免疫组织化学检测梅毒螺旋体及其临床意义

Immunohistochemistry detection of Treponema pallidum and its clinical significance

目的探讨免疫组织化学法检测梅毒螺旋体（TP）对常规诊断手段不能确诊的梅毒的诊断意义。方法采用兔抗人TP多克隆抗体标记的免疫组织化学法检测浙江大学附属邵逸夫医院2004年1月至2012年5月就诊的14例20份梅毒血清阳性患者或窗口期疑似患者的活组织检查石蜡包埋标本。结果免疫组织化学法检测病变组织中TP的总阳性数为16份，其中梅毒1期5／6、2期10／10、3期1／4，阳性、阴性诊断符合率均为100．0％。TP在组织中的分布以亲表皮、亲血管内皮细胞和亲炎性肉芽组织为特点。TP数量与病变类型有一定相关性：硬下疳、扁平湿疣、梅毒性直肠炎组织中TP数量最多；鳞屑性红斑、蛎壳样斑块、3期梅毒胸壁溃疡中次之；梅毒性淋巴结炎组织中TP数量最少。TP表达阳性程度与快速血浆反应素试验（RPR）效价无关（P〉0．05）。结论用兔抗人TP多克隆抗体标记的免疫组织化学法检测TP的敏感性和特异性均很高，对于临床难确诊病例如血清学试验阴性的早期梅毒、梅毒系统性损害或少见且不典型梅毒病变，不失为一种可选择的确诊手段。

Objective To evaluate the diagnostic value of immunohistochemistry （IHC） for the identification and localization of Treponema pallidum （TP）. Methods Rabbit anti-human TP polyclonal antibody labeled IHC was used to detect 20 paraffin-embedded biopsy samples from lesions of 14 patients with syphilis or suspected syphilis in Sir Run Run Shaw Hospital of Zhejiang University from January 2004 to May 2012. Results TP was detected in 80% of all the 20 samples by IHC assay, including 83. 3% （5/6） in patients with primary syphilis, 100. 0% （10/10） in patients with secondary syphilis, and 25. 0% （1/4） in patients with tertiary syphilis, with a positive diagnostic accuracy of 100.0%. TP was mainly present in lower part of epidermis or perivascular, characterized by an endotheliotropic and epitheliotropic patterns or in the tissue of granulomatous inflammation. Besides, the density of TP was associated with types of lesions. There were more TP in the lesions of syphilis chancre, syphilis proctitis and condyloma latum, and fewer TP in the lesions of squamous erythema, greyish-black plaque, ulcer of chest wall from tertiary syphilis, and least in syphilitic lymphadenitis. There were no correlations between the quantity of TP and the rapid plasma regain （RPR） test titer （P〉0.05）. Conclusions IHC for TP is of both high sensitivity and specificity for the diagnosis of syphilis, suggesting that TP-IHC is helpful for the diagnosis of syphilis, especially forthe diagnosis of early suspected syphilis with negative serological results, systemic damage of syphilis, or syphilis in untypical locations and unusual lesions. It can serve as an alternative method for the diagnosis of syphilis.