Dot enzyme-linked immunosorbent assay (dot-ELISA) for schistosomiasis diagnosis using dacron as solid-phase.

Dacron and nitrocellulose were evaluated as matrices for the dot enzyme linked immunosorbent assay (dot-ELISA) for schistosomiasis and compared to indirect immunofluorescence (IMF). Titration of sera from 18 schistosomiasis patients against soluble worm antigen preparation (SWAP) was carried out and sera from healthy individuals from non-endemic areas were used as controls. The IMF was less sensitive than the dot-ELISAs, although the difference was not statistically significant (p > 0.05). The dot-ELISA based on nitrocellulose was as sensitive as that using dacron. Stability did not differ between nitrocellulose and dacron. Specificity was lower when dacron was used than when nitrocellulose was used, although the difference was not statistically significant (p > 0.05). In conclusion, this work showed that nitrocellulose and dacron performed similarly in dot-ELISA, suggesting that they may be used alternatively in population surveillance in endemic areas.

Neurocysticercosis in persons with epilepsy in Medellín, Colombia. The Neuroepidemiological Research Group of Antioquia.

PURPOSE: A prospective series of 643 persons with epilepsy attending a reference neurologic center in Medellín, Colombia, was examined by computed tomography (CT scan) or serology or both with the enzyme-linked immunoelectrotransfer blot assay (EITB) to assess the prevalence of Taenia solium cysticercosis. METHODS: All presenting patients were consecutively enrolled in the study. Five hundred forty-six persons underwent cerebral CT scans; 376 of them also had serum EITB performed. RESULTS: Prevalence of neurocysticercosis by CT scan was 13.92%. Overall prevalence of T. solium antibodies with EITB was 9.82%, but for those with late-onset epilepsy (onset after age 30 years), prevalence increased to 17.5% and 19% for those who originated from outside urban Medellín. Seroprevalence in individuals with mixed lesions (cysts and calcifications) was 88.2% and 64.10% in those with live cysts. Conversely, only 2.72% of persons with CT findings not related to neurocysticercosis had positive EITB tests. CONCLUSIONS: Our study shows that an important proportion of individuals with epilepsy have radiologic or serologic evidence of T. solium infection, suggesting that neurocysticercosis is an important etiology for epilepsy in Colombia.

Diagnosis of paracoccidioidomycosis by dot immunobinding assay for antibody detection using the purified and specific antigen gp43.

The dot immunobinding assay, a rapid, visually read test, was adapted for serodiagnosis and follow-up of paracoccidioidomycosis (PCM). Purified gp43 antigen was tested before and after sodium metaperiodate treatment. To evaluate the assay, it was tested with sera from PCM, histoplasmosis, Jorge Lobo's disease, aspergillosis, candidiasis, and cryptococcosis patients and healthy subjects. Native gp43 gave positive results with all sera from PCM patients and weakly positive results with sera from Jorge Lobo's disease patients (31.3%). No false-positive results were obtained when periodate-treated gp43 was used as the antigen. These results indicate that the dot immunobinding test is sensitive, specific, economical, and fast for serodiagnosis and follow-up studies of PCM.

[The rapid diagnosis of rubella and measles by the dot immunoassay method]. / Diagnóstico rápido de rubéola y sarampión por el método de inmunoensayo en mancha.

A procedure is described for the routine laboratory identification of IgM or/and IgG antibodies to measles and rubella simultaneously. A rapid dot-immunobinding assay on nitrocellulose was compared with ELISA systems. 58 serum samples from patients with an exanthematous disease and 15 serum negative samples for both virus were studied. The type of antibody found in all samples was variable and was always related to the presence of immunity in each individual. However, all known negative samples were negative. When results were compared with commercially available ELISA systems or reference laboratories, we found an excellent correlationship including titers. We concluded that the dot-immunobinding assay is a rapid, specific, sensitive, reproducible and economic test that can be used simultaneously for identification of several antigens.