A laboratory and clinical study of the mechanism of mother-to-child infection of Toxoplasma

ObjectivesCongenital Toxoplasma感染在新生儿疾病中经常出现的结果。为了更好地评估母体感染的周期，我们测试了母体抗毒素抗体IgG的avidity。研究方法1 100和44个抗毒素抗体IgM阳性妊娠妇女对IgG的avidity进行了前瞻性测试，以确定毒素抗体感染的周期。We adapted this serologic technique to a commercial ELISA kit "Toxo IgG EIA Seiken" （Denka Seiken， Japan） using 8 M urea as a dissociating agent。Results·The mean specific IgM of the pregnant women was 2.65 +/-1.36。·在144名怀孕妇女中，有123名（85.4%）有高置信度结果（先前感染的指标）， 9名（6.3%）有低置信度结果（最近感染的指标），12名（8.3%）有低置信度结果。所有72个新生儿都没有生理和神经异常。三个是LFD，八个是HFD，55个是AFD。Neonates ; 72种无异常情况·阳性反毒素等离子体IgM ; 0/66·抗毒素等离子体IgM ： 0.24±0.12 （m±SD）·安慰剂的非正常病理发现： 0/29·安慰剂和脐带血中的阳性PCR： 0/16·不正常基础分析发现： 0/36·非正常CT扫描发现： 0/29·抗毒素等离子体IgG的半衰期：31.4±4.5天（23个非感染性流产）作为一种高IgG易感性可以区分以前受IgM阳性怀孕妇女影响的妇女，对易感性的衡量将防止不必要的免疫力、医学和人工流产。

ObjectivesCongenital Toxoplasma infection in the fetus frequently results in debilitating disease in the newborn. To better evaluate the period of maternal infection, we examined avidity of maternal anti-Toxoplasma IgG.Study MethodsOne hundred and forty-four anti-Toxoplasma IgM-positive pregnant women were prospectively tested for IgG avidity for Toxoplasma to determine the period of Toxoplasma infection. We adapted this serologic technique to a commercial ELISA kit "Toxo IgG EIA Seiken" (Denka Seiken, Japan) using 8 M urea as a dissociating agent.Results・The mean specific IgM of the pregnant women was 2.65 +/-1.36.・Of the 144 pregnant women 123 (85.4%) had high avidity results (indicative of previous infection), 9(6.3%) had low avidity results (indicative of recent infection), and 12 (8.3%) had borderline results.・All of 72 neonates had no physical and neurological abnormality. Three were LFD, 8 were HFD, and 55 were AFD.・neonates ; 72 cases without anomaly・positive anti-Toxoplasma IgM ; 0/66・anti-Toxoplasma IgM : 0.24±0.12 (m±SD)・abnormal pathological findings of placenta : 0/29・positive PCR in placenta and cord bloods : 0/16・Abnormal funduscopic findings : 0/36・Abnormal CT scan findings : 0/29・Half-life of anti-Toxoplasma IgG : 31.4±4.5 days (23 non-infected offspring)ConclusionsAs a high IgG avidity can differentiate previously inflected women from IgM-positive pregnant women, measurement of the avidity will avoid unnecessary amniocentesis, medication, and artificial abortion.