妊娠合并梅毒孕期规范治疗后新生儿梅毒血清学的变化特点及转归

Serological changes for syphilis in infants born to treated syphilitic mothers

目的 了解妊娠合并梅毒孕母所生新生儿梅毒血清学变化特点,初步探讨影响婴儿梅毒血清学转归的因素.方法 选择我院2006年1月至2008年1月经孕期规范治疗后的146例单胎妊娠合并梅毒的孕妇,孕妇产前和新生儿生后3 d内行快速血浆反应素试验（rapid plasma reagin,RPR）及梅毒螺旋体明胶凝集试验（treponema pallidum particle agglutination assay,TPPA）.随访了其中92例婴儿生后24个月内RPR及TPPA的情况.结果 （1）146例新生儿中,140例（95.9%）TPPA阳性,其中94例（90.4%）新生儿期RPR滴度低于或等同于母亲产前RPR滴度;104例（71.2%）RPR和TPPA均为阳性,36例（24.7%）新生儿为TPPA单阳性.RPR和TPPA双阳性母亲的新生儿RPR阳性比例明显高于TPPA单阳性母亲新生儿（81.4%和36.4%,χ2=25.3,P〈0.01）.（2）随访的92例婴儿中,出生时RPR及TPPA双阳性者57例,56例（98.2%）的RPR在生后6个月内转阴,8个月内100%转阴,转阴高峰为生后2个月（78.9%,45例）;TPPA在生后24个月内100%转阴.转阴高峰为生后10～18个月（64.9%,37例）.TPPA单阳性的35例婴儿中,18个月内TPPA 100%转阴,转阴高峰在生后6～12个月（57.1%,20例）.（3）母亲产前RPR滴度为1：1～1：4时,其婴儿RPR转阴时间晚于母亲RPR阴性者（P〈0.05）,1;4组为（2.5±0.8）月,长于1：1组的（1.2±0.4）月（P〈0.01）;但母亲产前RPR滴度与婴儿生后TPPA转阴时间无关（P〉0.05）.新生儿期的RPR滴度为1：4时,婴儿RPR转阴所需时间晚于1：1的新生儿[（3.7±0.9）月和（2.3±0.6）月,P〈0.01];RPR滴度为1：1～1：4的新生儿,婴儿期TPPA转阴所需时间均晚于RPR阴性组[（11.0±2.2）月、（12.2±2.9）月、（11.2±2.8）月和（6.9±2.1）月,P〈0.01）].结论 妊娠合并梅毒孕妇孕期规范治疗后分娩的新生儿梅毒血清学检测大部分仍呈阳性,母亲产前或分娩时静脉血RPR滴度高的婴儿,其阳性持续时间可能较长,但均能在生后一定时间内转阴.建议对梅毒血清学阳性新生儿生后长期随访,诊断先天性梅毒应慎重.

Objective To explore the serological variations for syphilis in infants delivered by treated syphilitic mothers and its influencing factors. Methods Totally, 146 singleton gravidas, who had been treated for syphilis during pregrancy from January 2006 to January 2008 in our hospital, were chosen. Rapid plasma reagin（RPR） and treponema pallidum particle agglutination assay （TPPA） of these mothers before delivery and of the newborns within 3 d after delivery were tested and 92 of the 146 babies were followed up until the age of 24 months. Results （1） Among the 146 neonates, 104 （71.2%） were positive for both RPR and TPPA and 140 （95.9%） TPPA positive only. The RPR positive rate in neonates born to RPR＋ ＋ TPPA＋ mothers were higher than those born to TPPA＋ （only） mothers （81.4% vs 36.4%,χ2 = 25. 3, P〈0. 01）. 90.4% of the RPR＋ neonates （94/104） showed lower or equivalent RPR titers compared to their mothers. （2） Among the 92 babies bein g followed up, the seroreversion of RPR were found in 98. 2%（n = 56） of the 57 babies, who were RPR＋ ＋TPPA＋ at delivery, at the 6 months and 100% （n=57） within 8 months, with the peak time within 2 months after birth （78. 9%, n = 45）. While, 100% of the babies were found to be TPPA-within 24 mo with the peak time at 10～18 mo （64. 9%, n = 37）. For those babies with TPPA＋ at delivery, all turned to be TPPA- at 18 mo, with the peak time at 6 ～ 12 mo （57. 1%, n = 20）. （3） The seroreversion time of babies with maternal RPR between 1：1～1：4 was later than those with maternal RPR （P〈0.05）. The seroreversion time of babies with maternal RPR titer of 1：4 was longer than those with maternal RPR titer of 1 〉 1 [（2.5±0.8） mo vs （1. 2±0. 4） mo,P〈0. 01]. However, the maternal RPR titer did not affect the TPPA reversion time （P 〉 0.05）. The seroreversion time of RPR in infants with neonatal RPR titer of 1 ： 4 was later than those with neonatal RPR titer of 1：1 [（3.7±0. 9） mo vs （2. 3±0. 6） mo,P〈0. 01], and babies with RPR titer at 1 ： 1 - 1 ：4 showed longer duration than those with neonatal RPR- in TPPA seroreversion [（11. 2±2. 8） mo, （12.2±2.9） mo, and （11.0±2.2） mo vs （ 6. 9±2. 1） mo, P〈 0.01, respectively]. Conclusions Most infants born to syphilitic mothers are serological positive for syphilis despite of standard maternal treatment during pregnancy. Infants, with higher maternal RPR titer during the pregnancy or at delivery, may persist to be serological positive for syphilis for a longer perieod, but all will turn to negative finally. Long term follow up is recommended for serological positive infants, and the diagnosis of congenital syphilis should be cautious.