Dai Lin, Huang Juan, Tang Yuan, Liao Dian-ying, Dong Dan-dan, Xu Gang, Li Gan-di
Department of Pathology, West China Hospital of Sichuan University, Chengdu 610041, China.
Zhonghua Bing Li Xue Za Zhi. 2010 Jun;39(6):361-5.
To study the roles of histologic examination and polymerase chain reaction in diagnosis of toxoplasmic lymphadenitis (TL).
Forty-six archival cases of histologically diagnosed TL, encountered during the period from April, 1999 to September, 2009 and with the paraffin-embedded lymph node tissue blocks available, were enrolled into the study. The presence of genome fragments of Toxoplasma gondii (T. gondii) was analyzed using semi-nested polymerase chain reaction (PCR). Thirty cases of one or two histopathologic triad of TL as the controls.
The positive rate of PCR in TL group was 76.1% (35/46), as compared to 10.0% (3/30) in the control group. The difference was of statistical significance. The sensitivity and specificity of the histologic triad in diagnosing TL was 92.1% (35/38) and 71.1% (27/38), respectively. The predictive value of positive and negative PCR results was 76.1% (35/46) and 90.0% (27/30). respectively.
The high specificity but low sensitivity of applying the histologic triad in diagnosing TL cases may be due to the occurrence of atypical histologic pattern. The sensitivity is improved with the use of semi-nested PCR in detecting T. gondii DNA.
研究组织学检查和聚合酶链反应在弓形虫性淋巴结炎（TL）诊断中的作用。
纳入1999年4月至2009年9月期间组织学诊断为TL的46例存档病例，这些病例有石蜡包埋的淋巴结组织块。采用半巢式聚合酶链反应（PCR）分析弓形虫基因组片段的存在情况。以30例具有TL一个或两个组织病理学三联征的病例作为对照。
TL组PCR阳性率为76.1%（35/46），对照组为10.0%（3/30）。差异具有统计学意义。组织学三联征诊断TL的敏感性和特异性分别为92.1%（35/38）和71.1%（27/38）。PCR阳性和阴性结果的预测值分别为76.1%（35/46）和90.0%（27/30）。
应用组织学三联征诊断TL病例特异性高但敏感性低，可能是由于非典型组织学模式的出现。使用半巢式PCR检测弓形虫DNA可提高敏感性。
