的巨幼细胞性贫血病例出现多分叶核中性粒细胞，72%出现大卵圆形红细胞。完整的病史、红细胞参数和外周血涂片是简单、廉价的工具，有助于确定大细胞性贫血的潜在病因，尤其是在资源有限的环境中。即使在没有贫血的情况下，也需要对大细胞性贫血进行评估，因为它可能是潜在病理状况的首个线索。
