Joosten E, Pelemans W, Devos P, Lesaffre E, Goossens W, Criel A, Verhaeghe R
Department of Internal Medicine, University Hospitals K.U. Leuven, Belgium.
Eur J Haematol. 1993 Jul;51(1):25-30. doi: 10.1111/j.1600-0609.1993.tb00600.x.
We prospectively studied 41 consecutive elderly patients with serum cobalamin (vitamin B12) levels lower than 125 pmol/l. The protein-bound cobalamin absorption test (PBAT) was performed in 34 of them and in 27 selected elderly control patients. The lower decision limit was 0.18% and an abnormal test was detected in only 9 (26%) of the 34 patients with low serum cobalamin level. When the PBAT was compared to the Schilling (Dicopac method) test, a concordant result was found in 80%. Serum methylmalonic acid and/or total homocysteine concentrations were elevated in 75% (26/35) of the patients with low serum cobalamin levels but also in 30% (5/17) of the control patients. Of the 12 and 9 cobalamin-deficient patients with elevated serum levels of methylmalonic acid and homocysteine, normalization after cobalamin therapy was obtained in 11 and 5 respectively. In conclusion, determination of serum metabolites and their response to cobalamin therapy are a sensitive index of significant cobalamin deficiency and a useful means of distinguishing between cobalamin and folate deficiency. The PBAT offers little advantage over the Schilling test in diagnosing cobalamin malabsorption in elderly patients.
我们前瞻性地研究了41例连续的血清钴胺素（维生素B12）水平低于125 pmol/l的老年患者。其中34例患者以及27例选定的老年对照患者进行了蛋白结合钴胺素吸收试验（PBAT）。下限为0.18%，在34例血清钴胺素水平低的患者中仅9例（26%）检测到试验异常。当将PBAT与希林试验（Dicopac法）进行比较时，80%的结果一致。血清钴胺素水平低的患者中有75%（26/35）血清甲基丙二酸和/或总同型半胱氨酸浓度升高，但对照患者中也有30%（5/17）升高。在血清甲基丙二酸和同型半胱氨酸水平升高的12例和9例钴胺素缺乏患者中，钴胺素治疗后分别有11例和5例恢复正常。总之，血清代谢物的测定及其对钴胺素治疗的反应是严重钴胺素缺乏的敏感指标，也是区分钴胺素缺乏和叶酸缺乏的有用方法。在诊断老年患者钴胺素吸收不良方面，PBAT与希林试验相比优势不大。
