Espino A M, Díaz A, Pérez A, Finlay C M
Departamento de Parasitología, Instituto de Medicina Tropical "Pedro Kouri" (IPK), Ciudad de La Habana, Cuba.
J Clin Microbiol. 1998 Sep;36(9):2723-6. doi: 10.1128/JCM.36.9.2723-2726.1998.
In the present study the dynamics of antigenemia and coproantigens were studied in patients with Fasciola hepatica infection during an outbreak occurring in La Palma, Pinar del Río, in the West Province of Cuba. Stool and serum samples were collected from 67 patients and 40 healthy subjects. Stool samples were studied by a simple gravity sedimentation technique and an ES78 sandwich enzyme-linked immunosorbent assay (ELISA) for observation of eggs and detection of parasite coproantigens, respectively. Serum samples were also studied by the ES78 sandwich ELISA and an indirect ELISA to detect circulating antigens and antibodies, respectively. At the beginning of the study, 8 of 67 patients had patent infections and 59 had prepatent infections, which was determined by the recent consumption of lettuce contaminated with metacercariae of F. hepatica, the presence of clinical symptoms, and the absence of Fasciola eggs in their stools. Patients with prepatent infections were monitored by all techniques until patency. Circulating antigens were not detected in patients with patent infections. However, coproantigens were clearly detected in all patients with patent infections. On the other hand, 28.8% of patients with prepatent infections tested positive for circulating antigens and 81.4% tested positive for coproantigens in the first stool sample studied. Only two other coproantigen determinations were necessary to diagnose 93.2% of the patients. While circulating antigen levels diminished in all patients during the infection, coproantigen levels increased. The present study demonstrates that the ES78 sandwich ELISA is a better tool than parasitological examination for diagnosis of active early infection, since by the combination of the circulating-antigen detection assay and the coproantigen detection assay 91% of patients were able to be diagnosed at the beginning of the study. In contrast, a coprologic analysis repeated over several weeks was necessary to diagnose 100% of the patients.
在本研究中，对古巴西部比那尔德里奥省帕尔马岛发生的一次肝片吸虫感染疫情期间的肝片吸虫病患者的抗原血症和粪抗原动态进行了研究。从67例患者和40名健康受试者中采集了粪便和血清样本。粪便样本分别采用简单的重力沉降技术和ES78夹心酶联免疫吸附测定法（ELISA）进行研究，以观察虫卵和检测寄生虫粪抗原。血清样本也分别采用ES78夹心ELISA和间接ELISA进行研究，以检测循环抗原和抗体。在研究开始时，67例患者中有8例为显性感染，59例为隐性感染，这是通过近期食用受肝片吸虫囊蚴污染的生菜、临床症状的存在以及粪便中无肝片吸虫卵来确定的。对隐性感染患者采用所有技术进行监测，直至出现显性感染。在显性感染患者中未检测到循环抗原。然而，在所有显性感染患者中均清晰检测到粪抗原。另一方面，在首次研究的粪便样本中，28.8%的隐性感染患者循环抗原检测呈阳性，81.4%的患者粪抗原检测呈阳性。仅需另外两次粪抗原测定就能诊断93.2%的患者。在感染期间，所有患者的循环抗原水平均下降，而粪抗原水平升高。本研究表明，ES78夹心ELISA比寄生虫学检查是诊断早期活动性感染的更好工具，因为通过循环抗原检测法和粪抗原检测法相结合，在研究开始时91%的患者能够被诊断出来。相比之下，需要在数周内反复进行粪便学分析才能诊断100%的患者。
