A method for the colorimetric determination of urinary methylmalonic acid in pernicious anemia.
A method for the colorimetric determination of urinary methylmalonic acid in pernicious anemia.
复制标题
比色测定恶性贫血尿甲基丙二酸的方法。
DOI：
10.5555/uri:pii:0022214365900508
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发表时间：
1965
期刊：
影响因子：
--
通讯作者：
G. Plaut
中科院分区：
文献类型：
--
作者：
A. J. Giorgio;G. Plaut
尿中甲基丙二酸的检测可作为诊断维生素B 12缺乏症（包括恶性贫血）的有用工具。本文介绍了一种简便的测定方法。用Dowex 3 × 4阴离子交换树脂从尿中分离出酸，使其与重氮化对硝基苯胺反应生成绿色，在620 mμ处用比色法测定。检查了许多尿液成分，发现其对测定无显著干扰。本文报告一位未经治疗的恶性贫血病人的尿液，经纸层析及薄层层析法，鉴定出甲基丙二酸为显色剂。丙二酸，也与重氮试剂产生绿色颜色，在该尿液中未检出。该患者的尿甲基丙二酸水平升高显示对治疗的迅速反应，从750 mg下降。92毫克。在肠胃外给予维生素B 12后的24小时内每天给予。研究的另外两名恶性贫血患者显示治疗前水平为40和610 mg。甲基丙二酸。在含有72至1，020毫克的尿样中，该方法的变异系数为4%至15%。甲基丙二酸/升。在表观浓度为5 mg时，误差明显更大。甲基丙二酸的含量。
Abstract The detection of increased methylmalonic acid in the urine serves as a useful tool in the diagnosis of vitamin B 12 deficiencies, including pernicious anemia. A simple method for determination is described here. The acid is isolated from urine by using Dowex 3 × 4 anion-exchange resin, allowed to react with diazotised p-nitroaniline to form a green color, and determined spectrophotometrically at 620 mμ. A number of urinary components were examined and found not to interfere significantly with the assay. Methylmalonic acid was identified by paper and thin-layer chromatography as the chromogenic agent in the urine of a patient with untreated pernicious anemia. Malonic acid, which also yields a green color with the diazo reagent, was not detectable in this urine. The elevated level of urinary methylmalonic acid in this patient showed a prompt response to therapy, declining from 750 mg. to 92 mg. per day within a 24 hour period following the parenteral administration of vitamin B 12 . Two other patients with pernicious anemia who were studied showed pretreatment levels of 40 and 610 mg. methylmalonic acid per day. The coefficient of variation for the method ranged from 4 to 15 per cent in urine samples containing from 72 to 1,020 mg. methylmalonic acid per liter. The error was considerably greater at the apparent concentration of 5 mg. of methylmalonic acid per liter in normal urine.