Serological monitoring of progression of alveolar echinococcosis with multiorgan involvement by use of recombinant Em18

Histopathological assessment of the viability of hepatic alveolar echinococcosis

AIMS

Infections by the larval stage of the tape worms Echinococcus multilocularis and Echinococcus granulosus s.l. are potentially fatal zoonoses affecting humans as dead-end hosts. Histopathological evaluation of hepatic echinococcosis is an integral part of patient management, including the distinction between alveolar (AE) and cystic echinococcosis (CE), which are associated with different disease courses and treatments. To improve histopathological assessment of Echinococcus lesions, we aimed to develop robust criteria to evaluate their viability and decay.

METHODS AND RESULTS

Histomorphological criteria for determining parasitic viability based on the morphology of parasite structures and different stages of their decay were defined based on a clinically and molecularly defined cohort comprising 138 specimens from 112 patients (59 AE and 53 CE); 618 AE lesions were assessed for histopathological viability comparing haematoxylin and eosin (H&E) staining with mAbEm18 and mAbEm2G11 immunostaining. Moreover, parasite viability was systematically mapped in cross-sections of five additional AE lesions. Protoscoleces in CE and AE displayed variable states of degeneration. Albendazole had no significant effect on the morphology of parasite structures. Viability assessment revealed high agreement between H&E and mAbEm18, but not mAbEm2G11 staining, suggesting mAbEm18 staining as reliable for parasite viability assessment. H&E and mAbEm18 staining displayed a central-peripheral gradient of parasite viability and decay across parasitic lesions, with decayed cystic lesions located more towards the lesion centre while the most viable cystic lesions were located more peripherally.

CONCLUSIONS

Histopathological criteria corroborated by mAbEm18 staining provide a simple and reliable tool to assess the viability of AE lesions, knowledge of which is a valuable decision-making tool for further treatment.

One-tube nested MGB Probe Real-time PCR assay for detection of Echinococcus multilocularis infection in plasma cell free DNA

INTRODUCTION

The main objective of this study was to develop a One-tube nested MGB probe real-time PCR Assay for detecting Echinococcus multilocularis infection in human plasma cell free DNA (cfDNA).

METHODS

cfDNA was extracted from 10 E.m.-infected patients using a NucleoSnap DNA Plasma Kit and characterized by genomic sequencing. We designed nested PCR primers and MGB probe for Echinococcus multilocularis detection. The specificity, sensitivity and reproducibility of this assay were analyzed, and its validity was confirmed in 13 early stage clinical samples.

RESULTS

Several Echinococcus multilocularis-specific sequences were detected in the cfDNA of E.m.-infected patients, and CBLO020001206.1 was selected as the candidate sequence. We designed the primers and probe for the one tube nested real-time PCR. No cross-reactions with E.g. were observed. The detection limit was as low as 1 copy for Echinococcus multilocularis. The coefficients of variation were lower than 5% in intra- and inter-assays. 11 out of 13 patients were positive with nested MGB Probe PCR Assay and 3 patients were positive without outer primer in early stage Alveolar Echinococcosis pateints.

CONCLUSION

The one-tube nested MGB probe real-time PCR assay is a simple, rapid, and cost-effective method for detection of Echinococcus multilocularis infection in patients' Plasma DNA.

Serum platelet-derived growth factor-BB levels as a potential biomarker in assessing the metabolic activity of lesions in alveolar echinococcosis patients

BACKGROUND

Alveolar echinococcosis (AE) is a chronic disease caused by the larval stage of Echinococcus multilocularis. Assessing the metabolic activity of AE lesions is critical to evaluate disease progression and survey treatment options. There is an urgent need to identify more rapid, convenient, and non-invasive clinical detection methods to substitute the current techniques. Herein, we evaluated the viability of platelet-derived growth factor-BB (PDGF-BB) as a biomarker for detecting the metabolic activity of AE patients and their correlations with clinicopathological features of AE patients.

METHODS

Sera were collected from 28 AE patients and a homogenous cohort of 28 healthy individuals. The concentration of serum PDGF-BB homodimers (sPDGF-BB) was assessed via an enzyme-linked immunosorbent assay (ELISA). Liver tissue samples were obtained from a consecutive series of 28 AE patients who underwent surgical resection. Thereafter, we determined the expression levels of local PDGF-BB and platelet-derived growth factor receptor-β (PDGFR-β) through immunohistochemistry (IHC). Correlations of PDGF-BB expression levels with clinicopathological features of AE patients were analyzed using SPSS.

RESULTS

The concentrations of sPDGF-BB were significantly lower in AE patients (p < 0.0001), particularly in High Metabolically Active AE patients (HMAE) patients (p < 0.05). The expression levels of PDGF-BB and its receptor were both significantly higher in close liver tissue (CLT) in AE patients (p < 0.0001). We also found that metabolically active AE and sPDGF-BB are significantly negatively correlated (r = -0.624, p = 0.0004). Beside, the local expression levels of PDGF-BB was positively correlated with metabolic activity, PNM stage, and lesion size. Notably, the sPDGF-BB levels were proposed as a potential biomarker for assessing metabolic activity of AE, with 81.0% sensitivity and 85.7% specificity (95% confidence interval, p = 0.003).

CONCLUSIONS

Serum levels of PDGF-BB could be a simple, non-invasive, and quick biomarker for assessing the metabolic activity of lesions in AE patients.

Echinococcus granulosus Protoscolex DM9 Protein Shows High Potential for Serodiagnosis of Alveolar Echinococcosis

Alveolar echinococcosis (AE) caused by infection with E. multilocularis metacestode, represents one of the most fatal helminthic diseases. AE is principally manifested with infiltrative, proliferating hepatic mass, resembling primary hepatocellular carcinoma. Sometimes metastatic lesions are found in nearby or remote tissue. AE diagnosis largely depends on imaging studies, but atypical findings of imaging features frequently require differential diagnosis from other hepatic lesions. Serological tests may provide further evidence, while obtaining reliable AE materials is not easy. In this study, alternative antigens, specific to AE were identified by analyzing E. granulosus protoscolex proteins. An immunoblot analysis of E. granulosus protoscolex showed that a group of low-molecular-weight proteins in the range from 14 kDa to 16 kDa exhibited a sensitive and specific immune response to AE patient sera. Partial purification and proteomic analysis indicated that this protein group contained myosin, tubulin polymerization promoting protein, fatty-acid binding protein, uncharacterized DM9, heat shock protein 90 cochaperone tebp P-23, and antigen S. When the serological applicability of recombinant forms of these proteins was assessed using enzyme-linked immunosorbent assay, DM9 protein (rEgDM9) showed 90.1% sensitivity (73/81 sera tested) and 94.5% specificity (172/181 sera tested), respectively. rEgDM9 showed weak cross-reactions with patient sera from the transitional and chronic stages of cystic echinococcosis (3 to 5 stages). rEgDM9 would serve as a useful alternative antigen for serodiagnosis of both early- and advanced-stage AE cases.

Evaluation of Serological Markers in Alveolar Echinococcosis Emphasizing the Correlation of PET-CTI Tracer Uptake with RecEm18 and Echinococcus-Specific IgG

Human alveolar echinococcosis (AE), which is caused by the cestode Echinococcus (E.) multilocularis, is an epidemiologically relevant issue in modern medicine and still poses a diagnostic and therapeutic challenge. Since diagnosis mainly relies on imaging procedures and serological testing, we retrospectively and comparatively analyzed the performance of an Echinococcus IgG screening ELISA, whole serum IgE, and two specific confirmatory ELISA platforms using the defined E. multilocularis antigens Em2-Em18 (Em2+) and recombinant Em18 (recEm18). With special emphasis on the clinical usefulness of recEm18, we correlated the laboratory results with clinical characteristics and imaging findings in a large and well-characterized cohort of N = 124 AE patients, who were followed over several years after either surgical plus subsequent pharmacological treatment or pharmacotherapy alone. All patients had routinely received PET-CTI every two years. Our data reveal strong correlations for both Echinococcus IgG and recEm18 with tracer uptake in PET-CTI and parasitic lesion size and number, suggesting additional clinical usefulness of recEm18 for certain constellations only, while IgG and Em2+ still appear reasonable and sensitive screening methods for initial diagnosis of AE. With this study, we aim to contribute to further optimizing medical care of AE patients. For instance, it might be reasonable to consider the replacement of some PET-CTI follow-ups by imaging procedures with less radiation exposure or serological means alone. Further studies that clarify the correlation of serological markers with ultrasound criteria might be particularly useful, and further retrospective as well as prospective investigations are justified in this context.

Cardiac Hydatid Cyst Successfully Managed with Albendazole: A Case Report

Hydatid disease is a parasitic infection caused by tapeworm Echinococcus. It has a worldwide distribution, but it is endemic in certain geographic locations. Hydatid disease can almost involve any body organ. However, cardiac involvement is exceedingly rare. We report the case of young girl presenting with chest pain and shortness of breath. She had a history of renal hydatid cyst for which she underwent surgical resection. After thorough investigation, she was found to have a hydatid cyst involving the left ventricular wall. The patient's family refused surgical management, and she had received medical treatment in the form of albendazole which showed dramatic improvement in her condition. This case shed light on the importance of having a high index of suspicion for this condition, particularly in those patients with a history of hydatid cysts in other organs.

The usefulness of commercially available serological tests in the diagnosis and monitoring of treatment in patients with alveolar echinococcosis

Aim of the study

To assess the clinical usefulness of serological tests in the diagnosis and monitoring of treatment of patients with alveolar echinococcosis (AE).

Material and methods

The results of serological tests, i.e. Echinococcus multilocularis ELISA (Bordier Affinity Products) and Echinococcus Western Blot IgG (LDBIO Diagnostic), of 66 patients were analysed. Duration of follow-up was two years after diagnosis. In the second phase of the study 11 sera obtained from the patients undergoing surgical treatment, in whom the results of Echinococcus Western Blot IgG assay were still positive, were additionally tested with Anti-Echinococcus EUROLINE-WB (IgG) assay.

Results

Statistically significant negativization of the Echinococcus multilocularis ELISA test was observed in the group of patients who underwent radical surgery or liver transplantation. Negativization of Echinococcus Western Blot IgG assay results was observed in some patients, among both those who received conservative treatment and those who underwent surgery, but no statistically significant differences were found between treatment groups. In 54.5% of cases the Anti-Echinococcus EUROLINE-WB (IgG) test result was negative when the results of the Echinococcus Western Blot IgG assay were still positive.

Conclusions

Echinococcus multilocularis ELISA proved to be useful in assessing the activity of AE in a group of patients who underwent radical surgery or liver transplantation. The results of our study suggest that Anti-Echinococcus EUROLINE-WB (IgG) is a more dynamic test, which at the time of disappearance of AE activity becomes negative earlier.

Diagnostic and follow-up performance of serological tests for different forms/courses of alveolar echinococcosis

Diagnosis of alveolar echinococcosis (AE) is predominantly based on imaging procedures combined with immunodiagnostic testing. In the present study, we retrospectively analyzed the performance of four serological tests (EgHF-ELISA, Em2-ELISA, recEm18-ELISA and Em-Immunoblotting) for initial diagnosis and subsequent monitoring of AE patients. Overall, 101 AE patients were included, grouped according to treatment options and immune status as follows: (A) curative surgical treatment (n = 45 patients), (B) non-radical or palliative surgical treatment (n = 11), (C) benzimidazoles only (n = 20), (D) immunocompromised with radical surgical treatment (n = 11), (E) immunocompromised with benzimidazoles only (n = 4), and finally a group of 10 AE patients (F) that were considered to present so-called “abortive” lesions. Initial (i.e. pretreatment) ELISA-based diagnosis for patients in groups A to E revealed overall diagnostic sensitivities of 95% for EgHF, 86% for Em2, and 80% for recEm18, respectively. Comparatively, the diagnostic sensitivity of Em-Immunoblotting was higher with an overall value of 98%. In group F, only Em-Immunoblotting had an excellent diagnostic sensitivity (100%), whereas the ELISAs had poor sensitivities of 30% (EgHF- and Em2-ELISA) or even 0% (recEm18-ELISA).

Serological monitoring of AE patients showed a clear association between a curative development of disease (induced either by surgery or benzimidazole medication) and a negativization in the ELISAs. This effect was most pronounced for the recEm18-ELISA, where 56% negativized following diagnosis/treatment, as compared to 36% for the EgHF-ELISA, and 37% for the Em2-ELISA, respectively. After radical surgery, the mean time until negativization in the recEm18-ELISA was 2.4 years (SD 1.6). This was significantly shorter than the mean 3.9 years (SD 2.5) in those AE patients with non-radical, palliative surgery or ABZ treatment who were able to negativize during the study period (p = 0.048).

Conclusively, Em-Immunoblotting appears as the most sensitive test to diagnose active as well as inactive (“abortive”) AE-cases. The inclusion of the ELISAs completes the initial diagnostic picture and offers valuable additional information. Conversely, recEm18-ELISA appears as the currently best serological tool to monitor a regressive and putatively curative course of AE in treated patients.

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EgHF-ELISA plus Em-Immunoblotting results in most sensitive initial AE serodiagnosis.

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Em2- and recEm18-ELISA allow differentiation between AE and CE.

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recEm18-ELISA is currently the best monitoring test for assessing curative course of AE.

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Presumably inactive (“abortive”) AE cases were all positive by Em-Immunoblotting.

Serological validation of an alveolar echinococcosis rat model with a single hepatic lesion

Serology is important for the diagnosis and follow-up of human alveolar echinococcosis (AE). However, patient conditions are highly variable among those with AE, and antibody responses in serological follow-up have not been well-defined. We recently described a new AE rat model established by implantation of small AE tissue into a single arbitrary location in the liver; no metastasis and dissemination were observed. In the present study, we examined the serological characteristics in our rat model before and after surgical treatment. The results showed that antibody responses against crude antigens were increased at one month after transplantation and similar to those of other model animals. For the antigen Em18, antibody responses were slower in our rat model than in other animal models. After surgical resection, changes in antibody responses against Em18 were similar to those observed in human patients with AE. Because of the slow growth of lesions, establishment of a single hepatic lesion and patterns of antibody responses, our rat model may be useful for clarifying follow-up serodiagnoses in human AE and determining the mechanisms of multi-organ involvement by primary infection with oncospheres rather than metastasis.

Evaluation of immunochromatographic test for the detection of antibodies against Echinococcosis granulosus

BACKGROUND

Echinococcosis in humans is a disease caused by the larvae of Echinococcus granulosus (E. granulosus) and Echinococcus multilocularis (E. multilocularis). Serological tests are valuable, especially in the clarification of unexplained clinical findings and imaging methods. For this reason, indirect hemagglutination (IHA), latex agglutination, immunoelectrophoresis, immunoblotting, immuno-enzymatic tests, indirect fluorescence antibody test (IFAT), and enzyme-linked immunosorbent assay (ELISA) are used. The purpose of this study was to investigate the value of an immunochromatographic test (ICT) specific for E. granulosus antibodies in the diagnosis of echinococcosis.

MATERIAL/METHODS

ICT evaluated 102 cases of cystic echinococcosis, 38 cases of other parasitic diseases, and 50 healthy individuals. ELISA (DRG, Germany) that detects IgG antibodies specific for E. granulosus was used as the reference method.

RESULTS

The sensitivity, specificity, and positive and negative predictive values of ICT were 96.8%, 87.5%, 98.9%, and 70%, respectively. Diagnostic value was 96.1%. No significant differences and high degrees of agreement were found between ELISA and immunochromatographic test for cystic echinococcosis. Serum samples included 4 taeniasis, 2 leishmaniasis, and 2 healthy individuals were diagnosed to be positive with immunochromatographic test.

CONCLUSIONS

The ability of test to give fast results without need for equipment, devices, and specific storage conditions is an advantage. This test may be used due to its advantages in endemic regions for screening and diagnostic purposes.

Comparison of the serological tests ICT and ELISA for the diagnosis of alveolar echinococcosis in France

Serological diagnosis of alveolar echinococcosis (AE) is a key element for efficient patient treatment management. A rapid immunochromatography test kit (ICT) using the recombinant Em18 antigen (rEm18) was recently developed. The aim of our study was to assess this test on a panel of sera from French patients with alveolar echinococcosis and control patients. In a blind test, a total of 112 serum samples were tested including samples of AE (n = 30), cystic echinococcosis [CE] (n = 15), and polycystic echinococcosis [PE] (n = 1). For the comparison, 66 sera from patients with hepatocarcinoma, fascioliasis, toxocariasis, Caroli’s disease, or autoimmune chronic active hepatitis were used. The diagnostic test sets we used were the rEm18-ICT and two validated ELISAs with rEm18 and Em2-Em18 antigens, respectively. For the ICT, 27/30 sera from AE patients, 4/15 sera from CE patients and the PE patient serum were positive. One serum from the control panel (toxocariasis) was positive for the ICT. The rEm18-ICT sensitivity (90.0%) and specificity (92.7%) for detection of Em18-specific antibodies confirmed it as a relevant tool for AE diagnosis. The rEm18-ELISA had a sensitivity of 86.7% and specificity of 91.5%, and the Em2-Em18-ELISA had a sensitivity of 96.7% and specificity of 87.8%. However, when AE patient sera are recorded as weak in intensity with the ICT, we recommend a double reading and use of a reference sample if the ICT is used for patient follow-up.

Serological and molecular characteristics of the first Korean case of Echinococcus multilocularis

In December 2011, we reported an autochthonous case of Echinococcus multilocularis infection in a 42-year-old woman in Korea. The diagnosis was based on histopathological findings of the surgically resected liver cyst. In the present study, we evaluated the serological and molecular characteristics of this Korean E. multilocularis case. The patient's serum strongly reacted with affinity-purified native Em18 and recombinant Em18 antigens (specific for E. multilocularis) but negative for recombinant antigen B8/1 (reactive for Echinococcus granulosus). In immunoaffinity chromatography, the serum also strongly reacted with E. multilocularis and only weakly positive for E. granulosus. We determined the whole nucleotide sequence of cox1 (1,608 bp) using the paraffin-embedded cystic tissue which was compared with E. multilocularis isolates from China, Japan, Kazakhstan, Austria, France, and Slovakia. The Korean case showed 99.8-99.9% similarity with isolates from Asia (the highest similarity with an isolate from Sichuan, China), whereas the similarity with European isolates ranged from 99.5 to 99.6%.

Nothing is perfect! Trouble-shooting in immunological and molecular studies of cestode infections

This personal review focuses on ways to approach and overcome some of the more common issues encountered while studying cestode zoonoses. The information presented here is based on the author's own experiences with immunological and molecular approaches for the detection of these parasites. There are many incongruities between immunological and molecular studies due to biased work. Nothing is perfect. Indirect approaches using either immunological, or even molecular tools, are limited without confirmation from direct evidence of infection. The dilemma of whether developing countries should develop their own diagnostic tests or rely on commercially available kits is also discussed.

Challenges for diagnosis and control of cystic hydatid disease

This paper is based on the experience of the authors, with the aim to define the challenges for Echinococcus granulosus (E.g./CE) diagnosis and control for those countries that may now or in the future be contemplating control of hydatid disease. A variety of methods are available for diagnosis in humans but a universal gold standard is lacking. Diagnosis in definitive hosts can avoid necropsy by the use of methods such as coproantigen detection but test performance is variable between populations. A sylvatic cycle adds challenges in some countries and the epidemiology of the parasite in these hosts is poorly understood. Control by solely administering praziquantel to dogs is not effective in developing countries where the disease is endemic. Additional avenues to pursue include the instigation of participatory planning, use of an existing vaccination for intermediate hosts and development of a vaccine and long-acting anthelmitic implants for definitive hosts. Promoting public acceptance of control of the dog population by humane euthanasia and reduced reproduction is also essential.

Hydatid disease in childhood: revisited report of an interesting case

Hydatid disease is a zoonosis caused by the tapeworm of Echinococcus spp. The disease is widely endemic in many sheep and cattle rearing locales. However, hydatidosis does not remain restricted to endemic geographical locales anymore but rather is a global health concern. It is a major public health burden causing significant morbidity and mortality. Echinococcus granulosus involvement in children has a different pattern than adults. Children of all age groups are susceptible and localization of the disease in the lungs is more commonly seen. Multiple liver cysts in the paediatric age group is relatively uncommon. We report an interesting case of multiple liver cysts in a 5-year old boy which was diagnosed as hydatid cysts on histopathological examination.

Should possible recurrence of disease contraindicate liver transplantation in patients with end-stage alveolar echinococcosis? A 20-year follow-up study

Liver transplantation (LT) is currently contraindicated in patients with residual or metastatic alveolar echinococcosis (AE) lesions. We evaluated the long-term course of such patients who underwent LT and were subsequently treated with benzimidazoles. Clinical, imaging, serological, and therapeutic data were collected from 5 patients with residual/recurrent AE lesions who survived for more than 15 years. Since 2004, [(18) F]-2-fluoro-2-deoxyglucose (FDG)-positron emission tomography (PET) images were available, and the levels of serum antibodies (Abs) against Echinococcus multilocularis-recombinant antigens were evaluated. Median survival time after LT was 21 years. These patients were from a prospective cohort of 23 patients with AE who underwent LT: 5 of 8 patients with residual/recurrent AE and 4 of 9 patients without residual/recurrent AE were alive in September 2009. High doses of immunosuppressive drugs, the late introduction of therapy with benzimidazoles, its withdrawal due to side effects, and nonadherence to this therapy adversely affected the prognosis. Anti-Em2(plus) and anti-rEm18 Ab levels and standard FDG-PET enabled the efficacy of therapy on the growth of EA lesions to be assessed. However, meaningful variations in Ab levels were observed below diagnostic cutoff values; and in monitoring AE lesions, images of FDG uptake taken 3 hours after its injection were more sensitive than images obtained 1 hour after its injection. In conclusion, benzimidazoles can control residual/recurrent AE lesions after LT. Using anti-rEm18 or anti-Em2(plus) Ab levels and the delayed acquisition of FDG-PET images can improve the functional assessment of disease activity. The potential recurrence of disease, especially in patients with residual or metastatic AE lesions, should not be regarded as a contraindication to LT when AE is considered to be lethal in the short term.

Immunochromatographic test with recombinant Em18 antigen for the follow-up study of alveolar echinococcosis

The performance of a rapid and simple immunochromatographic test (ICT) with recombinant Em18 (rEm18) antigen for serological follow-up of Echinococcus multilocularis infection was evaluated by comparison with that of an enzyme-linked immunosorbent assay (ELISA) with rEm18, using serum samples from patients who underwent surgery and/or received antiparasitic chemotherapy. The degree of Em18-band intensity on the ICT correlated highly with the absorbance value obtained by the ELISA. The kinetics of antibody levels obtained by the ICT paralleled those of the ELISA. These data suggest that the ICT has high potential as an easy-to-handle, fast, and reliable follow-up tool to monitor the status of alveolar echinococcosis in different stages.

Immunoglobulin G subclass responses to recombinant Em18 in the follow-up of patients with alveolar echinococcosis in different clinical stages

In this study, we compared the sequential responses of immunoglobulin G (IgG) subclasses to the diagnostic antigen Em18 in sera from patients with alveolar echinococcosis. A total of 225 sera from 36 patients at different clinical stages according to the WHO-PNM staging system were tested. The antibody responses were measured for cohorts with resected and unresected parasitic lesions by enzyme-linked immunosorbent assays (ELISA). Total IgG and, to a lesser extent, IgG4 antibody levels against Em18 correlated with all PNM stages before treatment, whereas levels of IgG2 were low and IgG3 was undetectable. Antibody kinetics, however, depended on the treatment rather than on the PNM stage. For some patients, after curative surgery, IgG1 antibodies dropped below the cutoff earlier than other antibodies, followed by total IgG and IgG4 within 18 months. For some patients with recurrences after surgery, IgG1 and IgG4 reappeared, whereas patients with unresectable lesions but stable disease showed steady declines in the levels of all antibodies, and IgG1 became undetectable in some patients. Additional testing of IgE responses to Em18 showed constantly low levels at all stages and in all cohorts.

Histopathological, serological, and molecular confirmation of indigenous alveolar echinococcosis cases in Mongolia

Alveolar echinococcosis cases diagnosed histopathologically in 2002, 2006, 2007, and 2009 in Ulaanbaatar, Mongolia were reconfirmed by evaluating the cytochrome c oxidase subunit I gene of mitochondrial DNA. The most recent three cases using paraffin-embedded and ethanol-fixed specimens revealed that one was of the "Asian" haplotype, whereas two others were of the "Inner Mongolian" type. All patients were born in the western provinces of Mongolia, they never resided outside of Mongolia, and they were given a preliminary diagnosis of malignant hepatic tumor or abscess. The most recent two cases were also confirmed serologically to be active alveolar echinococcosis.

Mongolian and Japanese Joint Conference on "Echinococcosis: diagnosis, treatment and prevention in Mongolia" June 4, 2009

The first Mongolian-Japanese Joint Conference on "Echinococcosis: diagnosis, treatment and prevention in Mongolia" was held in Ulaanbaatar on June 4^th, 2009. It was the first chance for Mongolian experts (clinicians, pathologists, parasitologists, biologists, epidemiologists, veterinarians and others working on echinococcosis) joined together. Increase in the number of cystic echinococcosis (CE) cases year by year was stressed. CE in children may be more than adult cases. Alveolar echinococcosis was suspected chronic malignant hepatic tumors or abscesses. Main discussion was as to how to introduce modern diagnostic tools for pre-surgical diagnosis, how to establish the national system for the data base of echinococcosis with the establishment of a network system by experts from different areas. The importance of molecular identification of the parasites in domestic and wild animals was also stressed.

Specific IgG responses to recombinant antigen B and em18 in cystic and alveolar echinococcosis in china

An understanding of the correlation of the specific antibody responses and the disease phase is essential in evaluating diagnostic values of immunological tests in human echinococcosis. In this study, 422 echinococcosis patients diagnosed by ultrasonography, including 246 with cystic echinococcosis (CE), 173 with alveolar echinococcosis (AE), and 3 with dual infection, were tested for specific IgG in sera against recombinant AgB (rAgB) and recombinant Em18 (rEm18) in an enzyme-linked immunosorbent assay. As a result, rAgB-specific antibody was detected in 77.6% of CE and 86.1% of AE patients, while rEm18-specific antibody was present in 28.9% of CE and 87.3% of AE patients. Additionally, all three patients with dual infection exhibited specific antibodies responding to rAgB and rEm18. Further analysis revealed that rAgB-specific antibody was elevated in a significantly greater proportion (87.3%) of CE patients with cysts at active or transitional stages (CE1, CE2, or CE3), compared to 54.8% of other patients with cysts at an early or an inactive stage (CL or CE4 or CE5). Furthermore, rAgB-specific antibody was detected in 95.6% of CE2 cases, which was statistically greater than that (73.7%) in CE1 patients. Although rEm18-specific antibody was elevated in 28.9% of CE patients, the positive reaction was much weaker in CE than in AE cases. Serum levels and concentrations of rEm18-specific antibody were further indicated to be strongly disease phase correlated in AE patients, with positive rates of 97.4% in cases with alveolar lesions containing central necrosis and 66.7% in patients with early alveolar lesions that measured </=5 cm.