ABSTRACT
Background: Serological diagnosis of Strongyloides stercoralis is often limited by its low specificity due to cross-reactivity with other parasitic nematodes. Novel serological tests assumed to be more specific have been recently developed. The aim of our study was to compare two commercial tests based on different antigens for S. stercoralis diagnosis in humans from a non-endemic area. Methods: A retrospective laboratory-based study was conducted in the Hospital Universitario 12 de Octubre, Madrid, Spain. Samples from patients with a requested S. stercoralis serology from January 2013 to October 2016 were tested with two commercial enzyme-linked immunosorbent assay (ELISA) tests (crude larval suspension ELISA [CrAg-ELISA] and recombinant antigen ELISA [NIE-ELISA]). Sensitivity, specificity and predictive values were calculated using primary and composite gold standards. The κ index was calculated. Results: A total of 249 samples from 233 patients were tested (κ=0.735). The CrAg-ELISA yielded sensitivities from 89.2% (95% confidence interval [CI] 80.7 to 94.2) to 94.7% (95% CI 75.4 to 99.0) and the NIE-ELISA from 72.3% (95% CI 58.2 to 83.1) to 78.9% (95% CI 56.7 to 91.5). Specificity ranged from 72.3% (95% CI 58.2 to 83.1) to 89.3% (95% CI 83.1 to 93.4) for the CrAg-ELISA and from 85.1% (95% CI 72.3 to 92.6) to 93.6% (95% CI 88.2 to 96.6) for the NIE-ELISA. Conclusions: The NIE-ELISA is more specific than the CrAg-ELISA, but its low sensitivity limits its use in S. stercoralis screening. New diagnostic tests are needed for the diagnosis of S. stercoralis.
Subject(s)
Enzyme-Linked Immunosorbent Assay , Serologic Tests , Strongyloides stercoralis/immunology , Strongyloidiasis/diagnosis , Adolescent , Adult , Aged , Aged, 80 and over , Animals , Antibodies, Helminth/blood , Child , Child, Preschool , Female , Humans , Male , Middle Aged , Reference Standards , Retrospective Studies , Sensitivity and Specificity , Spain/epidemiology , Strongyloidiasis/immunology , Young AdultABSTRACT
Los datos sobre prevalencia de la eosinofilia importada entre viajeros e inmigrantes la sitúan entre un 8%-28,5%. El estudio etiológico es en ocasiones complejo, y en función de lo exhaustivo del estudio y de la población analizada, se ha podido identificar una causa parasitaria en el 17%-75,9% de los individuos. Entre las dificultades que se encuentran para comparar los estudios están la heterogeneidad de las poblaciones estudiadas, el tipo de recogida (prospectiva/retrospectiva) y distintos protocolos diagnósticos. En este documento se detallan las recomendaciones del grupo de expertos de la Sociedad Española de Medicina Tropical y Salud Internacional (SEMTSI) para el diagnóstico y tratamiento de la eosinofilia importada (AU)
According to published data, prevalence of imported eosinophilia among travellers and immigrants is set between 8% and 28.5%. Etiological diagnosis is often troublesome, and depending on the depth of the study and on the population analyzed, a parasitic cause is identified in 17% to 75.9% of the individuals. Among the difficulties encountered to compare studies are the heterogeneity of the studied populations, the type of data collection (prospective/retrospective) and different diagnostic protocols. In this document the recommendations of the expert group of the Spanish Society of Tropical Medicine and International Health (SEMTSI) for the diagnosis and treatment of imported eosinophilia are detailed (AU)
Subject(s)
Humans , Male , Female , Eosinophilia/diagnosis , Eosinophilia/therapy , Emigrants and Immigrants/statistics & numerical data , Consensus Development Conferences as Topic , Helminthiasis/diagnosis , Helminths , Helminths/isolation & purification , Immunoglobulin E/analysis , Sanitary Control of Travelers , Societies, Medical/organization & administration , Societies, Medical/standards , Prospective Studies , Travelers' Health , Helminthiasis/epidemiology , Retrospective Studies , Eosinophilia/classification , Enzyme-Linked Immunosorbent Assay/methods , Blotting, Western , Immunoenzyme TechniquesABSTRACT
INTRODUCTION: Trichinellosis is a helminth infection having a wide geographical distribution. It is acquired by ingestion of raw or undercooked meat infected with Trichinella spp. The present work reviews the human trichinellosis outbreaks recorded in Spain during 1990-2001, taking into account both the geographical distribution and source of the infection. METHODS: The parasite was isolated from suspected meats with the digestion technique. Molecular characterization of Trichinella isolates was done by random amplified polymorphic DNA (RAPD) analysis and Western-blot with US5 and US9 monoclonal antibodies. Anti-Trichinella antibodies in the patients' sera were investigated by indirect immunofluorescence (IIF). RESULTS: A total of 49 trichinellosis outbreaks were detected in Spain during 1990-2001, 75.5% produced by ingestion of infected wild boar, 14.3% by infected domestic pig and 10.2% by an unknown source. Of the 49 outbreaks, 21 were followed up in our laboratory. We were able to perform molecular identification of the Trichinella species involved in 13 outbreaks, with 61.5% produced by T. britovi and 38.5% by T. spiralis. Serological diagnosis of the trichinellosis patients by IIF allowed confirmation of helminth infection. CONCLUSIONS: With the use of molecular markers, T. spiralis and T. britovi were identified as the causative organisms in trichinellosis outbreaks detected in Spain during 1990-2001. These results reveal the importance of T. britovi in Spanish public health.
