Serological diagnosis of echinococcosis: the diagnostic potential of native antigens

Abstract

PURPOSE: Human alveolar (AE) and cystic echinococcosis (CE) caused by the metacestode stages of Echinococcus multilocularis and E. granulosus, respectively, lack pathognomonic clinical signs. Diagnosis therefore relies on the results of imaging and serological studies. The primary goal of this study was to evaluate the efficacy of several easy-to-produce crude or partially purified E. granulosus and E. multilocularis metacestode-derived antigens as tools for the serological diagnosis and differential diagnosis of patients suspicious for AE or CE. METHODS: The sera of 51 treatment-naïve AE and 32 CE patients, 98 Swiss blood donors and 38 patients who were initially suspicious for echinococcosis but suffering from various other liver diseases (e.g., liver neoplasia, etc.) were analysed. RESULTS: According to the results of enzyme-linked immunosorbent assays (ELISA), metacestode-derived antigens of E. granulosus had sensitivities varying from 81 to 97% and >99.9% for the diagnosis of CE and AE, respectively. Antigens derived from E. multilocularis metacestodes had sensitivities ranging from 84 to 91% and >99.9% for the diagnosis of CE and AE, respectively. Specificities ranged from 92 to >99.9%. Post-test probabilities for the differential diagnosis of AE from liver neoplasias, CE from cystic liver lesions, and screening for AE in Switzerland were around 95, 86 and 2.2%, respectively. Cross-reactions with antibodies in sera of patients with other parasitic affections (fasciolosis, schistosomosis, amebosis, cysticercosis, and filarioses) did occur at variable frequencies, but could be eliminated through the use of confirmatory testing. CONCLUSIONS: Different metacestode-derived antigens of E. granulosus and E. multilocularis are valuable, widely accessible, and cost-efficient tools for the serological diagnosis of echinococcosis. However, confirmatory testing is necessary, due to the lack of species specificity and the occurrence of cross-reactions to other helminthic diseases. Abstract Purpose Human alveolar (AE) and cystic echinococcosis (CE) caused by the metacestode stages of Echinococcus multilocularis and E. granulosus, respectively, lack pathognomonic clinical signs. Diagnosis therefore relies on the results of imaging and serological studies. The primary goal of this study was to evaluate the efficacy of several easy-to-produce crude or partially purified E. granulosus and E. multilocularis metacestode-derived antigens as tools for the serological diagnosis and differential diagnosis of patients suspicious for AE or CE. Methods The sera of 51 treatment-naïve AE and 32 CE patients, 98 Swiss blood donors and 38 patients who were initially suspicious for echinococcosis but suffering from various other liver diseases (e.g., liver neoplasia, etc.) were analysed. Results According to the results of enzyme-linked immunosorbent assays (ELISA), metacestode-derived antigens of E. granulosus had sensitivities varying from 81 to 97% and [99.9% for the diagnosis of CE and AE, respectively. Antigens derived from...

Intense Focus of Alveolar Echinococcosis, South Kyrgyzstan

“…We detected specific IgG from collected serum in 3 genus-specific ELISAs based on E. granulosus hydatid fluid, native protoscolex antigens, and antigen B ( 6 ). Specific antibodies against E. multilocularis were demonstrated using affinity purified Em2G11 antigen ( 6 ) and the recombinant Em18 antigen ( 7 ).…”

Diagnostics in cystic echinococcosis: Serology versus ultrasonography

“…Cystic lesions of the liver are detected by means of diagnostic imaging methods, such as ultrasonography, magnetic resonance imaging (MRI), or computed tomography (CT) (10). The diagnosis of cystic echinococcosis using serological methods remains controversial (11). Serological methods currently employed in the diagnosis of CE include the enzyme-linked immunosorbent assay (ELISA), the indirect hemagglutination test (IHA), the latex agglutination tests, and immunoblots (12).…”

Echinococcosis

“…Reported diagnostic performances for CE are extremely variable: sensitivity 80-99 % and specificity 60-97 % for HCF and sensitivity 38-93 % and specificity 80-100 % for native purified or recombinant proteins (Carmena et al 2006;Eckert and Deplazes 2004;Barbieri et al 1998;Hernandez-Gonzalez et al 2008Lorenzo et al 2005;Ortona et al 2000;Poretti et al 1999;Schweiger et al 2012;Tawfeek et al 2011;Virginio et al 2003;Zhang et al 2003a;Gonzalez-Sapienza et al 2000;Jiang et al 2012;Rott et al 2000). On the contrary, serology is positive in more than 90 % of immunocompetent AE patients.…”

“…2. Cross-reactivity occurs with other helminthiases (especially cestodes) or more rarely with nonparasitic diseases (Poretti et al 1999;Zarzosa et al 1999;Gonzalez-Sapienza et al 2000;Hernandez-Gonzalez et al 2008de la Rue et al 2010;Liance et al 2000;Schweiger et al 2012;Lin et al 2013). Cross-reactivity with Taenia solium cysticercosis occurs even with very specific assays such as immunoblot (Moro et al 1992).…”

“…Cross-reactivity with Taenia solium cysticercosis occurs even with very specific assays such as immunoblot (Moro et al 1992). The high rate of cross-reactivity (50-100 %) between CE and AE is a problem where the two infections are co-endemic (de la Rue et al 2010;HernandezGonzalez et al 2008;Li et al 2010;Poretti et al 1999;Schweiger et al 2012). The different band pattern in HCF IB may discriminate between the two species in about 75 % of cases (Liance et al 2000); however, more specific tests for AE should be applied in case of high suspicion such as serology based on Em2-Em18 antigens (15 % cross-reactions with CE) and microscopic/PCR analysis of parasitic material Wang et al 2013).…”