van der Ryst E, Smith M S, Visagie H M
Department of Virology, University of the Orange Free State, Bloemfontein, South Africa.
J Infect. 1996 Mar;32(2):109-12. doi: 10.1016/s0163-4453(96)91219-0.
Human T-lymphotropic virus type I (HTLV-I) is associated with tropical spastic paraparesis (TSP) and adult T-cell leukaemia/ lymphoma (ATL). HTLV-I seroconversion may not take place for many years after infection and some patients develop relatively low concentrations of antibodies that are difficult to detect by means of conventional assays. Some serologic tests also yield high rates of false-positive results. We therefore decided to determine whether the polymerase chain reaction (PCR) might be more sensitive than serology for the diagnosis of HTLV-I infection. Samples of serum and of peripheral blood mononuclear cells were obtained from 50 patients with spastic myelopathy and nine with T-cell neoplasia. The serum samples of serum were tested for the presence of HTLV-I antibodies by means of an enzyme-linked immunosorbent assay (ELISA). Positive results were confirmed by Western blot (WB) assay. DNA was extracted from the peripheral blood mononuclear cells and a PCR performed by use of two primer pairs from the env and pol regions of the proviral genome. Seven of the 50 patients with myelopathy and none of those with T-cell neoplasia had detectable antibodies to HTLV-I and all seven were PCR positive. One patient with an indeterminate WB result and one who was HTLV-I antibody-negative, both with myelopathy, were also PCR-positive. In this study, PCR was found to be more sensitive than serology for the diagnosis of HTLV-I infection. PCR should therefore be considered for selected HTLV-I antibody-negative patients with unexplained spastic myelopathy or T-cell neoplasia.
人类嗜T淋巴细胞病毒I型（HTLV-I）与热带痉挛性截瘫（TSP）以及成人T细胞白血病/淋巴瘤（ATL）相关。感染后多年可能不会发生HTLV-I血清转化，一些患者产生的抗体浓度相对较低，难以通过传统检测方法检测到。一些血清学检测还会产生较高的假阳性率。因此，我们决定确定聚合酶链反应（PCR）在诊断HTLV-I感染方面是否比血清学更敏感。从50例痉挛性脊髓病患者和9例T细胞肿瘤患者中获取血清和外周血单个核细胞样本。通过酶联免疫吸附测定（ELISA）检测血清样本中HTLV-I抗体的存在。阳性结果通过蛋白质印迹（WB）测定进行确认。从外周血单个核细胞中提取DNA，并使用来自前病毒基因组env和pol区域的两对引物进行PCR。50例脊髓病患者中有7例可检测到HTLV-I抗体，而T细胞肿瘤患者中无一例可检测到，且所有7例PCR均为阳性。1例WB结果不确定的患者和1例HTLV-I抗体阴性的患者，均患有脊髓病，PCR也呈阳性。在本研究中，发现PCR在诊断HTLV-I感染方面比血清学更敏感。因此，对于选定的HTLV-I抗体阴性且患有不明原因痉挛性脊髓病或T细胞肿瘤的患者，应考虑进行PCR检测。
