Khanduri Uma, Sharma Archna, Joshi Arti
Department of Haematology, St Stephen's Hospital, Tis Hazari, New Delhi, India.
Natl Med J India. 2005 Jul-Aug;18(4):182-3.
Our aim was to assess cobalamin and folate levels in normal Indian subjects before undertaking a prospective study of megaloblastic anaemia.
We took samples from 25 men and 25 women to establish the normal range. The exclusion criteria for subjects were age below 18 years and above 65 years, haemoglobin < 12 g/dl, and those who were pregnant, lactating or on any medication including vitamin supplements. A complete blood count and blood film examination for hypersegmented neutrophils were done. Serum cobalamin and folate assays were performed by a competitive immunoassay. The reference range supplied with the kits for serum cobalamin was 100-700 pg/ml and for serum folate it was 3-22 ng/ml.
Since many 'normal' subjects in the sample showed values below the normal reference range, the numbers sampled were increased to 46 men and 50 women. Of all the subjects tested, 46.9% had subnormal values of one of the two vitamins. The normal ranges for serum cobalamin established in this study were--men 100-388 pg/ml and women 105.3-434 pg/ml. Of the 46 men tested, 17 (36.9%) had low cobalamin levels and of the 50 women tested, 23 (46%) had low cobalamin levels. Levels < 50 pg/ml were seen in 46.9% of these subjects. The normal ranges for serum folate in the study were--men 3.1 to > 22 ng/ml, women 3-12.26 ng/ml. In the study group, 8 men (17.3%) and 6 women (12%) had folate deficiency. Eight subjects (17%) had combined deficiency of the two vitamins. The mean corpuscular volume was not informative and was elevated in only 1 subject. Hypersegmentation of neutrophils was present in 75% of deficient subjects.
We established normal levels for serum cobalamin and folate in our study group. Of the subjects studied, 46.9% had subnormal levels of serum cobalamin or serum folate, cobalamin deficiency being five times more common than folate. Hypersegmentation of neutrophils was a better indicator of occult megaloblastosis than the mean corpuscular volume.
我们的目的是在对巨幼细胞贫血进行前瞻性研究之前，评估正常印度受试者的钴胺素和叶酸水平。
我们从25名男性和25名女性中采集样本以确定正常范围。受试者的排除标准为年龄低于18岁和高于65岁、血红蛋白<12 g/dl，以及怀孕、哺乳或正在服用包括维生素补充剂在内的任何药物的人。进行了全血细胞计数和血涂片检查以检测分叶过多的中性粒细胞。血清钴胺素和叶酸检测采用竞争性免疫测定法。试剂盒提供的血清钴胺素参考范围为100 - 700 pg/ml，血清叶酸参考范围为3 - 22 ng/ml。
由于样本中的许多“正常”受试者显示的值低于正常参考范围，因此采样人数增加到46名男性和50名女性。在所有测试的受试者中，46.9%的人两种维生素之一的值低于正常水平。本研究确定的血清钴胺素正常范围为——男性100 - 388 pg/ml，女性105.3 - 434 pg/ml。在46名测试男性中，17名（36.9%）钴胺素水平低，在50名测试女性中，23名（46%）钴胺素水平低。这些受试者中有46.9%的人水平<50 pg/ml。本研究中血清叶酸的正常范围为——男性3.1至>22 ng/ml，女性3 - 12.26 ng/ml。在研究组中，8名男性（17.3%）和6名女性（12%）有叶酸缺乏。8名受试者（17%）有两种维生素的联合缺乏。平均红细胞体积无参考价值，仅1名受试者升高。75%的缺乏受试者存在中性粒细胞分叶过多。
我们在研究组中确定了血清钴胺素和叶酸的正常水平。在研究的受试者中，46.9%的人血清钴胺素或血清叶酸水平低于正常，钴胺素缺乏比叶酸缺乏常见五倍。中性粒细胞分叶过多比平均红细胞体积更能准确反映潜在的巨幼细胞病变。
