Fonseca Zulmirene Cardoso, Rodrigues Isolina Maria Xavier, Melo Natália Cruz E, Avelar Juliana Boaventura, Castro Ana Maria, Avelino Mariza Martins
Department of Gynecology and Obstetrics, Faculty of Medicine, Federal University of Goias (UFG), Goiania GO 74045-155, Brazil.
Laboratory of Immunology of Clinical Hospital of UFG, Goiania GO 74605-020, Brazil.
Pathogens. 2017 Jun 18;6(2):26. doi: 10.3390/pathogens6020026.
The goal of this study was to investigate the importance of IgG avidity testing in newborns (NBs) diagnosed with early congenital toxoplasmosis. We collected samples from 88 puerperae infected by Toxoplasma gondii (T. gondii) and their NBs (48 acutely-infected puerperae (AIP) and 40 chronically-infected puerperae (CIP)), from two public maternity hospitals in Goiania city, Goias, Brazil, from 2010 to 2015. Specific anti-T. gondii IgM and IgG serum levels and IgG avidity tests were evaluated using chemiluminescence. Congenital toxoplasmosis was observed in 66.66% (n = 32) of NBs with AIP, 94.1% presenting low avidity (LA) and 51.61% presenting high avidity (HA) test results. The IgG and IgM levels of NBs with LA and their puerperae were higher in comparison with HA NBs and puerperae (p = 0.0001). The avidity tests showed 100% specificity and 50% sensitivity (p = 0.0001). NBs with LA had a 15-fold increased risk of developing congenital toxoplasmosis in comparison with HA NBs. The IgG avidity test could be used to assist in early congenital toxoplasmosis diagnoses in NBs and LA, identifying a greater probability of vertical transmission.
本研究的目的是调查IgG亲和力检测在诊断为早期先天性弓形虫病的新生儿中的重要性。我们从巴西戈亚斯州戈亚尼亚市的两家公立妇产医院收集了88例感染弓形虫的产妇及其新生儿的样本（48例急性感染产妇（AIP）和40例慢性感染产妇（CIP）），时间跨度为2010年至2015年。使用化学发光法评估特异性抗弓形虫IgM和IgG血清水平以及IgG亲和力检测。在AIP的新生儿中，66.66%（n = 32）观察到先天性弓形虫病，94.1%呈现低亲和力（LA），51.61%呈现高亲和力（HA）检测结果。与HA新生儿及其产妇相比，LA新生儿及其产妇的IgG和IgM水平更高（p = 0.0001）。亲和力检测显示特异性为100%，敏感性为50%（p = 0.0001）。与HA新生儿相比，LA新生儿患先天性弓形虫病的风险增加了15倍。IgG亲和力检测可用于辅助诊断新生儿和LA中的早期先天性弓形虫病，确定垂直传播的可能性更大。
