Paula Fabiana Martins de, Malta Fernanda Mello, Corral Marcelo Andreetta, Marques Priscilla Duarte, Gottardi Maiara, Meisel Dirce Mary Correia Lima, Yamashiro Juliana, Pinho João Renato Rebello, Castilho Vera Lucia Pagliusi, Gonçalves Elenice Messias do Nascimento, Gryschek Ronaldo César Borges, Chieffi Pedro Paulo
Universidade de São Paulo, Instituto de Medicina Tropical de São Paulo. São Paulo, SP, Brazil. E-mails:
Universidade de São Paulo, Hospital das Clínicas da Faculdade de Medicina, Laboratório de Investigação Médica. São Paulo, SP, Brazil. E-mails:
Rev Inst Med Trop Sao Paulo. 2016 Sep 22;58:63. doi: 10.1590/S1678-9946201658063.
Strongyloidiasis is a potentially serious infection in immunocompromised patients. Thus, the availability of sensitive and specific diagnostic methods is desirable, especially in the context of immunosuppressed patients in whom the diagnosis and treatment of strongyloidiasis is of utmost importance. In this study, serological and molecular tools were used to diagnose Strongyloides stercoralis infections in immunosuppressed patients. Serum and stool samples were obtained from 52 patients. Stool samples were first analyzed by Lutz, Rugai, and Agar plate culture methods, and then by a quantitative real time polymerase chain reaction (qPCR). Serum samples were evaluated by an enzyme-linked immunosorbent assay (ELISA) using a soluble (AS) or a membrane fractions antigen (AM) obtained from alkaline solutions of the filariform larvae of Strongyloides venezuelensis. Of the 52 immunosuppressed patients, three (5.8%) were positive for S. stercoralis by parasitological methods, compared to two patients (3.8%) and one patient (1.9%) who were detected by ELISA using the AS and the AM antigens, respectively. S. stercoralis DNA was amplified in seven (13.5%) stool samples by qPCR. These results suggest the utility of qPCR as an alternative diagnostic tool for the diagnosis of S. stercoralis infection in immunocompromised patients, considering the possible severity of this helminthiasis in this group of patients.
类圆线虫病在免疫功能低下的患者中是一种潜在的严重感染。因此，需要有灵敏且特异的诊断方法，特别是对于免疫抑制患者而言，类圆线虫病的诊断和治疗至关重要。在本研究中，采用血清学和分子工具来诊断免疫抑制患者中的粪类圆线虫感染。从52名患者处获取血清和粪便样本。粪便样本首先通过卢茨法、鲁盖法和琼脂平板培养法进行分析，然后采用定量实时聚合酶链反应（qPCR）进行检测。血清样本通过酶联免疫吸附测定（ELISA）进行评估，该方法使用从委内瑞拉类圆线虫丝状蚴的碱性溶液中获得的可溶性抗原（AS）或膜组分抗原（AM）。在这52名免疫抑制患者中，通过寄生虫学方法检测出3例（5.8%）粪类圆线虫阳性，相比之下，分别使用AS抗原和AM抗原通过ELISA检测出的患者为2例（3.8%）和1例（1.9%）。通过qPCR在7份（13.5%）粪便样本中扩增出粪类圆线虫DNA。考虑到该蠕虫病在这组患者中可能的严重性，这些结果表明qPCR作为诊断免疫抑制患者粪类圆线虫感染的一种替代诊断工具具有实用性。
