Department of Dermatology and Venereology, First Affiliated Hospital of Kunming Medical University, Kunming, 650032, China.
School of Public Health, Kunming Medical University, Kunming, 650500, China.
Eur J Med Res. 2019 Feb 2;24(1):7. doi: 10.1186/s40001-019-0367-8.
Early diagnosis of congenital syphilis (CS) is difficult. This study aimed to determine the serological response discipline of syphilis passive antibody (SPA) in infants born to mothers with syphilis and provide the basis for the early diagnosis of CS.
Thirty-three infants born to mothers with syphilis and six infants with CS were recruited. The toluidine red unheated serum test (TRUST) and Treponema pallidum particle agglutination (TPPA) titers were followed up after birth.
The results showed that serological response in the serum of infants with the TPPA titer decreased threefold at 3rd month, or the titer dropped to a minimum of 1:40 at 9th month was SPA. The TPPA titer of 6 CS cases remained positive after 3-year follow-up, and the titer did not decline after treatment and maintained longer. The infants with TRUST titer ≥ 1:4 at birth were prone to become syphilis serofast, while TRUST titer < 1:4 turned to negative quickly.
In infants with SPA, the TRUST converted negative earlier than the TPPA. The lower the TPPA initial titer was, the shorter the seroreversion time required. The TPPA titer can be used to predict CS in infants born to mothers with syphilis.
先天性梅毒（CS）的早期诊断较为困难。本研究旨在明确梅毒螺旋体被动抗体（SPA）在梅毒母亲所生婴儿中的血清学反应规律，为 CS 的早期诊断提供依据。
选择 33 例梅毒母亲所生婴儿及 6 例 CS 婴儿，进行出生后随访甲苯胺红不加热血清试验（TRUST）及梅毒螺旋体明胶颗粒凝集试验（TPPA）滴度。
结果显示，TPPA 滴度在 3 月龄下降 3 倍，或 9 月龄时滴度降至 1∶40 及以下者为 SPA；6 例 CS 患儿 TPPA 随访 3 年均为阳性，治疗后滴度不降，维持时间更长；出生时 TRUST 滴度≥1∶4 者易发生梅毒血清固定，TRUST 滴度＜1∶4 者转归迅速。
SPA 婴儿中 TRUST 转阴早于 TPPA，TPPA 初始滴度越低，血清阴转时间越短，TPPA 滴度可用于预测梅毒母亲所生婴儿 CS 的发生。
