Ogata T, Motohara K, Endo F, Kondo Y, Ikeda T, Kudo Y, Iribe K, Matsuda I
Department of Pediatrics, Kumamoto University Medical School, Japan.
Pediatrics. 1988 Mar;81(3):423-7.
Factor II coagulant antigen (FII-AG), the protein induced by vitamin K absence or antagonist II (PIVKA-II), and coagulant activity (normotest) were measured in low birth weight infants. The factor II coagulant antigen and normotest levels in one-day-old babies were lower than those of full-term infants (P less than .005, P less than .01, respectively). Infants whose normotest levels were less than 30% at one day (group A) received vitamin K2, and the others whose normotest levels were greater than 30% at one day (group B) were not treated. At this time, the mean factor II coagulant antigen level was significantly lower in group A than in group B (P less than .05). During the first seven days of life, in 65.2% of the infants in group B the PIVKA-II level became positive, but this did not occur in any infant in group A. After vitamin K treatment, there was greater improvement in the normotest level in infants with positive PIVKA-II levels than in those with negative PIVKA-II levels. This observation indicates that the hypoprothrombinemia found in low birth weight infants at one day of age is attributable to reduced synthesis of factor II coagulant antigen in the liver at this stage, but the prophylactic administration of vitamin K seemed to be effective even in such infants, probably because of the increase in factor II coagulant antigen synthesis (P less than .001) during the first seven days of life.
对低体重出生婴儿测定了凝血因子II促凝抗原（FII-AG）、维生素K缺乏或拮抗剂II诱导蛋白（PIVKA-II）以及促凝活性（正常试验）。一日龄婴儿的凝血因子II促凝抗原和正常试验水平低于足月儿（分别为P<0.005，P<0.01）。一日龄时正常试验水平低于30%的婴儿（A组）接受维生素K2治疗，而一日龄时正常试验水平高于30%的其他婴儿（B组）未接受治疗。此时，A组的平均凝血因子II促凝抗原水平显著低于B组（P<0.05）。在出生后的前七天，B组65.2%的婴儿PIVKA-II水平呈阳性，但A组无婴儿出现这种情况。维生素K治疗后，PIVKA-II水平呈阳性的婴儿的正常试验水平比PIVKA-II水平呈阴性的婴儿有更大改善。这一观察结果表明，低体重出生婴儿一日龄时出现的低凝血酶原血症归因于此时肝脏中凝血因子II促凝抗原合成减少，但维生素K的预防性给药即使在这类婴儿中似乎也有效，这可能是因为出生后的前七天内凝血因子II促凝抗原合成增加（P<0.001）。
