Metabolic viability assessment of cystic echinococcosis using high-field 1H MRS of cyst contents

Evaluating diagnostic performance: A comparative analysis of cell-free DNA and serological test in hepatic cystic Echinococcosis

Cystic Echinococcosis (CE) is a zoonotic disease caused by Echinococcus granulosus sensu lato. Diagnosing CE primarily relies on imaging techniques, and there is a crucial need for an objective laboratory test to enhance the diagnostic process. Today, cell-free DNAs (cfDNAs) have gained importance regarding their biomarker potential. This study aims to investigate the diagnostic capabilities of different cfDNA targets (Echinococcus-specific repeat sequences (mgs-4 and mgs-12) and partial fragment of repetitive sequence (EG1 Hae III)) and evaluate their diagnostic effectiveness when compared to a frequently used commercial E.granulosus-specific IgG ELISA. Seventy-six confirmed hepatic CE patients and healthy controls were included in the study. The EG1 Hae III region was assessed using nested PCR, whereas real-time PCR was employed to investigate other cfDNA targets. Analysis of the cfDNA-targeted tests indicated that mgs-4 demonstrated the highest diagnostic efficacy in distinguishing CE patients from healthy controls, achieving a sensitivity of 60.5% (p = 0.002). Combining ELISA with the mgs-4 target led to an increased sensitivity of 72.4% for distinguishing between CE patients and the control group. The sensitivity rates for ELISA and the three cfDNA targets varied among the groups. Active CE patients showed sensitivity rates of 52.9%, 52.9%, 23.5%, and 52.9% for ELISA, mgs-4, mgs-12, and EG1 Hae III assays, respectively. In contrast, inactive cyst patients displayed sensitivity rates of 21.4%, 66.7%, 19%, and 42.9% for the corresponding assays. The mgs-4, either alone or in combination with ELISA, demonstrated notably higher sensitivity values for CE diagnosis in all group comparisons compared to serology.

Identification of serum biomarkers for cystic echinococcosis in sheep through untargeted metabolomic analysis using LC-MS/MS technology

BACKGROUND

Echinococcosis is a zoonotic disease caused by an Echinococcus tapeworm infection. While diagnostic methods for humans often rely on ultrasound imaging and immunodiagnostic techniques, diagnosis in intermediate hosts typically has no widely used diagnostic markers, hampering disease control efforts.

METHODS

The differences in serum metabolites of sheep infected with Echinococcus granulosus and a control group were analyzed using ultrahigh-performance liquid chromatography (UHPLC) separation with tandem mass spectrometry (MS/MS) detection. This provided a basis for the early diagnosis and pathogenetic study of cystic echinococcosis (CE) in intermediate hosts at the metabolomics level. Orthogonal projections to latent structures-discriminant analysis (OPLS-DA) were used to analyze different metabolites in the serum of the two groups. The differentially abundant metabolites were entered into the MetaboAnalyst 5.0 online analysis website for processing, and the top-15-ranked metabolic pathways were set to produce bubble plots and differential abundance score plots, with a significant difference of P < 0.05 and a false discovery rate (FDR) < 0.1 as the screening conditions.

RESULTS

Data analyses of serum samples from both groups identified a total of 1905 significantly different metabolites, where 841 metabolites were upregulated and 1064 metabolites were downregulated. Twelve metabolites were significantly upregulated and 21 metabolites were significantly downregulated in the experimental group. Then, the 1,7-dihydroxyxanthone, 2-methylbutyrylglycine, 3,3-dimethylglutaric acid, 5,12-dihydroxy-6,8,10,14,17-eicosapentaenoic acid, 9-hydroperoxy-10E,12Z,15Z-octadecatrienoic acid, and trimethylamine N-oxide 6 metabolites were selected as diagnostically valuable candidate biomarkers (area under the curve [AUC] > 0.7). These differential metabolites are involved in various metabolic pathways, including amino acid metabolites (arginine, L-isoleucine, L-valine) and fatty acid metabolism (fenugreek, arachidonic acid, linolenic acid). Compared with the control group, sheep in the CE group had increased serum levels of fenugreek acid, while all other metabolites such as glycine showed significantly reduced serum levels (P < 0.01).

CONCLUSIONS

Through non-targeted metabolomic analysis of the serum of CE-infected sheep, differential metabolites closely related to amino acid metabolism and the fatty acid metabolism pathway were identified. These differentially abundant metabolites can serve as biomarkers for diagnosing CE infection in intermediate sheep hosts.

Anti-echinococcal effect of metformin in advanced experimental cystic echinococcosis: reprogrammed intermediary carbon metabolism in the parasite

Metformin, a safe biguanide derivative with antiproliferative properties, has shown antiparasitic efficacy against the Echinococcus larval stage. Hence, we assessed the efficacy of a dose of 250 mg kg-1 day-1 in experimental models of advanced CE, at 6 and 12 months post-infection with oral and intraperitoneal administration, respectively. At this high dose, metformin reached intracystic concentrations between 0.7 and 1.7 mM and triggered Eg-TOR inhibition through AMPK activation by AMP-independent and -dependent mechanisms, which are dependent on drug dose. Cystic metformin uptake was controlled by increased expression of organic cation transporters in the presence of the drug. In both experimental models, metformin reduced the weight of parasite cysts, altered the ultrastructural integrity of their germinal layers, and reduced the intracystic availability of glucose, limiting the cellular carbon and energy charge and the proliferative capacity of metacestodes. This glucose depletion in the parasite was associated with a slight increase in cystic uptake of 2-deoxiglucose and the transcriptional induction of GLUT genes in metacestodes. In this context, drastic glycogen consumption led to increased lactate production and altered intermediary metabolism in treated metacestodes. Specifically, the fraction of reducing soluble sugars decreased twofold, and the levels of non-reducing soluble sugars, such as sucrose and trehalose, were modified in both cystic fluid and germinal cells. Taken together, our findings highlight the relevance of metformin as a promising candidate for CE treatment and warrant further research to improve the therapeutic conditions of this chronic zoonosis in humans.

The Diagnostic Challenge of Cystic Echinococcosis in Humans: First Assessment of Underreporting Rates in Mongolia

Cystic echinococcosis (CE), caused by the larval stage of Echinococcus granulosus, is significantly underreported in Mongolia due to geographical remoteness, a lack of early diagnostics, and poor clinical management. This study aimed to provide a more accurate estimate of CE in Mongolia by comparing data from surgical (reported) and diagnosed (unreported) cases and assessing the challenges faced by rural doctors in disease management and surveillance. We collected data on surgical cases hospitalized between 2006 and 2016 and newly diagnosed CE cases in 2016 from eight provinces. Using a quasi-Poisson regression model, we extrapolated the collected data to estimate the number of diagnosed cases for the entire country. Additionally, forty health professionals from all 21 provinces rated local clinical management for CE through a questionnaire. The results reveal that surgical cases (2.2 per year) represent only one-eighth of diagnosed cases (15.9 per year). The laboratory facilities, disease reporting, and cyst classification usage scored below 2. These results highlight the significant underreporting of CE in Mongolia and urge human and animal health experts, along with policymakers, to invest in combating CE, particularly in remote provincial areas. This study also emphasizes the need for standard clinical management involving cyst classification according to the WHO-IWGE and seamless integration of CE reporting and monitoring mechanisms, which can significantly contribute to the national and global burden estimation of CE.

Treatment of uncomplicated hepatic cystic echinococcosis (hydatid disease)

BACKGROUND

Cystic echinococcosis is a parasitic infection mainly impacting people living in low- and middle-income countries. Infection may lead to cyst development within organs, pain, non-specific symptoms or complications including abscesses and cyst rupture. Treatment can be difficult and varies by country. Treatments include oral medication, percutaneous techniques and surgery. One Cochrane review previously assessed the benefits and harms of percutaneous treatment compared with other treatments. However, evidence for oral medication, percutaneous techniques and surgery in specific cyst stages has not been systematically investigated and the optimal choice remains uncertain.

OBJECTIVES

To assess the benefits and harms of medication, percutaneous and surgical interventions for treating uncomplicated hepatic cystic echinococcosis.

SEARCH METHODS

We searched CENTRAL, MEDLINE, two other databases and two trial registries to 4 May 2023. We searched the reference lists of included studies, and contacted experts and researchers in the field for relevant studies.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) in people with a diagnosis of uncomplicated hepatic cystic echinococcosis of World Health Organization (WHO) cyst stage CE1, CE2, CE3a or CE3b comparing either oral medication (albendazole) to albendazole plus percutaneous interventions, or to surgery plus albendazole. Studies comparing praziquantel plus albendazole to albendazole alone prior to or following an invasive intervention (surgery or percutaneous treatment) were eligible for inclusion.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methods. Our primary outcomes were symptom improvement, recurrence, inactive cyst at 12 months and all-cause mortality at 30 days. Our secondary outcomes were development of secondary echinococcosis, complications of treatment and duration of hospital stay. We used GRADE to assess the certainty of evidence.

MAIN RESULTS

We included three RCTs with 180 adults and children with hepatic cystic echinococcosis. Two studies enrolled people aged 5 to 72 years, and one study enrolled children aged 6 to 14 years. One study compared standard catheterization plus albendazole with puncture, aspiration, injection and re-aspiration (PAIR) plus albendazole, and two studies compared laparoscopic surgery plus albendazole with open surgery plus albendazole. The three RCTs were published between 2020 and 2022 and conducted in India, Pakistan and Turkey. There were no other comparisons. Standard catheterization plus albendazole versus PAIR plus albendazole The cyst stages were CE1 and CE3a. The evidence is very uncertain about the effect of standard catheterization plus albendazole compared with PAIR plus albendazole on cyst recurrence (risk ratio (RR) 3.67, 95% confidence interval (CI) 0.16 to 84.66; 1 study, 38 participants; very low-certainty evidence). The evidence is very uncertain about the effects of standard catheterization plus albendazole on 30-day all-cause mortality and development of secondary echinococcosis compared to open surgery plus albendazole. There were no cases of mortality at 30 days or secondary echinococcosis (1 study, 38 participants; very low-certainty evidence). Major complications were reported by cyst and not by participant. Standard catheterization plus albendazole may increase major cyst complications compared with PAIR plus albendazole, but the evidence is very uncertain (RR 10.74, 95% CI 1.39 to 82.67; 1 study, 53 cysts; very low-certainty evidence). Standard catheterization plus albendazole may make little to no difference on minor complications compared with PAIR plus albendazole, but the evidence is very uncertain (RR 1.03, 95% CI 0.60 to 1.77; 1 study, 38 participants; very low-certainty evidence). Standard catheterization plus albendazole may increase the median duration of hospital stay compared with PAIR plus albendazole, but the evidence is very uncertain (4 (range 1 to 52) days versus 1 (range 1 to 15) days; 1 study, 38 participants; very low-certainty evidence). Symptom improvement and inactive cysts at 12 months were not reported. Laparoscopic surgery plus albendazole versus open surgery plus albendazole The cyst stages were CE1, CE2, CE3a and CE3b. The evidence is very uncertain about the effect of laparoscopic surgery plus albendazole on cyst recurrence in participants with CE2 and CE3b cysts compared to open surgery plus albendazole (RR 3.00, 95% CI 0.13 to 71.56; 1 study, 82 participants; very low-certainty evidence). The second study involving 60 participants with CE1, CE2 or CE3a cysts reported no recurrence in either group. The evidence is very uncertain about the effect of laparoscopic surgery plus albendazole on 30-day all-cause mortality in participants with CE1, CE2, CE3a or CE3b cysts compared to open surgery plus albendazole. There was no mortality in either group (2 studies, 142 participants; very low-certainty evidence). The evidence is very uncertain about the effect of laparoscopic surgery plus albendazole on major complications in participants with CE1, CE2, CE3a or CE3b cysts compared to open surgery plus albendazole (RR 0.50, 95% CI 0.13 to 1.92; 2 studies, 142 participants; very low-certainty evidence). Laparoscopic surgery plus albendazole may lead to slightly fewer minor complications in participants with CE1, CE2, CE3a or CE3b cysts compared to open surgery plus albendazole (RR 0.13, 95% CI 0.02 to 0.98; 2 studies, 142 participants; low-certainty evidence). Laparoscopic surgery plus albendazole may reduce the duration of hospital stay compared with open surgery plus albendazole (mean difference (MD) -1.90 days, 95% CI -2.99 to -0.82; 2 studies, 142 participants; low-certainty evidence). Symptom improvement, inactive cyst at 12 months and development of secondary echinococcosis were not reported.

AUTHORS' CONCLUSIONS

Percutaneous and surgical interventions combined with albendazole can be used to treat uncomplicated hepatic cystic echinococcosis; however, there is a scarcity of randomised evidence directly comparing these interventions. There is very low-certainty evidence to indicate that standard catheterization plus albendazole may lead to fewer cases of recurrence, more major complications and similar complication rates compared to PAIR plus albendazole in adults and children with CE1 and CE3a cysts. There is very low-certainty evidence to indicate that laparoscopic surgery plus albendazole may result in fewer cases of recurrence or fewer major complications compared to open surgery plus albendazole in adults and children with CE1, CE2, CE3a and CE3b cysts. Laparoscopic surgery plus albendazole may lead to slightly fewer minor complications. Firm conclusions cannot be drawn due to the limited number of studies, small sample size and lack of events for some outcomes.

A rare case of hepatic hydatid cyst in Somalia: a case report

Background

Echinococcosis, or hydatid disease, is caused by the larval forms of taeniid cestodes belonging to the genus Echinococcus. Echinococcus granulosus and E. multilocularis are the primary species responsible for human echinococcosis, and mostly they affect the liver. The disease course is typically slow, and the patients tend to remain asymptomatic for many years.

Case presentation

A case of 19-year-old male Somali from Medina, Saudi Arabia, was presented to the Mogadishu Somali Turkey Recep Tayyip Erdogan Training and Research Hospital with the complaint of right upper quadrant abdominal pain and dysuria for 1 month. A thorough physical examination, laboratory examination, and imaging investigations, including abdominal sonography and computed tomography (CT), were conducted.

Both ultrasound and CT scans revealed a cystic lesion in the right lobe of the liver, confirming the diagnosis of a hydatid cyst. Consequently, the patient underwent exploratory laparotomy. It was successfully managed surgically, and the definitive diagnosis was provided by the pathologist, confirming degenerated echinococcal cysts that contain abundant debris. Additionally, the patient received oral albendazole both before and after the surgery and after 7 months and is currently symptom-free.

Conclusions

Hydatid disease in the liver may persist without symptoms and often goes undiagnosed due to the slow growth of the cysts. The diagnosis needs careful history reporting, physical examination, and appropriate imaging investigations.

Evaluation of the Local and Peripheral Immune Responses in Patients with Cystic Echinococcosis

BACKGROUND

Cystic echinococcosis (CE) cysts may persist for decades because of immune modulation mechanisms. Here, we characterize the cysts and the blood immune responses in patients with CE.

METHODS

We enrolled 61 patients with CE and 19 control subjects. We received tissue samples from seven patients with CE and a control subject requiring liver cystectomy. The immunohistochemistry evaluation of the immune cell subtypes and cytokines in the pericysts and surrounding liver and the antigen B (AgB)-specific response analysis of whole blood were performed.

RESULTS

In CE, the pericyst and the surrounding liver parenchyma showed aggregates of CD3+ T lymphocytes, mainly CD4+. B lymphocyte aggregates were present in the liver tissue. Monocytes/granulocytes were rarely observed. Th2 cytokine expression was scarce, whereas IFN-γ expression was present in the CE tissues. The control subject did not show an inflammatory infiltrate. The IL-4-specific response to AgB was increased in the patients with CE compared to the control, and this result was confirmed in a larger cohort (p = 0.003), whereas the IFN-γ-response was similar between the two groups (p = 0.5570).

CONCLUSION

In patients with CE, CD4+ lymphocytes infiltrate the pericyst and the surrounding liver tissue with a low IL-4/IL-13 expression level and a moderate IFN-γ expression level; moreover, an IL-4 parasite-specific response is detected in the periphery. These results support adventitia involvement in CE immunopathogenesis.

Suitability of Fourier transform infrared microscopy for the diagnosis of cystic echinococcosis in human tissue sections

Cystic echinococcosis (CE) is a global health concern caused by cestodes, posing diagnostic challenges due to nonspecific symptoms and inconclusive radiographic results. Diagnosis relies on histopathological evaluation of affected tissue, demanding comprehensive tools. In this retrospective case study, Fourier transform infrared microscopy was explored for detecting and identifying CE through biochemical changes in human tissue sections. Tissue samples from 11 confirmed CE patients were analyzed. Archived FFPE blocks were cut and stained, and then CE-positive unstained sections were examined using Fourier transform infrared microscopy post-deparaffinization. Results revealed the method's ability to distinguish echinococcus elements from human tissue, irrespective of organ type. This research showcases the potential of mid-infrared microscopy as a valuable diagnostic tool for CE, offering promise in enhancing diagnostic precision in the face of the disease's complexities.

Cardiac cystic echinococcosis-A systematic review and analysis of the literature

Human cystic echinococcosis (CE) is a parasitic infection caused by the larval stage of the tapeworm Echinococcus granulosus sensu lato, primarily affecting the liver and lungs. Although the heart is affected in only 0.02-2% of all CE cases, a considerable number of cases have been, and continue to be, published. However, due to the rare occurrence of cardiac CE and the resulting lack of clinical trials, knowledge about various aspects of the disease remains limited. To obtain a clearer picture of anatomical, clinical, diagnostic as well as therapeutic aspects of cardiac CE, we systematically reviewed the literature published between 1965 and 2022. The anatomical pattern of the affected cardiac structures follows the extension of the supplying capillary bed. The majority of patients (82.7%) are symptomatic and present with prolonged non-specific symptoms such as dyspnoea, chest pain and palpitations. Acute complications generally derive from cyst rupture, occur in 18.3% of cases and manifest as embolism, pericardial tamponade, or anaphylactic reaction in 83.2%, 17.8% and 10.9% of these cases, respectively. As for CE cysts localized in other organs, the diagnosis of cardiac CE is made by imaging. Serology plays a minor role due to its limited sensitivity. Unlike abdominal CE cysts, cardiac CE cysts are usually resected independent of their stage (active/inactive), because their presence impairs cardiac performance and carries the risk of long-term sequelae. More than 80% of patients are treated with a single surgical intervention. We found a disease-related case fatality rate of 11.1%. Since local recurrence was reported up to 108 months and secondary CE up to 72 months after surgery, patients should be followed up for a minimum of 10 years.

Ultrasound diagnosis of cystic echinococcosis: updates and implications for clinical management

The diagnosis of cystic echinococcosis (CE) is based on imaging. Detection of a focal lesion with morphological characteristics of Echinococcus granulosus sensu lato metacestode is the starting point for the diagnostic workup. In organs explorable with ultrasound (US), this is the method of choice for both aetiological diagnosis of CE and staging of the CE cyst. Staging in terms of lesion morphology is also needed when serology is added to the diagnostic workflow when imaging alone is inconclusive. Finally, staging guides the clinical management of uncomplicated CE, especially in the liver. This commentary provides an overview of the most up-to-date evidence backing the above-mentioned role of US in the diagnosis and clinical management of CE. Finally, we outline future perspectives for the improvement of CE diagnosis.

Viability predictive factors of the daughter vesicles in hepatic cystic echinococcosis

INTRODUCTION

Management of cystic echinococcosis (CE) requires knowledge of certain aspects related to the survival of Echinococcus granulosus. The viability of daughter vesicles (DV) is a determining factor in guiding therapeutic indications, particularly for transiently active Cysts type CE3b.

PURPOSE

To determine the predictive factors of DV viability and its impact on the therapeutic management of CE3b type.

MATERIALS AND METHODS

This is a prospective pilot study with an analytical aim on patients with cystic echinococcosis of the liver type CE2 and CE3b, operated in the General Surgery Department of Habib-Bourguiba Academic Hospital, Sfax-Tunisia for 22 months from March 2018 until December 2019. The unit of the study is the DV. A parasitological study of the DV was done in the parasitology laboratory.

RESULTS

During the study period, 27 (40.9%) of 66 operated CE Disease from 21 patients containing 248 DV were explored. The median viability of DV protoscoleces was 16.7%. In bivariate analysis, factors for viability of DV protoscoleces were: fever, acute cholangitis, hyperbilirubinemia, left liver location, rock water and bilious echinococcal fluid (EF), cyst size ≥ 43 mm, Intracystic pressure ≥ 35 mmHg, DV size ≥ 6.5 mm, volume, number of DV/cyst ≥ 5, and opaque wall (p < 0.05). Predictive factors for the Non-viability of DV were: CE3b type, purulent EF, gelatinous EF. In multivariate analysis, only CE2 type, cyst size ≥ 43 mm, number of DV/cyst ≥ 5 and DV size ≥ 6.5 mm were factors significantly associated with the viability of DV protoscoleces.

CONCLUSION

CE3b cysts without the criteria of viability of DV protoscoleces may become candidates for the 'Wait-and-Watch' procedure.

Proton Nuclear Magnetic Resonance (1H NMR) Metabolomics Study in Serum, Urine, and Cystic Fluid for Differentiating Fertility and Staging of Intra-abdominal Hydatid Cyst in Adults

Background

Cystic echinococcosis (CE) is a parasitic zoonosis caused by the tapeworm Echinococcus granulosus. Over the past few years, a lot of research has been done on liver illnesses using metabolomics techniques to identify biomarkers which could identify the diseases in its early stages. The present study was done to explore biomarkers in serum, urine, and cystic fluid which would help in differentiating, staging, and assessing fertility of intra-abdominal hydatid cyst by using proton nuclear magnetic resonance (1H NMR) metabolomics.

Materials and methods

In the study, 28 subjects (16 cases and 12 controls) were enrolled. Staging of hydatid cysts was performed using ultrasonography. In patients complying with case and control definition, blood, urine, and cystic fluid were collected for complete blood count, urine culture, Echinococcus IgG enzyme-linked immunosorbent assay (ELISA), and metabolomic analysis. The 17, 15, and 11 metabolites in serum, urine, and cystic fluid samples were quantified, respectively, to differentiate between case and control group.

Results

In this study, we observed that there was a significant downregulation of succinate metabolite in urine samples of cases, down-regulation of five metabolites (isoleucine, valine, histidine, tyrosine and formate) and upregulation of alanine in cystic fluid of cases.

Conclusion

Current study demonstrates that metabolomics can be used non-invasively for rapid diagnosis of CE. This is one of the very few studies, which used 1H NMR spectroscopy, to analyze the profile of metabolites in serum, urine, and cystic fluid in cases of CE and controls.

How to cite this article

Raj N, Pandey A, Roy R, et al. Proton Nuclear Magnetic Resonance (1H NMR) Metabolomics Study in Serum, Urine, and Cystic Fluid for Differentiating Fertility and Staging of Intra-abdominal Hydatid Cyst in Adults. Euroasian J Hepato-Gastroenterol 2024;14(1):30-34.

Comparison of the Diagnostic Performance of Antigen B Purified from Sheep Hydatid Cyst Fluid (HCF) with Commercial ELISA Kit

INTRODUCTION

Cystic echinococcosis (CE) is a zoonotic parasitic disease caused by the metacestode of Echinococcus granulosus. CE is a health problem in Middle Eastern countries, such as Iran. The purpose of this study was to purify subunit 8 KDa antigen B from crude sheep hydatid cyst fluid (HCF) and compare its sensitivity and specificity with a commercial human ELISA kit (PT-Hydatid-96).

METHODS

28 sera samples were collected from hydatid cyst patients who had surgery for a hydatid cyst and had their disease confirmed by pathology after the surgery. Furthermore, 35 samples of healthy individuals with no history of hydatid cysts were collected, as were nine serum samples from parasite-infected non-CE patients. HCF was obtained from sheep fertile cysts at a Sari slaughterhouse and used as an antigen. In an indirect ELISA test, the B antigen was employed, and the results were compared to those from a commercial ELISA kit.

RESULTS

The results of this study were analyzed using the Kappa test. The commercial ELISA kit showed 17 cases (23.6%) positive, 44 cases (61.1%) negative, and 11 cases (15.3%) borderline. B antigen showed that 18 (25%), 43 (59.7 %), and 11 (15.3%) were positive, negative, and borderline, respectively. One sample (1.4% of 72 total samples) of 35 serum samples from healthy individuals was positive using B antigen-based ELISA. In addition, all nine serum samples from parasite-infected non-CE patients were negative for both tests. The sensitivity and specificity of the commercial ELISA kit have been evaluated at 60.7% and 100%, respectively. For B antigenbased ELISA, these values are 64.3 and 97.7%, respectively.

CONCLUSION

Antigen B produced from hydatid cyst fluid is a promising option for serological identification of hydatid cysts in both infected and healthy individuals. In an indirect ELISA test, hydatid fluid antigen could be used as a precise source of detection.

Hepatic macrophages play critical roles in the establishment and growth of hydatid cysts in the liver during Echinococcus granulosus sensu stricto infection

Cystic echinococcosis (CE) is a worldwide neglected zoonotic disease caused by infection with the larval stage of the tapeworm Echinococcus granulosus sensu lato (E. granulosus s.l.), which predominantly resides in the liver accompanied by mild inflammation. Macrophages constitute the main cellular component of the liver and play a central role in controlling the progression of inflammation and liver fibrosis. However, the role of hepatic macrophages in the establishment and growth of hydatid cysts in the liver during E. granulosus sensu stricto (E. granulosus s.s.) infection has not been fully elucidated. Here, we showed that CD68+ macrophages accumulated in pericystic areas of the liver and that the expression of CD163, a marker of anti-inflammatory macrophages, was more evident in active CE patients than in inactive CE patients. Moreover, in a mouse model of E. granulosus s.s. infection, the pool of hepatic macrophages expanded dramatically through the attraction of massive amounts of monocyte-derived macrophages (MoMFs) to the infection site. These infiltrating macrophages preferentially polarized toward an iNOS+ proinflammatory phenotype at the early stage and then toward a CD206+ anti-inflammatory phenotype at the late stage. Notably, the resident Kupffer cells (KCs) predominantly maintained an anti-inflammatory phenotype to favor persistent E. granulosus s.s. infection. In addition, depletion of hepatic macrophages promoted E. granulosus s.s. larval establishment and growth partially by inhibiting CD4+ T-cell recruitment and liver fibrosis. The above findings demonstrated that hepatic macrophages play a vital role in the progression of CE, contributing to a better understanding of the local inflammatory responses surrounding hydatid cysts and possibly facilitating the design of novel therapeutic approaches for CE.

'No cyst, no echinococcosis': a scoping review update on the diagnosis of cystic echinococcosis after the issue of the WHO-IWGE Expert Consensus and current perspectives

PURPOSE OF REVIEW

In 2010, the WHO-Informal Working Group on Echinococcosis (IWGE) published an Expert Consensus on the diagnosis and treatment of echinococcal infections. We provide an update on the diagnosis of cystic echinococcosis through a scoping review of the literature published after the release of the WHO-IWGE document.

RECENT FINDINGS

Ultrasound accurately and reliably depicts the pathognomonic signs of cystic echinococcosis (CE) stages compared with other imaging techniques. Among these, T2-wighted MRI is to be preferred to computed tomography, which has poor performance for the etiological diagnosis of CE. A negative serology cannot exclude the diagnosis of CE, while a positive serology, applied after the visualization of a CE-compatible lesion, may confirm a CE diagnosis. Serology alone must not be used to define 'CE' nor as 'screening' tool for infection. Other imaging and laboratory techniques did not show clinically applicable performances.

SUMMARY

In the absence of a focal lesion compatible with a CE cyst, no diagnosis of CE should be attempted. There is urgent need to achieve univocal CE case definitions and consensus diagnostic algorithm, as well as standardization of diagnostic methods and issue of a Target Product Profile of CE diagnostics, as advocated by the WHO in the 2021-2030 roadmap for neglected tropical diseases (NTDs).

IgG glycomic profiling identifies potential biomarkers for diagnosis of echinococcosis

Echinococcosis caused by larval stage of the genus Echinococcus, is a serious and potentially fatal parasitic zoonosis distributed globally. The two types of the disease in human are cystic echinococcosis (CE) and alveolar echinococcosis (AE). As the biological and encysting characteristics of the parasite, early diagnosis remains to address. In the present study, we demonstrate the value of Immunoglobulin G (IgG) glycome as a potential diagnostic biomarker for echinococcosis. Serum IgG glycome profiles were analyzed by ultra-performance liquid chromatography in a cohort comprised of 127 echinococcosis patients, of them 98 were diagnosed as CE and 29 as AE. IgG N-glycome analysis in pretreatment serum of echinococcosis patients presents 25 glycans and 64 derived traits. Compared with IgG glycans of healthy control group, neutral glycans, fucosylation and agalactosylated N-glycans increased while sialylation and galactosylation decreased in echinococcosis patients. Combined with a machine-learning-based approach, we built three biomarker combinations to distinguish CE, AE and healthy controls. Meanwhile, galactosylation, sialylation and A2BG2S1 in IgG glycan profiles were evidently associated with different types of CE (from CE1 to CE5). Our findings suggest that the alterations in IgG N-glycome may be of value in CE and AE diagnosis and follow-up CE disease progress. The role of IgG N-glycans as diagnostic biomarker remains to be verified in future study.

Metabolomic profiling of early inactive hepatic alveolar and cystic echinococcosis

Hepatic alveolar echinococcosis (AE) and cystic echinococcosis (CE) are severe helminthic zoonoses and leading causes of parasitic liver damage. They pose a high mortality risk due to invisible clinical signs, especially at the early inactive stage. However, the specific metabolic profiles induced by inactive AE and CE lesions remain largely unclear. Therefore, we used gas chromatography-mass spectrometry-based metabolomic profiling to identify the global metabolic variations in AE and CE patient sera to differentiate between the two diseases and reveal the mechanisms underlying their pathogenesis. In addition, specific serum biomarkers of inactive hepatic AE and CE were screened using receiver operating curves, which can contribute to the clinical diagnosis of both diseases, especially in the earlier phase. These differential metabolites are involved in glycine, serine, tyrosine, and phenylalanine metabolism. Further analysis of key metabolic pathways showed that inactive AE lesions strongly alter amino acid metabolism in the host. CE lesions have an altered metabolism of oxidative stress response. These changes suggest these metabolite-associated pathways can serve as biomarkers to distinguish individuals with inactive AE and CE from healthy populations. This study also investigated the differences in serum metabolic profiles in patients with CE and AE. The biomarkers identified belonged to different metabolic pathways, including lipid, carnitine, androgen, and bile acid metabolism. Taken together, by investigating the different phenotypes of CE and AE with metabolomic profiling, serum biomarkers facilitating early diagnosis were identified.

Cystic echinococcosis in northern Tanzania: a pilot study in Maasai livestock-keeping communities

Background

There are close similarities between the life-cycles of Echinococcus granulosus sensu lato (E. granulosus s.l.) that causes cystic echinococcosis (CE) in humans and Taenia multiceps/Coenurus cerebralis that causes cerebral coenurosis in small ruminants. Recent evidence highlights that livestock in Maasai communities of northern Tanzania are suffering from increases in the prevalence of cerebral coenurosis, leading to concerns about a possible concurrent increased risk of human CE. The aim of this study was to estimate the prevalence of human abdominal CE and the prevalence and species/genotypes of E. granulosus s.l. in livestock in Maasai communities.

Methods

Human CE was diagnosed by abdominal ultrasound on volunteers aged ≥ 7 years in five villages in the Longido and Ngorongoro Districts in northern Tanzania. Infection in ruminants was evaluated through inspection in local abattoirs, followed by molecular identification of one cyst per animal, with a priority for hepatic cysts, using PCR targeting of the cytochrome c oxidase I gene (COX1), followed by restriction fragment length polymorphism and multiplex PCR, and sequencing of non-E. granulosus s.l. samples.

Results

Ultrasound was performed on 823 volunteers (n = 352 in two villages in Longido District, and n = 471 in three villages of Ngorongoro). Hepatic CE cases were diagnosed only in Ngorongoro (n = 6; 1.3%), of which three had active cysts. Village-level prevalence of CE ranged between 0 and 2.4%. Of the 697 ruminants inspected, 34.4% had parasitic cysts. Molecular identification was achieved for 140 of the 219 (63.9%) cysts sampled. E. granulosus s.l. and T. hydatigena/Cysticercus tenuicollis were identified in 51.4% and 48.6%, respectively, of livestock cysts. E. granulosus s.l. was identified in livestock from both Longido (35.3% of 116 genotyped cysts) and Ngorongoro (91.2% of 34 genotyped cysts). Of the total of 72 E. granuslosus s.l. cysts identified in livestock, 87.5% were E. granulosus sensu stricto (G1–G3 genotypes), 9.7% were E. ortleppi (G5) and one cyst was E. canadensis (G6–10). The three active human cysts, which were removed surgically, were G1–G3 genotypes.

Conclusions

Multiple species/genotypes of E. granulosus s.l. are circulating in Maasai communities of northern Tanzania. Human CE was detected in villages of Ngorongoro District and a high prevalence of echinococcal cysts was observed in livestock in both districts. More precise estimation of the prevalence in this area and a better understanding of the specific risk factors for CE among Maasai communities in northern Tanzania is needed. Interventions targeting transmission routes common to both E. granulosus s.l. and T. multiceps would have dual benefits for preventing both human and livestock disease.

Graphical Abstract

Turkish HPB Surgery Association consensus report on hepatic cystic Echinococcosis (HCE)

OBJECTIVES

Cystic Echinococcosis (CE) is one of the important problems of the Eurasian region. We aimed to prepare a consensus report in order to update the treatment approaches of this disease. This study was conducted by Turkish HPB Surgery Association.

MATERIAL AND METHODS

This study was conducted with the modified Delphi model. For this purpose, we conducted a three-stage consensus-building approach.

RESULTS

Six topics, including diagnosis, medical treatment, percutaneous treatment, surgical treatment, management of complications and posttreatment follow-up and recurrences in HCE were discussed.

CONCLUSION

The expert panel made recommendations for every topic.

Ultrasound and contrast-enhanced ultrasound (CEUS) in infective liver lesions

Infektiöse fokale Leberläsionen (FLL) treten in der klinischen Praxis häufig auf, wobei bakterielle Leberabszesse die Hälfte ausmachen. Eine genaue Diagnose der FLL ist für die Auswahl der am besten geeigneten Therapie und zur Vorbeugung von Komplikationen unerlässlich. Ziel der aktuellen Arbeit ist es, den Nutzen von Ultraschall und kontrastmittelverstärktem Ultraschall (CEUS) zur Erkennung und Charakterisierung infektiöser Leberläsionen zu beschreiben.

Can parasite-derived microRNAs differentiate active and inactive cystic echinococcosis patients?

Cystic Echinococcosis (CE) is a neglected zoonotic disease caused by the metacestode form of Echinococcus granulosus sensu lato. Non-invasive imaging techniques, especially ultrasound, are primarily used for CE diagnosis. MicroRNAs (miRNAs) are small, non-coding RNA molecules that act as post-transcriptional regulators in various biological processes. After identification of parasite-derived miRNAs, these miRNAs are considered to be potential biomarkers for diagnosis and follow-up. The focus of this research is to compare the expression profiles of certain parasite-derived miRNAs in CE patients with active and inactive cysts as well as healthy controls. Parasite-derived miRNAs, egr-let-7-5p, egr-miR-71a-5p, and egr-miR-9-5p, of inactive CE patients were found to be differentially expressed with 3.74-, 2.72-, and 20.78-fold change (p < 0.05), respectively, when compared with active CE patients. In this study, we evaluated for the first time the expression profile of three parasite-derived miRNAs in the serum of CE patients to determine their potential to distinguish between active and inactive CE. It was concluded that serum levels of parasite-derived miRNAs, egr-let-7-5p and egr-miR-9-5p, could be promising new potential biomarkers for stage-specific diagnosis of CE. Further studies are needed with larger sample set to validate discriminating potential of these miRNAs.

Identification of infiltrating immune cell subsets and heterogeneous macrophages in the lesion microenvironment of hepatic cystic echinococcosis patients with different cyst viability

Human cystic echinococcosis (CE) is characterized by lesion microenvironment formation through gathering various immune cells, including macrophages. However, immune cell subsets and heterogeneous macrophages in CE lesion microenvironment are poorly defined. Massive infiltrating immune cells formed lesion microenvironment, among which CD4⁺T cells and CD19⁺B cells were predominant and CD68⁺ macrophages were more evident in patients with active cysts. Different degrees of liver fibrosis was observed in Peri-Lesion (PL) liver samples, which was more evident in patients with active cysts. Expression of both M1 and M2 macrophage markers was significantly increased in PL liver samples. Importantly, elevation of M1 macrophage markers was more obvious in patients with inactive cysts, whereas M2 macrophage markers represented dominant macrophage phenotype in patients with active cysts. Additionally, macrophage-derived MIF, TGF-β1 and ECM1 were also expressed at higher level in CE lesion microenvironment of patients with active cysts. Moreover, MIF was evidently enhanced in the serum of hepatic CE patients, which was also predominant in patients with active cysts. Correlation analysis demonstrated positive correlation between expression of macrophage-derived cytokines and liver fibrosis degree. Heterogeneous macrophages may play significant roles in liver fibrosis of CE lesion microenvironment through producing pro-fibrogenic cytokines.

Accuracy of an experimental whole-blood test for detecting reactivation of echinococcal cysts

BACKGROUND

Cystic echinococcosis (CE) is a complex disease for which clear understanding of clinical manifestations is needed to avoid misdiagnosis, inappropriate treatment, and severe complications. We evaluated the accuracy of a whole-blood stimulation test based on Interleukin (IL)-4 detection in response to Antigen B (AgB) of Echinococcus granulosus sensu lato to discriminate cyst viability and detect cyst reactivation in patients with hepatic CE.

METHODOLOGY/PRINCIPAL FINDINGS

Thirty patients with CE3b cysts and 37 patients with spontaneously-inactivated CE4-CE5 cysts were recruited (T0). After enrollment, 5 patients with CE3b cysts received albendazole, resulting in cyst solidification (CE4) in 4/5. Within a two-year follow-up, the whole-blood test was repeated at two time-points, in ≥14 (T1) and in ≥4 (T2) patients per group. IL-4 and a panel of other soluble factors were measured in the stimulated plasma. Baseline IL-4 levels were significantly higher in patients with CE3b compared to those with CE4 cysts (p = 0.006). Test accuracy for CE3b diagnosis had a sensitivity of 33-60% and a specificity of 76-95%, depending on the cut-off applied. Overall, IL-4 levels did not change significantly over time in either group; however, patients within the CE3b group showed a significant decrease of IL-1ra, IL-6, IL-8, G-CSF, IFN-γ, IP-10, MCP-1, MIP-1α, FGF at T1 compared to T0 (p≤0.042).

CONCLUSIONS/SIGNIFICANCE

Whole-blood IL-4-response to AgB is significantly higher in patients with active compared to inactive CE but apparently not modulated over time after treatment. On the contrary, the levels of IL-1ra, IL-6, IL-8, G-CSF, IFN-γ, IP-10, MCP-1, MIP-1α, FGF significantly decreased in active CE during follow-up. Additional studies are needed to understand whether these findings might have a clinical significance for patients' follow-up.

Field Performance of a Rapid Diagnostic Test for the Serodiagnosis of Abdominal Cystic Echinococcosis in the Peruvian Highlands

We evaluated the performance of a commercial rapid diagnostic test (RDT) in a field setting for the diagnosis of abdominal cystic echinococcosis (CE) using sera collected during an ultrasound population screening in a highly endemic region of the Peruvian Andes. Abdominal CE was investigated by ultrasonography. Sera collected from individuals with abdominal CE (cases) and age- and gender-matched volunteers with no abdominal CE (controls) were tested independently in two laboratories (Peru and Italy) using the VIRapid® HYDATIDOSIS RDT and RIDASCREEN® Echinococcus IgG enzyme-linked immunosorbent assay. Performance indexes of single and serially combined tests were calculated and applied to hypothetical screening and clinical scenarios. Test concordance was also evaluated. Prevalence of abdominal CE was 6.00% (33 of 546) by ultrasound. Serum was obtained from 33 cases and 81 controls. The VIRapid test showed similar sensitivity (76% versus 74%) and lower specificity (79% versus 96%) than results obtained in a hospital setting. RDTs showed better performance when excluding subjects reporting surgery for CE and if weak bands were considered negative. Concordance between tests was moderate to very good. In hypothetical screening scenarios, ultrasound alone or confirmed by RDTs provided more reliable prevalence figures than serology alone, which overestimated it by 5 to 20 times. In a simulation of case diagnosis with pre-test probability of CE of 50%, positive and negative post-test probabilities of the VIRapid test were 78% and 22%, respectively. The application of the VIRapid test alone would not be reliable for the assessment of population prevalence of CE, but could help clinical decision making in resource-limited settings.

Th1/Th2/Th17 cytokine profile in hepatic cystic Echinococcosis patients with different cyst stages

AIMS

The study aimed to investigate possible correlation between expression level of Th1/Th2/Th17-type profile and cyst viability in the systemic and local immunity of hepatic cystic Echinococcosis (CE) patients.

METHODS AND RESULTS

Expression of Th1-type interleukin (IL)-2, interferon (IFN)-γ, tumour necrosis factor (TNF)-α, Th2-type IL-4, IL-6, IL-10 and Th17-type IL-17A was examined in the serum and liver samples of hepatic CE patients with different cyst stages. Compared with healthy controls, Th1/Th2/Th17-type cytokines were significantly increased in the serum of hepatic CE patients. Moreover, expression of these cytokines was also at higher level in the inflammatory cell band of peri-lesion liver (PL) tissues than that in the adjacent normal (AN) liver tissues. Interestingly, elevation of Th1-type and Th17-type cytokines was more evident in PL tissues of patients with inactive cysts. Relatively, Th2-type cytokines were predominant in PL tissues of patients with active cysts.

CONCLUSION

Our findings provide new insights that Th1/Th2/Th2-type cytokine profile was associated with cyst stages. In hepatic CE patients with inactive cysts, Th1 and Th17-type cytokines were predominant. Comparatively, Th2-type cytokines were more evident in hepatic CE patients with active cysts, which may provide basis for the immune response diversity in hepatic CE patients with different cyst stages.

Promising proteins detected by Western blot from Echinococcus granulosus protoscoleces for predicting early post-surgical outcomes in CE-affected Tunisian children

BACKGROUND

Cystic echinococcosis (CE) affects predominantly young patients in highly endemic areas. Improved serological methods are needed for the follow-up of CE cases, especially given the high rates of post-surgical relapse that require detection as soon as possible.

METHODS

We designed a study to investigate the value of antigenic proteins extracted from Echinococcus granulosus (E. granulosus) protoscoleces, and of recombinant B2t and 2B2t proteins, for assessing the efficacy of surgical treatment carried out on CE-affected children. This study was performed on 278 plasma samples collected from 59 Tunisian children surgically treated for CE and monitored for 3 years post-surgery. The patients were classified according to post-surgical outcomes into a "non-relapsed" (NRCE) and a "relapsed" (RCE) group. We performed in-house ELISAs to measure anti-B2t and anti-2B2t IgG and immunoblotting for the detection of IgG against SDS-PAGE-resolved E. granulosus protoscoleces-specific antigens. The Wilcoxon test was applied to assess anti-B2t and anti-2B2t IgG levels. We applied the Cochran Q test to compare the distribution of immunoblotting antigenic bands between 1-month and 1-year post-surgery.

RESULTS

The probability of being "relapse-free" when a decrease in antibody titers occurred between 1 month and 1 year post-surgery was 81% and 75%, respectively, for anti-B2t and anti-2B2t IgG. We identified five protoscolex protein bands of 20, 26/27, 30, 40 and 46 kDa as highly immunoreactive by immunoblot for both RCE and NRCE patients at 1 month post-surgery, and significantly lower immunoreactivity after 1 year (p < 10^-4) for NRCE compared to RCE patients. The proteins at 26/27 and 40 kDa displayed the best performance in predicting the outcome, with an 84% probability of being relapse-free when the reactivity against the 40 kDa antigen, the doublet at 26/27 kDa, or both was absent or disappeared between 1 month and 1 year post-surgery, and a 93% probability of being relapsed when both bands remained reactive or increased in intensity between the two time points.

CONCLUSIONS

The B2t protein could be useful for the prediction of CE early post-surgical outcomes. The proteins of E. granulosus protoscoleces, especially the doublet P26/27 and P40, could be promising predictive biomarkers for the post-surgical follow-up of CE cases as well.

Soluble programmed death-1 (sPD-1) as predictor of early surgical outcomes of paediatric cystic echinococcosis

AIMS

Following treatment, cystic echinococcosis (CE) exhibits a relatively high relapse rate. Here, we evaluated the value of soluble programmed death-1 (sPD-1), sPD-1 ligand (sPD-L1) and anti-recP29 antibody concentrations, as predictors of early surgical treatment outcomes in young CE-affected patients.

METHODS AND RESULTS

This prospective study included 59 Tunisian children (177 plasmas), where CE was surgically treated and monitored for 3 post-operative years. Based on CE post-surgical development, patients were clustered into a 'No relapsed' CE (NRCE; n = 39) and a 'Relapsed' CE (RCE; n = 20) group. Plasma levels of sPD-1, sPD-L1 and anti-recP29 IgG were measured using ELISA. In the NRCE group, sPD-1, sPD-L1 and anti-recP29 IgG concentrations were significantly lower at D365 than at D30. By contrast, in the RCE group, no significant difference was observed between D0, D30 and D365. When considering individual variations, the probability to be 'relapse-free' was 67% and 73% when anti-recP29 IgG and sPD-L1 level, respectively, decreased between D30 and D365. The probability to be 'relapse-free' was 86% when the sPD-1 level decreased between D30 and D365 (P = .003; chi-square test).

CONCLUSION

sPD-1 may be a useful biomaker for the early evaluation of surgical procedure efficacy in paediatric CE cases.

Cystic Echinococcosis: Clinical, Immunological, and Biomolecular Evaluation of Patients from Sardinia (Italy)

Cystic echinococcosis (CE), a zoonotic disease caused by the larval stage of the tapeworm Echinococcus granulosus sensu lato (s.l.), is a worldwide public health problem. Echinococcus granulosus sensu stricto (s.s.), associated with G1 and G3 genotypes, is endemic with high prevalence in the Mediterranean basin. The parasite's life cycle comprises definitive hosts (canids) and intermediate hosts (ruminants) and can occasionally involve humans. The main aim of this research was to confirm the diagnosis of 13 patients suspected of CE who presented different complications and needed the surgical removal of the cysts. We also wanted to understand and clarify more the diagnosis of echinococcosis in humans. For this purpose, the patients first underwent cyst evaluation by ultrasound (US), immunological analysis, and then total pericystectomy, followed by parasitological, histopathological, and molecular biology examinations of the cysts. US stadiated one CE1, one CE2, eight CE3b, one CE4, and two CE5; immunology evidenced nine positives; histopathology confirmed 11 CE cysts, of which 8 fertile presenting protoscoleces were identified as E. granulosus s.s. by molecular biology, genotyped as three G1 and four G3 by neighbor-joining (NJ) phylogenetic tree. In conclusion, the results showed that 11 patients were affected by E. granulosus s.s. G1 orG3, and 2 cystic neoformations were of non-parasitic origin.

Proteomic analysis of plasma exosomes from Cystic Echinococcosis patients provides in vivo support for distinct immune response profiles in active vs inactive infection and suggests potential biomarkers

The reference diagnostic method of human abdominal Cystic Echinococcosis (CE) is imaging, particularly ultrasound, supported by serology when imaging is inconclusive. However, current diagnostic tools are neither optimal nor widely available. The availability of a test detecting circulating biomarkers would considerably improve CE diagnosis and cyst staging (active vs inactive), as well as treatments and follow-up of patients. Exosomes are extracellular vesicles involved in intercellular communication, including immune system responses, and are a recognized source of biomarkers. With the aim of identifying potential biomarkers, plasma pools from patients infected by active or inactive CE, as well as from control subjects, were processed to isolate exosomes for proteomic label-free quantitative analysis. Results were statistically processed and subjected to bioinformatics analysis to define distinct features associated with parasite viability. First, a few parasite proteins were identified that were specifically associated with either active or inactive CE, which represent potential biomarkers to be validated in further studies. Second, numerous identified proteins of human origin were common to active and inactive CE, confirming an overlap of several immune response pathways. However, a subset of human proteins specific to either active or inactive CE, and central in the respective protein-protein interaction networks, were identified. These include the Src family kinases Src and Lyn, and the immune-suppressive cytokine TGF-β in active CE, and Cdc42 in inactive CE. The Src and Lyn Kinases were confirmed as potential markers of active CE in totally independent plasma pools. In addition, insights were obtained on immune response profiles: largely consistent with previous evidence, our observations hint to a Th1/Th2/regulatory immune environment in patients with active CE and a Th1/inflammatory environment with a component of the wound healing response in the presence of inactive CE. Of note, our results were obtained for the first time from the analysis of samples obtained in vivo from a well-characterized, large cohort of human subjects.

Cerebral Cystic Echinococcosis

Cystic echinococcosis (CE) is a neglected helminthic disease and major public health problem in several regions of the world. The zoonosis is caused by the larval stage of different cestode species belonging to the genus Echinococcus. CE can affect any organ with the liver and lungs being most commonly involved. The brain is involved in less than 2% of the cases. We report a case of a CE1 echinococcal cyst of the brain in an Iranian patient.

Role of microRNAs in host defense against Echinococcus granulosus infection: a preliminary assessment

Cystic echinococcosis (CE) is a neglected helminthic zoonosis caused by the larval stage of the tapeworm Echinococcus granulosus s.l. MicroRNAs (miRNAs) are regulators of gene expression that have been linked with the pathogenesis of several human diseases, but little exists in the available literature about miRNAs in CE. Here, we investigate the expression profiles of 84 microRNAs relevant to the function of lymphocytes and other immune cells during CE infection in the peripheral blood of patients with cysts in active and inactive stages. We applied the microRNA PCR array technology to blood samples from 20 patients with a single hepatic CE cyst in either the active (CE3b) or inactive (CE4-CE5) stage. Our results show a significant upregulation of eight miRNAs (let-7g-5p, let-7a-5p, miR- 26a-5p, miR- 26b-5p, miR- 195-5p, miR- 16-5p, miR- 30c-5p, and miR- 223-3p) in patients with active cysts compared to those with inactive cysts. The high expression of these miRNAs in patients with active cysts suggests their role in a specific host immune response against the infection. Further work in this direction may help shed light on the pathogenesis of human CE.

In vitro metabolomic footprint of the Echinococcus multilocularis metacestode

Alveolar echinococcosis (AE) is a zoonotic disease that is deadly if left untreated. AE is caused by the larval metacestode stage of the cestode Echinococcus multilocularis. Better knowledge on the host-parasite interface could yield novel targets for improvement of the treatment against AE. We analyzed culture media incubated with in vitro grown E. multilocularis metacestodes by 1H nuclear magnetic resonance spectroscopy to identify the unknown metabolic footprint of the parasite. Moreover, we quantitatively analyzed all amino acids, acetate, glucose, lactate, and succinate in time-course experiments using liquid chromatography and enzymatic assays. The E. multilocularis metacestodes consumed glucose and, surprisingly, threonine and produced succinate, acetate, and alanine as major fermentation products. The metabolic composition of vesicle fluid (VF) from in vitro grown E. multilocularis metacestodes was different from parasite-incubated culture medium with respect to the abundance, but not the spectrum, of metabolites, and some metabolites, in particular amino acids, accumulated in the VF. Overall, this study presents the first characterization of the in vitro metabolic footprint of E. multilocularis metacestodes and VF composition, and it provides the basis for analyses of potentially targetable pathways for future drug development.

Sound Around the World: Ultrasound for Tropical Diseases

Ultrasound for diagnosis and staging of schistosomiasis and echinococcosis have paved the way over the past several decades for the application of ultrasound in tropical diseases. Until recently, the size and cost of ultrasound systems limited the application in low-resource settings. The increase in portable ultrasound systems has given more clinicians access to ultrasound, and clinically based protocols for the care of patients have emerged, such as focused assessment with sonography for HIV/TB and tropical cardiac ultrasound. This article explores the history and current use of ultrasound in these diseases and highlights their application in the care of patients.

Structural and Immunodiagnostic Characterization of Synthetic Antigen B Subunits From Echinococcus granulosus and Their Evaluation as Target Antigens for Cyst Viability Assessment

Background

Several tools have been proposed for serodiagnosis of cystic echinococcosis (CE), but none seems promising for cyst viability assessment. Antigens with stage-specific diagnostic value have been described, but few studies with well-characterized antigens and human serum samples have been performed. Antigen B (AgB) proteoforms hold promise as markers of viability, due to their differential stage-related expression and immunoreactivity.

Methods

Four AgB subunits (AgB1, AgB2, AgB3, AgB4) were synthesized and structurally characterized. Based on the preliminary evaluation of the subunits by western immunoblotting and enzyme-linked immunosorbent assay (ELISA), AgB1 and AgB2 were further tested in two ELISA setups and extensively validated on 422 human serum samples.

Results

All subunits showed a high degree of spontaneous oligomerization. Interacting residues within oligomers were identified, showing that both the N-terminal and C-terminal of each subunit are involved in homo-oligomer contact interfaces. No hetero-oligomer was identified. AgB1 and AgB2 ELISAs revealed different sensitivities relative to cyst stage. Of note, besides high specificity (97.2%), AgB1 revealed a higher sensitivity for active-transitional cysts (100% for CE1, 77.8% for CE2, 81.5% for CE3a, and 86.3% for CE3b) than for inactive cysts (41.7% for CE4 and 11.1% for CE5) and postsurgical patients (44%). Interestingly, 19 of 20 patients with spontaneously inactive cysts and 6 of 9 treated with albendazole >5 years earlier were negative on the AgB1 assay.

Conclusions

The structural characterization of subunits provides insights into the synthetic antigen conformation. The stage-related sensitivity of synthetic AgB1 holds promise as part of a multiantigen setting and deserves further longitudinal evaluation as marker of cyst viability.

[Cardiac manifestations of tropical diseases]

Due to an increase in global mobility, international travel and migration, tropical diseases are more frequently observed in Germany. Some tropical diseases can also affect the heart, cause cardiac symptoms and may require inclusion in differential diagnostic work-ups. The most important tropical diseases with cardiac involvement are Chagas' disease and echinococcosis. Other tropical diseases such as schistosomiasis, tropical endomyocardial fibrosis or sleeping sickness can affect the heart. The suspicion of a tropical disease as the cause of cardiac symptoms is based on the patient history of travel, migration and social setting. This CME article describes the diagnostic and therapeutic approach to tropical parasitic diseases with cardiac involvement.

Clinical management of cystic echinococcosis: state of the art and perspectives

PURPOSE OF REVIEW

This review draws attention to patients with cystic echinococcosis migrating from highly endemic to non-endemic countries with limited experience in cystic echinococcosis management, to ultrasound-based cyst staging, and to the WHO cyst classification as a powerful, to date underused tool to triage patients into the four currently available treatment modalities.

RECENT FINDINGS

In non- and low-prevalence countries, cystic echinococcosis is often misclassified. Differential diagnoses, such as simple cysts and other benign and malignant space-occupying lesions, have similar appearances on imaging. Serology is confirmatory but often disappointing due to sensitivity and specificity problems. There is increasing confidence in assigning uncomplicated cystic echinococcosis cysts to the four treatment modalities [drug treatment (benzimidazoles), percutaneous methods, surgery, watch and wait] on the basis of cyst stage (WHO cyst classification), size and location. However, current best practice is still not widely implemented outside cystic echinococcosis treatment centres, and further consolidation is needed by well-designed clinical trials. Recently published long-term follow-up studies have shown that patients with inactive cyst stages CE4 and CE5 benefit, especially since they do not need any treatment at all if they have not received prior benzimidazole or percutaneous therapy. Instead, cysts that have reached cyst stages CE4 and CE5 through drug treatment do need careful follow-up as they often relapse. Surgical procedures in which the cysts are opened and percutaneous approaches require very careful control of cyst content spillage to the peritoneum, pleura and intravascularly to prevent dissemination - a still too often neglected issue with severe consequences for patients.

SUMMARY

Though a neglected disease with predominantly expert-opinion-based treatment strategies, cystic echinococcosis patients can greatly benefit from interdisciplinary management in cystic echinococcosis treatment centres and cyst-stage-based assignment of treatment modalities. Increased suspicion for cystic echinococcosis in migrants from endemic to non-endemic countries is urgently needed at the current level of global mobility.

Severe chest allodynia as an unusual first presentation of hydatid disease: a case report

Background

Cystic echinococcosis (CE) is a worldwide zoonosis and the liver is the most commonly affected organ. Clinical manifestations range from completely asymptomatic cysts to a potential lethal cyst rupture and anaphylaxis.

Case presentation

Severe chest allodynia was an unusual clinical presentation of hepatic cyst rupture in the retroperitoneal space, without any other specific symptoms. CE diagnosis was confirmed by computed tomography scan and magnetic resonance. The patient underwent hepatectomy with complete resolution of the neuropathic pain.

Conclusions

Retroperitoneal hydatid cyst rupture is a rare event and its clinical manifestation may mimic other chest neuropathies.

Evaluation of the recombinant antigens B2t and 2B2t, compared with hydatid fluid, in IgG-ELISA and immunostrips for the diagnosis and follow up of CE patients

Cystic echinococcosis (CE) is one of the most widespread helminthic zoonoses and is caused by the tapeworm Echinococcus granulosus complex. CE diagnosis and monitoring primarily rely on imaging techniques, complemented by serology. This is usually approached by the detection of IgG antibodies against hydatid fluid (HF), but the use of this heterogeneous antigenic mixture results in a variable percentage of false positive and negative results, and has shown to be useless for follow-up due to the long persistence of anti-HF antibodies in cured patients. To improve test performances and standardization, a number of recombinant antigens mainly derived from HF have been described, among them the B2t and 2B2t antigens. The performance of these antigens in the diagnosis and follow up of patients with CE has been so far evaluated on a limited number of samples. Here, we evaluated the performances of tests based on B2t and 2B2t recombinant antigens compared to HF in IgG-ELISA and immunochromatography (IC) for the diagnosis and follow-up of patients with CE in a retrospective cohort study. A total of 721 serum samples were collected: 587 from 253 patients with CE diagnosed by ultrasonography (US), 42 from patients with alveolar echinococcosis and 92 from healthy donors from Salamanca (Spain). The highest overall sensitivity was obtained with HF in ELISA (85.5%), followed by IC containing HF and 2B2t-HF (83.0% and 78.2%, respectively). The lowest sensitivity was obtained with B2t and 2B2t in ELISA (51.8%). The highest specificity was obtained with IC containing 2B2t-HF (100%), and the lowest with HF-ELISA (78.0%). The lowest cross-reactivity with sera from patients with alveolar echinococcosis was detected with the recombinant antigens in ELISA (9.5% - 16.7%) and the highest with the HF-IC (64.3%). The results of B2t and 2B2t-ELISA were influenced by cyst stage, as classified by US according to the WHO-Informal Working Group on Echinococcosis (WHO-IWGE), with low sensitivity for inactive (CE4 and CE5) cysts, and by the drug treatment, with higher sensitivity in patients after drug treatment compared with patients not subjected to drug treatment. The two recombinant antigens in ELISA provided promising results for monitoring patients in follow-up, although their use is limited to patients with positive serology against them at the beginning of the follow-up. Potential biological reasons behind the low sensitivity of the recombinant antigens and possible strategies to enhance the performance of CE serology are discussed.

Cystic echinococcosis (CE) is a helminthic zoonosis caused by Echinococcus granulosus sensu lato. CE diagnosis and monitoring is of paramount importance for the clinical management of patients and primarily rely on imaging techniques, complemented by serology. CE serology is usually based on the detection of antibodies against hydatid fluid (HF), but the use of this heterogeneous antigenic mixture shows several drawbacks, including false positive and negative results, unsatisfied predictive values, and long persistence of detectable antibody levels in cured patients. As an alternative, to improve test performances and standardization, several recombinant antigens have been described, but these have been so far evaluated only on a limited number of samples. Here, two recombinant antigens derived from one of the immunodominant HF antigens (antigen B2) have been tested in enzyme-linked immunosorbent assay (ELISA) and in immunochromatographic strips (IC) against 721 serum samples. Although more specific than the HF, the recombinant antigens in ELISA showed low sensitivity for patients with inactive (CE4 and CE5) cysts and for patients not subjected to drug treatment. This limited their use for follow-up, although promising, to those patients with positive serology at the beginning of the follow-up period. These results will aid in the future development of a serological test with enhanced performance in the diagnosis and follow-up of patients with CE.

Ultrasound and Cystic Echinococcosis

The introduction of imaging techniques in clinical practice 40 years ago changed the clinical management of many diseases, including cystic echinococcosis (CE). For the first time cysts were clearly seen before surgery. Among the available imaging techniques, ultrasound (US) has unique properties that can be used to study and manage cystic echinococcosis. It is harmless, can image almost all organs and systems, can be repeated as often as required, is portable, requires no patient preparation, is relatively inexpensive and guides diagnosis, treatment and follow-up without radiation exposure and harm to the patient. US is the only imaging technique which can be used in field settings to assess CE prevalence because it can be run even on solar power or a small generator in remote field locations. Thanks to US classifications, the concept of stage-specific treatments was introduced and because US is repeatable, the scientific community has gained a clearer understanding of the natural history of the disease. This paper reviews the scope of US in CE, describes its strengths and weaknesses compared to other imaging techniques and its relationship with serodiagnosis and discusses sonographic features that may be helpful in differential diagnosis.

Watch and Wait Approach for Inactive Echinococcal Cyst of the Liver: An Update

Human cystic echinococcosis (CE) is a chronic, complex and neglected infection causing severe disease in humans. Hepatic CE cysts are detected and classified mainly by using ultrasound. Expert opinion and published data suggest that uncomplicated inactive liver cysts do not require treatment and only need to be monitored over time ("Watch and Wait"). Here we update our findings as published in 2014 on the "Watch and Wait" approach applied to inactive, asymptomatic cysts of the liver to keep the medical community informed. Clinical data of patients who accessed the World Health Organization Collaborating Center for CE at the University of Pavia-San Matteo Hospital Foundation from January 1991 to October 2017 were analyzed. Inclusion criteria were presence of one or more inactive uncomplicated cysts in the liver (CE4 or CE5), without any history of previous treatment, and an ultrasound-based follow-up of at least 24 months. Fifty-three patients with 66 inactive cysts fulfilled the inclusion criteria. Of these, 11 patients are newly described here; 37 were part of our previously described cohort and the follow-up for 17 of them was further extended; and five were excluded from the previously published analysis as their follow-up was too short, but could be included now. Without the need for treatment and without development of complications, 98.5% of cysts remained inactive over time. In only one patient (1.9% of patients), a reactivation of one cyst (1.5% of cysts) was observed.

Prevalence of abdominal cystic echinococcosis in rural Bulgaria, Romania, and Turkey: a cross-sectional, ultrasound-based, population study from the HERACLES project

BACKGROUND

Cystic echinococcosis is a neglected zoonotic infection that is distributed worldwide and prioritised by WHO for control efforts. The burden of human cystic echinococcosis is poorly understood in most endemic regions, including eastern Europe. We aimed to estimate the prevalence of abdominal cystic echinococcosis in rural areas of Bulgaria, Romania, and Turkey.

METHODS

We did a cross-sectional ultrasound-based survey that recruited volunteers from 50 villages in rural areas of Bulgaria, Romania, and Turkey. These villages were in provinces with annual hospital incidence of cystic echinococcosis within the mid-range for the respective countries. All people who attended a session were allowed to participate if they agreed to be screened. Abdominal ultrasound screening sessions were hosted in public community structures such as community halls, primary health-care centres, schools, and mosques. Lesions were classified using an adapted WHO classification. We reported the prevalence of abdominal cystic echinococcosis adjusted by sex and age through direct standardisation, using the country's rural population as a reference.

FINDINGS

From July 1, 2014, to Aug 3, 2015, 24 693 individuals presented to screening sessions and 24 687 underwent ultrasound screening. We excluded a further six indivduals due to missing data, leaving 24 681 people in our analysis. Abdominal cystic echinococcosis was detected in 31 of 8602 people screened in Bulgaria, 35 of 7461 screened in Romania, and 53 of 8618 screened in Turkey. The age and sex adjusted prevalence of abdominal cystic echinococcosis was 0·41% (95% CI 0·29-0·58) in Bulgaria, 0·41% (0·26-0·65) in Romania, and 0·59% (0·19-1·85) in Turkey. Active cysts were found in people of all ages, including children, and in all investigated provinces.

INTERPRETATION

Our results provide population-based estimates of the prevalence of abdominal cystic echinococcosis. These findings should be useful to support the planning of cost-effective interventions, supporting the WHO roadmap for cystic echinococcosis control.

FUNDING

European Union Seventh Framework Programme.

A T-cell diagnostic test for cystic echinococcosis based on Antigen B peptides

Cystic echinococcosis (CE) immunodiagnosis is still imperfect. We recently set-up a whole-blood test based on the interleukin (IL)-4 response to the native Antigen B (AgB) of Echinococcus granulosus. However, AgB is encoded by a multigene family coding for five putative subunits. Therefore, the aims of this study were to analyse the IL-4 response to peptides spanning the immunodominant regions of the five AgB subunits and to evaluate the accuracy of this assay for CE diagnosis. Peptides corresponding to each subunit were combined into five pools. A pool containing all peptides was also used (total pool). IL-4 evaluated by enzyme-linked immunosorbent assay was significantly higher in patients with CE compared to those without (NO-CE subjects) when whole-blood was stimulated with AgB1 and with the total pool. Moreover, IL-4 levels in response to the total pool were significantly increased in patients with active cysts. Receiver Operator Curve analysis identified a cut-off point of 0.59 pg/mL predicting active cysts diagnosis with 71% sensitivity and 82% specificity in serology-positive CE patients. These data, if confirmed in a larger cohort, offer the opportunity to develop new diagnostic tools for CE based on a standardized source of AgB as the peptides.

Immunology of cystic echinococcosis (hydatid disease)

BACKGROUND

The neglected disease cystic echinococcosis is caused by larval Echinococcus granulosus flatworms, which form bladder-like hydatid cysts in liver, lungs, and other organs.

SOURCES OF DATA

Published literature.

AREAS OF AGREEMENT

Establishing larvae are susceptible to antibody-dependent killing, as attested by successful animal vaccination, whereas once established they are partially protected by the so-called laminated layer. Host responses are Th2 dominated, with a Th1 component. Diagnostic antigens from cyst fluid are known, but responses appear absent in one-fifth of patients.

AREAS OF CONTROVERSY

Is evasion mainly based on induction of Th2 or regulatory responses by the parasite?

GROWING POINTS

The parasite induces regulatory responses. The laminated layer has immune-regulatory properties.

AREAS TIMELY FOR DEVELOPING RESEARCH

Develop tools for functional genomics; characterize immunologically interesting proteins suggested by genomic information; analyse infection in broader context of granulomatous responses; identify molecules secreted/excreted by intact larvae/cysts towards their outside, including diffusible immune-regulators.

Prevalence and Risk Factors for Human Cystic Echinococcosis in the Cusco Region of the Peruvian Highlands Diagnosed Using Focused Abdominal Ultrasound

AbstractLatin America is among the highly endemic regions for cystic echinococcosis (CE). In Peru, an estimated 1,139 disability-adjusted life years are lost annually from surgical treatment of CE. This is comparable with the combined total for Argentina, Brazil, Uruguay, and Chile. The prevalence of human infection has been investigated in the central Peruvian Andes, but there are no community-based screening data from other regions of Peru. We carried out a population survey in January 2015 using abdominal ultrasound to estimate the prevalence of abdominal CE in the Canas and Canchis provinces, in the Cusco region of Peru. Among 1,351 subjects screened, 41 (3%) had CE. There was significant variation between communities with similar socioeconomic features in a small geographical area. A history of CE was reported by 4.1% of the screened subjects, among whom 30.3% still had CE on ultrasound. Among patients reporting previous CE treatment, 14.9% had CE in active stages. Limited education, community of residence, and knowing people with CE in the community were associated with CE. These results demonstrate a significant burden of CE in the region and suggest the need for further investigations, control activities, and optimization of clinical management for CE in this area.