Universidade Federal da Grande Dourados, Laboratório de Pesquisa em Ciências da Saúde, Dourados, Mato Grosso do Sul, Brazil.
Universidade Federal da Bahia, Instituto de Ciências da Saúde, Laboratório de Imunologia e Biologia Molecular, Salvador, Bahia, Brazil.
Rev Inst Med Trop Sao Paulo. 2022 Nov 14;64:e75. doi: 10.1590/S1678-9946202264075. eCollection 2022.
Syphilis is caused by the bacterium Treponema pallidum. The diagnosis is based on clinical data and serological analysis; however, the sensitivity and specificity of such tests may vary depending on the type of test and stage of the infection. In order to overcome this premise, this study utilized the polymerase chain reaction (PCR) for the detection of T. pallidum DNA in whole blood samples of patients with syphilis. The blood samples from patients with or without symptoms of syphilis, but with positive results in enzyme-linked immunosorbent assay (ELISA), were included in this study. A venereal disease research laboratory (VDRL) test was performed for all collected sera samples. For PCR, the T. pallidum DNA was extracted from the collected blood samples and a specific primer set was designed to amplify 131 nucleotides of polA (Tp0105). The specificity of the primers was evaluated with the DNA of 17 different pathogens. From a total of 314 blood samples reactive in ELISA, 58.2% (183/314) of the samples were reactive in the VDRL test. In the PCR, 54% (168/314) of the ELISA-reactive samples were positive. In both tests (VDRL and PCR) 104 samples were positive. Of 104 positive samples for both tests, 71 were at the latent stage. Based on these results, it can be concluded that PCR with the designed set of primers can be utilized as a diagnostic method for T. pallidum detection in blood samples of patients with syphilis, especially those with latent infection. In addition, it can be utilized as a supplement for serological methods to improve the diagnosis of syphilis.
梅毒是由苍白密螺旋体引起的。诊断基于临床数据和血清学分析；然而，这些测试的敏感性和特异性可能因测试类型和感染阶段而异。为了克服这一前提，本研究利用聚合酶链反应（PCR）检测梅毒螺旋体 DNA 在梅毒患者的全血样本中。本研究纳入了有或无症状但酶联免疫吸附试验（ELISA）阳性的梅毒患者的血液样本。对所有采集的血清样本均进行性病研究实验室（VDRL）检测。对于 PCR，从采集的血液样本中提取 T. pallidum DNA，并设计了一套特异性引物来扩增 polA（Tp0105）的 131 个核苷酸。用 17 种不同病原体的 DNA 评估引物的特异性。在总共 314 个在 ELISA 中反应的血液样本中，58.2%（183/314）的样本在 VDRL 测试中反应。在 PCR 中，54%（168/314）的 ELISA 反应样本为阳性。在这两项测试（VDRL 和 PCR）中，共有 104 个样本呈阳性。在这两项测试均为阳性的 104 个样本中，71 个处于潜伏阶段。根据这些结果，可以得出结论，设计的引物 PCR 可用于检测梅毒患者血液样本中的 T. pallidum，特别是潜伏感染的患者。此外，它可以作为血清学方法的补充，以提高梅毒的诊断。
