羊水寄生虫载量水平与先天性弓形虫病临床结局的关联

Association of Parasite Load Levels in Amniotic Fluid With Clinical Outcome in Congenital Toxoplasmosis.

作者信息

Yamamoto Lidia, Targa Lília S, Sumita Laura M, Shimokawa Paulo T, Rodrigues Jonatas C, Kanunfre Kelly A, Okay Thelma S

机构信息

Laboratory of Seroepidemiology and Immunobiology and Laboratory of Virology, Institute of Tropical Medicine, and LIM 48-Laboratory of Immunology, Department of Infectious and Parasitic Diseases, School of Medicine, University of São Paulo, São Paulo, Brazil.

出版信息

Obstet Gynecol. 2017 Aug;130(2):335-345. doi: 10.1097/AOG.0000000000002131.

DOI:10.1097/AOG.0000000000002131

PMID:28697120

Abstract

OBJECTIVE

To correlate neonatal and infant clinical outcome with parasite load in amniotic fluid (AF).

METHODS

We conducted a retrospective cohort study of 122 children whose mothers had toxoplasmosis during pregnancy. The children were monitored from birth to 12 months old. Stored AF samples were obtained at maternal diagnosis and tested by quantitative polymerase chain reaction. Gestational age at maternal infection, quantitative polymerase chain reaction results, neonatal anti-Toxoplasma gondii immunoglobulin (Ig) M, and clinical outcome at 12 months were correlated.

RESULTS

Maternal infection occurred in 18 of 122 (14.7%) and 104 of 122 (85.2%) women in the first and second trimesters, respectively. At birth, IgM was present in 107 of 122 (87.7%) neonates and 36 (29.5%) were symptomatic. Of these, half occurred in the first and the other half in the second trimester and 6 of 36 had severe infections (16.7% of symptomatic, 4.9% of total), all infected in the first trimester. Parasite load levels were highly variable (median 35 parasites/mL, range 2-30,473). Logistic regression correlated symptomatic infection with gestational age (odds ratio [OR] 0.47, CI 0.31-0.73) and parasite load (OR 2.04, CI 1.23-3.37), but not with positive IgM (OR 6.81, CI 0.86-53.9). Negative correlations were found between gestational age and parasite load (rs -0.780, CI -0.843 to -0.696), gestational age and symptoms (rs -0.664, CI -0.755 to -0.547), but not gestational age and IgM (rs -0.136, CI -0.311 to 0.048). Parasite load levels distributed by percentile showed that all symptomatic patients appeared from the 75th percentile and all severe infections from the 95th percentile. Load rankings showed doubled the OR for each 20 parasite/mL increment. Parasite load was associated with symptomatic infections (area under the curve 0.959, CI 0.908-0.987) as well as gestational age (area under the curve 0.918, CI 0.855-0.960) and both parameters combined (area under the curve 0.969, CI 0.920-0.992).

CONCLUSION

Parasite load in AF is associated with the clinical outcome in congenital toxoplasmosis, irrespective of gestational age at maternal infection.

摘要

目的

将新生儿及婴儿的临床结局与羊水（AF）中的寄生虫载量进行关联分析。

方法

我们对122名母亲在孕期患有弓形虫病的儿童进行了一项回顾性队列研究。对这些儿童从出生至12个月进行监测。在母亲确诊时获取储存的羊水样本，并通过定量聚合酶链反应进行检测。将母亲感染时的孕周、定量聚合酶链反应结果、新生儿抗弓形虫免疫球蛋白（Ig）M以及12个月时的临床结局进行关联分析。

结果

122名女性中，分别有18名（14.7%）和104名（85.2%）在孕早期和孕中期感染。出生时，122名新生儿中有107名（87.7%）IgM呈阳性，36名（29.5%）有症状。其中，一半发生在孕早期，另一半发生在孕中期，36名中有6名有严重感染（占有症状者的16.7%，占总数的4.9%），均在孕早期感染。寄生虫载量水平差异很大（中位数为35个寄生虫/毫升，范围为2 - 30473）。逻辑回归分析显示，有症状感染与孕周（比值比[OR] 0.47，可信区间[CI] 0.31 - 0.73）和寄生虫载量（OR 2.04，CI 1.23 - 3.37）相关，但与IgM阳性无关（OR 6.81，CI 0.86 - 53.9）。发现孕周与寄生虫载量之间呈负相关（rs -0.780，CI -0.843至 -0.696），孕周与症状之间呈负相关（rs -0.664，CI -0.755至 -0.547），但孕周与IgM之间无负相关（rs -0.136，CI -0.311至0.048）。按百分位数分布的寄生虫载量水平显示，所有有症状的患者均出现在第75百分位数以上，所有严重感染均出现在第95百分位数以上。载量排名显示，每增加20个寄生虫/毫升，OR值翻倍。寄生虫载量与有症状感染相关（曲线下面积0.959，CI 0.908 - 0.987），与孕周也相关（曲线下面积0.918，CI 0.855 - 0.960），两者联合时相关（曲线下面积0.969，CI 0.920 - 0.992）。