正常孕妇纤维蛋白原使用不同参考值范围的临床差异

The clinical differences of choosing different fibrinogen reference intervals for normal pregnancy

目的探讨正常孕妇Fg参考值范围的临床价值。方法分别使用原Fg参考值（一般人群）以及现用的孕期相关的孕妇Fg参考值，对Sysmex CA-7000全自动血凝仪检测的12423名正常孕妇早、中、晚孕或产后的Fg结果进行分析和比较。校准并且每日质控合格后检测临床标本。原Fg参考值范围参照《临床检验基础》（第4版）标准，现用％参考值为本实验室利用纵向序贯研究所建正常孕妇各孕期Fg参考值。对两参考值范围进行一致性检验，计算Kappa值。结果原Fg参考值范围为2．00～4．00g／L，现用正常孕妇早、中、晚孕及产后各孕期如参考值范围分别为2．73～4．93、2．94～5．00、3．01～5．98、1．76～3．60g／L。相比于原Fg参考值范围，使用现用Fg参考值范围异常率降低到1／4，经一致性检验，Kappa=0．128，Kappa〈0．4，U=26．825，P〈0．05，两参考值范围判断标准一致性较差；对表现不一致的对象进一步分析，高／低于原Fg参考范围而现用Fg参考范围正常的共6270名，占50．47％，说明现用参考值大幅度降低了因Fg生理性增高而导致的异常判断，降低“误诊率”；原Fg参考范围正常而高／低于现用Fg参考范围的共323名，占2．60％，其中低于现用Fg参考范围303名，说明现用参考值增加了低Fg水平异常判断的敏感性，降低“漏诊率”。结论从经济角度考虑，现用Fg参考值范围更适用、经济；从应用角度考虑，现用心参考值范围评价个体危险性的敏感性增加。

Objective To investigate the clinical value of fibrinogen reference intervals in normal pregnant women. Methods We analyzed and compared fibrinogen results from 12 423 cases of normal pregnant women through previous and present reference intervals. All the results were obtained from a calibrated and Qc qualified Sysmex CA-7000 automatic coagulometer. The previous fibrinogen reference interval was from Clinical Laboratory Foundation （The fourth edition）. The present fibrinogen reference interval was established through longitudinal study in our laboratory. Consistency checking was applied for the comparison of these reference intervals and decided by the Kappa value. Results The previous Fg reference interval was 2. 00-4. 00 g/L. The present Fg reference intervals of the first, secong, third trimester and postpartum were 2. 73-4. 93, 2. 94-5.00, 3.01-5. 98, 1.76-3.60 g/L respectively. Compared to the previous Fg interval, after using present Fg reference interval the abnormal rate was reduced into 1/4. Through the consistency test, we figured out that Kappa = 0. 128 （ 〈 0. 4）, U = 26. 825, P 〈 0. 05 and these two intervals were inconsistent in criteria judging. Then we took further analysis for inconsistent data. Totally 6 270 cases were judged normal by the present interval but abnormal by the previous one, accounting for 50. 47%. The present Fg reference intervals reduced the abnormal judgment markedly, which was induced by physiological Fg increase. And thus it cut down the misdiagnosis rate; 323 cases were judged abnormal by the previous interval but normal by the present one, accounting for 2. 6%. Furthermore, there were 303 cases lower than the present interval, showing the present Fg reference intervals increased the sensitivity to abnormal low fibrinogen results and reduced the rate of missed diagnosis. Conclusion From an economic point of view, the present fibrinogen reference intervals are more applicable and economic while considering the practicality; the present fibrinogen reference intervals are more sensitive in evaluating the dangers for pregnancy.