Innovation in hepatic alveolar echinococcosis imaging: best use of old tools, and necessary evaluation of new ones

Advances in Novel Diagnostic Techniques for Alveolar Echinococcosis

Alveolar echinococcosis (AE), caused by the larval stage of the tapeworm Echinococcus multilocularis, is a serious parasitic disease that presents significant health risks and challenges for both patients and healthcare systems. Accurate and timely diagnosis is essential for effective management and improved patient outcomes. This review summarizes the latest diagnostic methods for AE, focusing on serological tests and imaging techniques such as ultrasonography (US), computed tomography (CT), magnetic resonance imaging (MRI), and positron emission tomography/computed tomography (PET/CT). Each imaging modality has its strengths and limitations in detecting and characterizing AE lesions, such as their location, size, and invasiveness. US is often the first-line method due to its non-invasiveness and cost-effectiveness, but it may have limitations in assessing complex lesions. CT provides detailed anatomical information and is particularly useful for assessing bone involvement and calcification. MRI, with its excellent soft tissue contrast, is superior for delineating the extent of AE lesions and their relationship to adjacent structures. PET/CT combines functional and morphological imaging to provide insights into the metabolic activity of lesions, which is valuable for monitoring treatment response and detecting recurrence. Overall, this review emphasizes the importance of a multifaceted diagnostic approach that combines serological and imaging techniques for accurate and early AE diagnosis, which is crucial for effective management and improved patient outcomes.

EchiNam: multicenter retrospective study on the experience, challenges, and pitfalls in the diagnosis and treatment of alveolar echinococcosis in Belgium

OBJECTIVES

The aim of this retrospective study was to collect epidemiological, clinical, laboratory, imaging, management, and follow-up data on cases of alveolar echinococcosis (AE) diagnosed and/or followed up within the Namur Hospital Network (NHN) in order to gather information on the challenges, pitfalls, and overall experience in the diagnosis and treatment of AE.

METHODS

EchiNam was a multicenter retrospective study. Patients diagnosed and/or treated for probable or confirmed AE in the NHN between 2002 and 2023 were included in the study. Patient selection was based on diagnosis codes, laboratory results, and albendazole (ABZ) dispensing.

RESULTS

A total of 22 AE cases were retrieved, of which four were classified as probable and 18 as confirmed cases. Nine patients were either asymptomatic or had symptoms attributed to another disease. Clinical examination yielded pathologic findings in 10 patients. The median duration from the first AE-suggestive laboratory abnormalities to diagnosis was 176 days, and the median duration from the first AE-related imaging abnormalities to diagnosis was 133 days. Overall, 12 patients underwent surgical resection, with only four achieving complete lesion resection. Nine patients experienced ABZ-related adverse effects, with temporary ABZ discontinuation in five.

CONCLUSION

Due to various factors such as a long incubation period and a lack of awareness among Belgian physicians, AE is often diagnosed at advanced disease stages. Treatment then becomes more complex or even suboptimal, resulting in prolonged therapy, higher risk of adverse effects, significantly impaired quality of life, poor prognosis, and higher mortality rates. Measures should be taken to achieve early diagnosis in endemic areas.

Comparison of ultrasonographic features between two types of hepatic echinococcosis and hepatoblastoma in children

Introduction

The prevalence of hepatic alveolar echinococcosis (AE) and cystic echinococcosis (CE) is notably high among children in western China, with the mortality rate for untreated children potentially reaching up to 90%. Meanwhile, hepatoblastoma is the most common malignant liver tumor in children, yet its treatment differs significantly from that of hepatic echinococcosis. This study aimed to compare and analyze the ultrasonographic and contrast-enhanced ultrasound (CEUS) characteristics of hepatic CE, AE, and hepatoblastoma in children, providing more imaging evidence for accurate clinical diagnosis.

Methods

A retrospective analysis was conducted on preoperative data from children with pathologically confirmed hepatic echinococcosis in our hospital between 2012 and 2024. Furthermore, children consecutively diagnosed with hepatoblastoma between 2020 and 2024, confirmed by histopathological examination, were selected as the control group. Clinical data, conventional ultrasound images, and CEUS characteristics of hepatic echinococcosis and hepatoblastoma were analyzed and compared.

Results

The mean ages of 22 children with hepatic CE and nine children with hepatic AE were 11.6 ± 2.8 years and 11.8 ± 3.6 years, respectively. The mean age of 36 children with hepatoblastoma was 2.9 ± 3.0 years. Significant differences were observed in age and history of residence or travel to endemic areas among children with hepatic echinococcosis and hepatoblastoma (P < 0.001). Hepatic CE and hepatoblastoma showed a higher proportion of cystic degeneration [≥50% (54.5%, 12/22), and between 0% and <50% (47.2%, 17/36, respectively)], while hepatic AE predominantly showed no cystic degeneration (88.9%, 8/9). Clear boundaries were most commonly seen in hepatic CE lesions (95.5%, 21/22), while unclear boundaries were more frequent in hepatic AE lesions (88.9%, 8/9) (P < 0.05). Calcification was more prevalent in hepatic AE compared to hepatic CE and hepatoblastoma (P < 0.05). Hepatoblastoma exhibited richer color Doppler signals (94.4%, 34/36) compared to hepatic CE and AE (P < 0.05). CEUS was performed on two hepatic echinococcosis and nine hepatoblastoma lesions. On CEUS, one hepatic AE lesion showed peripheral hyperenhancement in the arterial phase, while one hepatic CE lesion showed no significant enhancement. In hepatoblastoma, nine lesions demonstrated hyperenhancement in the arterial phase and hypoenhancement in the late phase.

Conclusion

This study demonstrates the value of ultrasound in differentiating hepatic echinococcosis from hepatoblastoma in children. Hepatic CE typically manifests as a well-defined cystic or cystic-solid mass, while hepatic AE often presents as an ill-defined cystic-solid or solid mass with diffuse calcifications. Conversely, hepatoblastoma appears as a partially well-defined cystic-solid or solid mass with abundant color Doppler signals within and around the lesion.

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.

Pictorial review of hepatic echinococcosis: Ultrasound imaging and differential diagnosis

Echinococcosis is a zoonotic disease caused by parasites belonging to the genus Echinococcus that primarily affect the liver. The western plateau and pastoral areas of China are high-risk regions for hepatic cystic echinococcosis and hepatic alveolar echinococcosis (HAE). The high late mortality rate associated with HAE underscores the critical need for early diagnosis to improve cure rates and mitigate the disease burden in endemic areas. Currently, the World Health Organization recommends ultrasonography as the preferred initial screening method for hepatic echinococcosis. However, distinguishing between specific types of lesions, such as those of hepatic cystic echinococcosis and HAE, and other focal liver lesions is challenging. To address this issue, contrast-enhanced ultrasound is recommended as a tool to differentiate solid and cysto-solid hepatic echinococcosis from other focal liver lesions, significantly enhancing diagnostic accuracy. In this comprehensive review, we discuss the progression of hepatic echinococcosis and detail the imaging features of various types of echinococcosis using conventional, contrast-enhanced, and intraoperative ultrasound techniques. Our objective is to provide robust imaging evidence and guidance for early diagnosis, clinical decision making, and postoperative follow-up in regions with high disease prevalence.

Characteristics of the imaging diagnosis of alveolar echinococcosis

Alveolar echinococcosis (AE) primarily manifests in the liver and exhibits characteristics resembling those of slow-growing malignant tumours. Untreated Echinococcus multilocularis infection can be lethal. By infiltrating the vascular systems, biliary tracts, and the hilum of the liver, it might lead to various problems. Due to its ability to infiltrate neighbouring tissues or metastasize to distant organs, AE can often be mistaken for malignancies. We present a concise overview of the epidemiological and pathophysiological characteristics of AE, as well as the clinical manifestations of the disease. This article primarily examines the imaging characteristics of AE using various imaging techniques such as ultrasonography, computed tomography (CT), magnetic resonance imaging, diffusion-weighted imaging, and virtual non-enhanced dual-energy CT. We additionally examined the contribution of radiography in the diagnosis, treatment, and monitoring of the condition.

Chemotherapy for the treatment of alveolar echinococcosis: Where are we?

Alveolar echinococcosis (AE) is a severe liver disease due to infection with the Echinococcus multilocularis larval stage, called the metacestode. Management of AE is based on benzimidazole chemotherapy (albendazole or mebendazole), associated with surgery when possible. Benzimidazoles are the only compounds recommended for the treatment of AE; however, these are parasitostatic, which means that the parasite can resume growth when treatment is interrupted. Also, benzimidazoles can cause liver dysfunction which may prevent their use. Numerous drugs have been reported to have in vitro activity against E. multilocularis, but few had satisfactory in vivo activity, and none were clearly more effective than benzimidazoles. These drugs belong to various therapeutic categories including anti-infective agents (e.g. amphotericin B, mefloquine, pentamidine derivatives), anti-neoplastic compounds (e.g. imatinib, nilotinib, bortezomib), plant-extracted compounds (e.g. thymol, crocin, carvacrol) and others (e.g. metformin, verapamil, thiaclopride). These treatments are generally of limited interest due to their toxicity, their unfavorable pharmacokinetics, or the scarcity of studies involving humans. Apart from benzimidazoles, only amphotericin B, mefloquine and nitazoxanide have been reported to be used for human AE treatment, with unsatisfactory results. Few studies have aimed at developing innovative strategies for AE drug therapy, such as vectorization of drugs using nanoparticles. Altogether, this review emphasizes the urgent need for new therapeutic strategies in AE management, for which there is currently no curative chemotherapy.

A CT-based radiomics model for predicting lymph node metastasis in hepatic alveolar echinococcosis patients to support lymph node dissection

BACKGROUND

Hepatic alveolar echinococcosis (AE) is a severe zoonotic parasitic disease, and accurate preoperative prediction of lymph node (LN) metastasis in AE patients is crucial for disease management, but it remains an unresolved challenge. The aim of this study was to establish a radiomics model for the preoperative prediction of LN metastasis in hepatic AE patients.

METHODS

A total of 100 hepatic AE patients who underwent hepatectomy and hepatoduodenal ligament LN dissection at Qinghai Provincial People's Hospital between January 2016 and August 2023 were included in the study. The patients were randomly divided into a training set and a validation set at an 8:2 ratio. Radiomic features were extracted from three-dimensional images of the hepatoduodenal ligament LNs delineated on arterial phase computed tomography (CT) scans of hepatic AE patients. Least absolute shrinkage and selection operator (LASSO) regression was applied for data dimensionality reduction and feature selection. Multivariate logistic regression analysis was performed to develop a prediction model, and the predictive performance of the model was evaluated using receiver operating characteristic (ROC) curves, calibration curves, and decision curve analysis (DCA).

RESULTS

A total of 7 radiomics features associated with LN status were selected using LASSO regression. The classification performances of the training set and validation set were consistent, with area under the operating characteristic curve (AUC) values of 0.928 and 0.890, respectively. The model also demonstrated good stability in subsequent validation.

CONCLUSION

In this study, we established and evaluated a radiomics-based prediction model for LN metastasis in patients with hepatic AE using CT imaging. Our findings may provide a valuable reference for clinicians to determine the occurrence of LN metastasis in hepatic AE patients preoperatively, and help guide the implementation of individualized surgical plans to improve patient prognosis.

Clinical value of the semi-quantitative parameters of 18F-fluorodeoxyglucose PET/CT in the classification of hepatic echinococcosis in the Qinghai Tibetan area of China

BACKGROUND

To investigate the value of 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) semi-quantitative parameters, including the lesion diameter, maximum standardized uptake value (SUVmax), maximum standardized uptake value corrected for lean body mass (SULmax), metabolic lesion volume (MLV), and total lesion glycolysis (TLG), for classifying hepatic echinococcosis.

METHODS

In total, 20 patients with 36 hepatic echinococcosis lesions were included in the study. Overall, these lesions were categorized as hepatic cystic echinococcosis (HCE) or hepatic alveolar echinococcosis (HAE) according to the pathological results. Multiple semi-parameters including the maximum diameter, SUVmax, SULmax, MLV, and TLG were measured to classify HCE and HAE compared with the pathological results. The receiver operator characteristic curve and area under the curve (AUC) of each quantitative parameter were calculated. The Mann-Whitney U test was used to compare data between the two groups.

RESULTS

In total, 12 cystic lesions and 24 alveolar lesions were identified after surgery. There were significant differences in SUV max, SUL max, MLV, and TLG between the HAE and HCE groups (Z =  - 4.70, - 4.77, - 3.36, and - 4.23, respectively, all P < 0.05). There was no significant difference in the maximum lesion diameter between the two groups (Z =  - 0.77, P > 0.05). The best cutoffs of SUV max, SUL max, MLV, and TLG for the differential diagnosis of HAE and HCE were 2.09, 2.67, 27.12, and 18.79, respectively. The AUCs of the four parameters were 0.99, 0.99, 0.85, and 0.94, respectively. The sensitivities were 91.7%, 87.5%, 66.7%, and 85.6%, respectively, and the specificities were 90.1%, 91.7%, 83.3%, and 90.9%, respectively.

CONCLUSION

18F-FDG PET/CT semi-quantitative parameters had significant clinical value in the diagnosis and pathological classification of hepatic echinococcosis and evaluation of clinical treatment.

Giant Hydatid Cyst of the Liver Presenting With Severe Chest Pain and Deformity

Cystic echinococcosis (CE) is a parasitic disease caused by a larval stage (metacestode) of Echinococcus granulosus (E. granulosus), which is still endemic in many countries worldwide, despite the efforts of the World Health Organization (WHO) to reduce the disease burden in those countries. The hydatid cysts of the liver tend to grow gradually over a long period of time and may cause a variety of symptoms, either related to compression of adjacent organs or rupture. Here we report an unusual case of a giant hydatid cyst of the liver presenting to the emergency room (ER) of our hospital with chest deformity and severe chest pain, heralding impending rupture. Considering the very large size of the cyst (26×20 cm) and severe pain, we deemed expeditious surgery to be the best option. Upon surgery, the cyst contents were evacuated, biliary connections were ligated, and measures were taken to prevent the dissemination of the disease into the abdominal cavity. Closed drainage was used since the patient had almost no omentum. The patient received albendazole pre- and postoperatively. The patient was discharged in good condition after one week in the hospital.

Giant hydatid cyst of the liver: a case report with literature review

Hydatid cyst is a parasitic infection most commonly localized in the liver. They may not be diagnosed early because they remain asymptomatic at small sizes and may reach large sizes at the time of diagnosis. In this situation, compression symptoms may occur and they may present with serious complications such as rupture and anaphylactic shock, which are rare. Treatment methods are determined by classification according to the imaging techniques used in the diagnosis. In the present case, echinococcal cysts originating from segments 5, 6, and 7 in the right lobe of the liver, reaching 35 cm in diameter, caused compression symptoms. The diagnosis was made by abdominal tomography showing characteristic daughter vesicles and calcified cystic wall. The patient underwent pericystectomy and had an uneventful postoperative course with no recurrence in the 5-year follow-up.

LncRNA Regulation Mechanism in Hepatic Alveolar Echinococcosis with Nanosecond Pulse

BACKGROUND

The mortality of patients infected with hepatic alveolar echinococcosis (HAE) was higher. The aim of this study was to investigate the therapeutic effect of nanosecond pulsed electric fields (nsPEFs) on HAE in rats and explore the related molecular mechanisms.

METHODS

Establishment of HAE rat model and the lesions were treated with nsPEFs. The RNA of lesions in the high voltage nsPEFs treatment group and model group were extracted, and lncRNA and mRNA sequence analyses was performed. After obtaining the differentially expressed lncRNAs and mRNAs between the two groups, enrichment analysis was performed for mRNAs. The target genes of lncRNAs were predicted through co-location and co-expression. The expression of important lncRNAs and target genes in lesions was detected by qPCR.

RESULTS

The HAE rat model was successfully established. After nsPEFs treatment, the size of lesions was improved significantly. Then, we identified 270 differentially expressed lncRNAs and 1659 differentially expressed mRNAs between the high voltage nsPEFs treatment group and model group. Enrichment analysis showed that the differentially expressed mRNAs were mainly enriched in metabolism and inflammation. Five important lncRNAs regulatory networks were identified, then Cpa1, Cpb1, Cel, Cela2a, and Cela3b were identified as key target genes. Importantly, the expression of 5 lncRNAs and 5 target genes was verified in the lesions.

CONCLUSIONS

Preliminary results had shown that HAE treatment with nsPEFs can inhibit the growth of lesions. NsPEFs treatment altered gene expression in the lesions, and some genes were regulated by lncRNAs. The therapeutic mechanism may involve metabolism and inflammation.

Past and Present of Diagnosis of Echinococcosis: A Review (1999-2021)

The larval forms of taeniid cestodes belonging to the genus Echinococcus are the source of the zoonotic infection known as echinococcosis. Alveolar and cystic echinococcosis are caused by Echinococcus multilocularis and Echinococcus granulosus (s. s) respectively. It is endemic in several regions of the world. In this systematic review, we describe diagnosis, and the species (human, canids, livestock, and small rodents) affected by cystic (CE) and alveolar echinococcosis (AE). From 1999 to 2021, we searched the online directory through PubMed, SCOPUS, Web of Science, and google scholar. Among the 37,700 records found in the online databases, 187 publications met our eligibility requirements. The majority of investigations employed a range of diagnostic methods, such as ELISA, imaging, copro-PCR, necropsy or arecoline hydrobromide purgation, morphological cestode confirmation, and fecal sieving/flotation to detect and confirm Echinococcus infection. ELISA was the most commonly used method followed by PCR, and imaging. The research team retrieved data describing the incidence or assessment of the diagnostic test for E. multilocularis in humans (N = 99), canids (N = 63), small ruminants (N = 13), large ruminants (N= 3), camel (N= 2), pigs (N=2) and small mammals (N= 5). This study was conducted to explore the diagnostic tools applied to detect echinococcosis in humans as well as animals in prevalent countries, and to report the characteristic of new diagnostic tests for disease surveillance. This systematic review revealed that ELISA (alone or in combination) was the most common method used for disease diagnosis and diagnostic efficacy and prevalence rate increased when recombinant antigens were used. It is highly recommended to use combination protcols such as serological with molecular and imaging technique to diagnose disease. Our study identified scarcity of data of reporting echinococcosis in humans/ animals in low-income or developing countries particularly central Asian countries. Study reports in small rodents indicate their role in disease dissemination but real situation in these host is not refected due to limited number of studies. Even though echinococcosis affects both public health and the domestic animal sector, therefore, it is important to devise new and strengthe implementation of the existing monitoring, judging, and control measures in this estimate.

Differentiation of hepatic alveolar echinococcosis with a hemangioma-like pattern compared to typical liver hemangioma using contrast-enhanced ultrasound: a pilot study

PURPOSE

Echinococcus multilocularis infects humans as a false intermediate host, primarily with intrahepatic manifestation. Incorrect diagnostic interpretation of these liver tumors, especially the hemangioma-like pattern, can lead to progressive disease. The aim of the study was to investigate the differentiation of typical hemangioma and a hemangioma-like pattern of E. multilocularis using contrast-enhanced ultrasound (CEUS).

METHODS

This prospective clinical pilot study comprised patients with hemangioma (n = 14) and patients with alveolar echinococcosis (AE) and hemangioma-like pattern (n = 7). Inclusion criteria were the detection of a liver lesion according to a hemangioma-like pattern on E. multilocularis Ulm classification-ultrasound (EMUC-US) and "confirmed" or "probable" AE according to WHO case definition. The comparison group had hepatic hemangioma with typical B-scan sonographic morphology. All participants underwent conventional and contrast-enhanced ultrasonography.

RESULTS

The patient group comprised five men (71.4%) and two women (28.6%) with a mean average age of 64.1 ± 11.2 years. The patient group with hemangioma comprised nine female subjects (64.3%) and five male subjects (35.7%) with a mean average age of 56.1 ± 12.0 years. Early arterial bulbous ring enhancement (p < 0.0001) and iris diaphragm phenomenon could only be visualized in the patients with hemangioma (p < 0.0001). Furthermore, the patients with hemangioma exhibited hyperenhancement in the late phase (p = 0.0003). In contrast, the patients exhibited typical early arterial rim enhancement (p < 0.0001) and, in the portal venous and late phase, complete or incomplete non-enhancement (black hole sign; p = 0.0004).

CONSLUSION

The behavior of hemangioma-like AE lesions and typical liver hemangiomas is significantly different on CEUS. AE should be considered as a possible differential diagnosis, especially in high-endemic areas.

Multidetector computed tomography assessment of venous invasion in hepatic alveolar echinococcosis

PURPOSE

The objective of this study was to correlate multidetector computed tomography (MDCT) findings in hepatic alveolar echinococcosis (HAE) with intraoperative and postoperative histopathological results to identify reliable MDCT criteria for the diagnosis of HAE venous invasion.

METHODS

A total of 136 HAE patients who underwent CT examination were included in this study. The lesion-vessel contact angle, irregular wall, lumen stenosis and occlusion were evaluated.

RESULTS

A total of 614 veins were estimated. In total, 510 veins were invaded, and 104 veins were not. The invasion rate was 83.06%. In single CT findings, with a cutoff value of > 180° determined by receiver operating characteristic (ROC) curve analysis, the lesion-vessel contact angle performed the best (area under the ROC curve, AUC = 0.907, 95% confidence interval, 95% CI 0.872-0.941, p < 0.001), with a sensitivity, specificity and positive likelihood ratio (PLR) of 84.90%, 88.46%, and 7.35, respectively. Irregular wall and lumen stenosis showed the lowest diagnostic performance. Diagnostic performance was the highest when combining these criteria and signs (AUC = 0.932, 95% CI 0.905-0.960, p < 0.001).

CONCLUSION

The lesion-vessel contact angle > 180° had the best sensitivity and specificity in the diagnosis of HAE venous invasion, and good interobserver agreement had been noted. The diagnostic performance of the lesion-vessel contact angle > 180° had been further improved with the addition of lumen occlusion accompanied by irregular wall or lumen stenosis.

Evaluation of the Metabolic Activity of the Infiltration and Proliferation Areas of Hepatic Alveolar Echinococcosis in Rats Using Contrast-Enhanced Ultrasound

This study evaluated the value of contrast-enhanced ultrasound (CEUS) in assessing the metabolic activity of infiltration and proliferation areas of hepatic alveolar echinococcosis (HAE) in rats. CEUS was performed on Wistar rats with HAE. The average grayscale value of the HAE lesion in peripheral infiltration and proliferation areas (PIPAs) and the adjacent normal liver tissue was analyzed quantitatively. Contrast imaging was classified as highly increased enhancement, moderately increased enhancement, and equal or decreased enhancement. Microvessel density (MVD) in the PIPAs was classified as strongly positive, moderately positive, and weakly positive. The metabolic activity of HAE in the PIPAs was classified as high activity, moderate activity, and low activity according to the MVD classification results. The kappa test was combined with the metabolic activity level of the PIPAs to analyze the consistency of CEUS intensity and MVD. CEUS can score the metabolic activity of the infiltration and proliferation areas around HAE lesions, and provides a basis for clinical treatment and follow-up visits. CEUS could be used as a more economical and effective imaging option for evaluating the metabolic activity of HAE lesions.

Diagnostic and Management Perspectives in Alveolar Echinococcosis: Review of Literature

Alveolar echinococcosis is a life-threatening zoonotic disease caused by Echinococcus multilocularis. The disease usually primarily involves the liver and shows tumor-like growth. Early diagnosis of alveolar echinococcosis is difficult because the disease is usually asymptomatic in the early stages. Untreated cases are fatal and result in death within 10 years of liver involvement. In the diagnosis of alveolar echinococcosis, the patient's medical history, radiological imaging findings, and serological and histopathological tests are used together. Radiological imaging methods are very important for early diagnosis and differential diagnosis of the disease. In this article, we wanted to review the diagnosis and treatment of alveolar echinococcosis and emphasize the importance of keeping it in mind, especially in cystic lesions of the liver, and the importance of early diagnosis of the disease.

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.

Analysis of Ultrasonographic Characteristics of Early Hepatic Alveolar Echinococcosis

Objective

This study aims to investigate the ultrasonographic characteristics of early hepatic alveolar echinococcosis (HAE) and improve the qualitative diagnostic ability of sonographers.

Methods

The data of 80 positive cases of HAE screened and diagnosed by ultrasonography and serum immunology (33 males and 44 females with a mean age of 44.12 ± 14.31 y) were used in the study. The imaging characteristics of the lesions (i.e., intrahepatic distribution, shape, size, echo, blood flow, and growth characteristics) were analyzed retrospectively, and the ultrasonographic characteristics of early lesions were discussed in combination with their basic pathological changes.

Results

Patients with lesions of the proliferative infiltration type accounted for 57.5% (46/80), the fibrous calcification type accounted for 26.25% (21/80), the necrotic liquefaction type accounted for 6.25% (5/80), and the mixed type accounted for 10% (8/80). Patients with lesions involving the right lobe and the left lobe accounted for 76.25% (61/80) and 11.25% (9/80), respectively, and with lesions involving both the left and right lobes accounted for 12.5% (10/80). There were statistically significant differences in diameter between all types of lesions (n = 88; F = 5.926 and P = 0.004). Focal hyperechoic and diffuse heterogenous nodular changes were the main manifestations of early proliferative infiltration lesions.

Conclusion

Ultrasonography is extremely valuable in the diagnosis of early HAE. Capillary hemangioma-like changes and hailstorm sign are the main characteristics of early lesions of HAE, and calcification is a common concomitant sign.

Contrast-enhanced ultrasound (CEUS) in patients with metastasis-like hepatic alveolar echinococcosis: a cohort study

PURPOSE

Hepatic alveolar echinococcosis (HAE) of the metastasis-like pattern, according to the Echinococcus Ulm classification, is usually discovered as an incidental finding, and the diagnostic differentiation from "true metastases" is difficult. The aim of this study was to investigate whether lesions of the "metastasis-like pattern" in HAE show a typical contrast behavior that can be used for differentiation from metastasis in malignancies.

METHODS

This prospective clinical study included 11 patients with histologically confirmed HAE of the metastasis-like pattern (7 female and 4 male; mean age, 57.1 years; mean disease duration, 59.5 months), who had been examined by B-scan sonography and CEUS, from the National Echinococcosis Registry Germany.

RESULTS

On contrast-enhanced sonography, 11/11 reference lesions showed annular rim enhancement in the arterial and portal venous phases. Throughout the entire 4-min study period, none of the reference lesions showed central contrast enhancement-i.e., all exhibited a complete "black hole sign". A small central scar was seen in 81.8% of cases.

CONCLUSION

In clinically unremarkable patients with incidentally detected metastasis-like lesions of the liver, contrast-enhanced sonographic detection of rim enhancement without central contrast uptake (black hole sign) should be considered evidence supporting a diagnosis of hepatic alveolar echinococcosis with a rare metastasis-like pattern. This can help to differentiate HAE from metastases, especially in high-endemic areas.

Role of the radiologist in the diagnosis and management of the two forms of hepatic echinococcosis

Echinococcosis is a parasitic disease caused by two zoonotic tapeworms (cestodes) of the Echinocococcus genus. It can be classified as either alveolar or cystic echinococcosis. Although the two forms differ significantly in terms of imaging findings, they share similarities in terms of management and treatment. In parallel to medical treatment with albendazole (ABZ), and surgery, historically used in these diseases, various imaging-guided interventional procedures have recently emerged (drainage, stenting, or Puncture, aspiration, injection, and reaspiration (PAIR)). These options open up a new range of therapeutic options. As in oncology, multidisciplinary consultation meetings now play a major role in adapted management and patient care in hepatic echinococcosis. Consequently, diagnostic imaging and interventional expertise have brought radiologists to the fore as important members of these multidisciplinary team. The radiologist will need to evaluate parasite activity in both forms of the disease, to guide the choice of the appropriate therapy from among medical treatment, interventional radiology procedures and/or surgical treatment. Knowledge of the specific complications of the two forms of echinococcosis will also help radiologists to discuss the appropriate treatment and management. The aim of this review is to describe the core knowledge that what a radiologist should possess to actively participate in multidisciplinary meetings about hepatic echinococcosis. We discuss the role of imaging, from diagnosis to treatment, in alveolar (AE) and cystic echinococcosis (CE), respectively.

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.

Imaging Aspects of Hepatic Alveolar Echinococcosis: Retrospective Findings of a Surgical Center in Turkey

Radiologists should be aware of the findings of alveolar echinococcosis (AE) due to the diagnostic and management value of imaging. We are attempting to define the most common diagnostic imaging findings of liver AE, along with the prevalence and distribution of those findings. The patients' US, CT, and MRI images were reviewed retrospectively. CT images were acquired with and without the administration of contrast medium. The MRI protocol includes T2-weighted images (WI), diffusion (WI), apparent diffusion coefficient (ADC) maps, and pre- and post-contrast T1WIs. The current study included 61 patients. The mean age of the population was 58.2 ± 9.6 years According to Kratzer's categorization (US), 139 lesions (73.1%) were categorized as hailstorm. According to Graeter's classification (CT), 139 (73.1%) lesions were type 1-diffuse infiltrating. The most frequent types were Kodama type 2 and 3 lesions (MRI) (42.6% and 48.7%, accordingly). P2N0M0 was the most frequent subtype. The current study defines the major, characteristic imaging findings of liver AE using US, CT, and MRI. Since US, CT, and MRI have all been utilized to diagnose AE, we believe that a multi-modality classification system is needed. The study's findings may aid radiologists in accurately and timely diagnosing liver AE.

Evaluation of Eosinophilic Cationic Protein as a Marker of Alveolar and Cystic Echinococcosis

Echinococcosis is a neglected zoonotic disease and a worldwide public health problem caused by infection with the larval stages of taeniid cestodes of the genus Echinococcus. In vitro studies have demonstrated a protoscolecidal effect of eosinophilic cationic protein (ECP), a granule protein of eosinophilic granulocytes, against E. granulosus. Therefore, the main objective of this study was to evaluate ECP as a biomarker in the treatment of alveolar echinococcosis (AE) and cystic echinococcosis (CE). Data were collected retrospectively from the Vienna Echinococcosis Cohort over 7 years until December 2020. Altogether, 32 patients (16 AE and 16 CE) were included. In the selected patients, serum ECP values were compared before and after the beginning of an operative and/or benzimidazole (BMZ) therapy. Mean ECP serum levels before intervention were significantly (p < 0.05) elevated at 34.0 ± 22.9 μg/L in AE patients and at 38.6 ± 19.9 μg/L in CE patients compared to the control group. After the intervention, mean ECP levels decreased significantly (p < 0.05) to 20.4 ± 14.6 μg/L in AE patients and to 22.4 ± 8.3 μg/L in CE patients. Furthermore, ECP showed a significant (p < 0.05) correlation of k = 0.56 with PET–CTI. Based on the significant decrease after operative and/or BMZ treatment and the correlation with clinical markers such as PET–CTI, it is recommended to investigate ECP more intensively as a marker of AE and CE in prospective studies with larger cohorts.

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.

Stage-Oriented CT Classification and Intermodal Evolution Model in Hepatic Alveolar Echinococcosis

Background

Alveolar echinococcosis (AE) is one of the most dangerous human parasitoses. The main site of disease manifestation is the liver (about 98 %). The Echinococcus Multilocularis Ulm Classification for Computed Tomography (EMUC-CT), presented in 2016, was the first compilation of CT morphological criteria of hepatic AE. Studies based on EMUC-CT made it possible to draw conclusions about the development of the lesions in the course of disease beyond purely diagnostic typing. Among the most important findings of these precursor studies was that EMUC-CT type IV presented as an initial lesion, whereas EMUC-CT type III lesions were mostly associated with an advanced disease constellation. An intermodal view of image morphological criteria provides further multi-layered indications for lesion evolution.

Method

With the “Alveolar Echinococcosis Ulm Classification” (AEUC), a revision of the previous EMUC-CT was carried out with stage-oriented reorganization of the primary morphologies. Furthermore, an intermodal classification scheme for the evolution of hepatic AE lesions based on AEUC, MRI Kodama classification, and aspects of ultrasound could be outlined.

Results

The first stage-oriented CT classification of hepatic AE “AEUC” is based with respect to its lesion characterization on the separate consideration of two classification pillars, the five “primary morphologies”, AEUC I–V (AEUC II–IV with subcriteria) and the five “patterns of calcification”. In addition, an intermodal classification scheme presents five stages of lesion evolution: “initial stage”, “progressive stage”, “advanced stage”, “transitional stage” and “regressive stage”.

Conclusion

The imaging modalities differ with respect to their visualization of lesion criteria. This underlines the need for unimodal classification systems. Staging of an AE lesion can be done more accurately by evaluating different modalities.

Key Points:

Citation Format

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.

Triphase contrast-enhanced CT to evaluate indications for autologous liver transplantation in patients with end-stage hepatic alveolar echinococcosis

Autologous liver transplantation (ALT) to cure end-stage hepatic alveolar echinococcosis (HAE) requires that hepatobiliary surgeons understand the invasion of intrahepatic structure and adjacent tissues or organs. Triphase contrast-enhanced CT of the liver has been widely used for diagnosis and preoperative evaluation of HAE. Three-dimensional (3D) reconstruction allows for accurate measurement of remnant liver volume (RLV). The objective of the study was to evaluate value of triphase contrast-enhanced CT together with 3D reconstruction in preoperative evaluation of indications for ALT in patients with end-stage HAE. This cohort include twenty-one consecutive patients with end-stage HAE, who preoperatively underwent triphase enhanced CT together with 3D reconstruction for ALT. To depict the indications, the 2D image data were reviewed statistically focusing on porta hepatis invasion, retrohepatic vena cava (RHVC) involvement and degrees of intrahepatic vessel invasion, and the 3D reconstruction was performed to obtain ratio of RLV to standard liver volume (SLV). The results showed that 95.24% patients (20/21) had porta hepatis invasion. When lesions located in right liver lobe, porta hepatis invasion occurred most commonly in the second and third porta hepatis (7/10), whereas the first, second and third porta hepatis were most commonly invaded by lesions in the right and caudate / left medial liver lobes (7/11) (P < 0.05). The mean value of longitudinal invasion of RHVC was 8.0 cm, and 95.2% (20/21) of patients had RHVC invasion with ≥ 180° circumferential invasion. As for the important vascular events, moderate and severe invasion occurred most commonly in the right hepatic vein, right branch of portal vein and RHVC each in 95.2% (20/21) patients (P < 0.05). We also found that preoperative CT had a good agreement with intraoperative findings in assessing intrahepatic vascular involvement by HAE (kappa index = 0.77). The estimated average ratio of RLV to SLV was 0.95 (range, 0.43-1.62). In conclusion, the 2D contrast-enhanced CT could well depict anatomic location and size of HAE, and invasion of porta hepatis and vascular by this disease, and involvement of other adjacent organs and tissues. Above all, 3D reconstruction could accurately measure RLV in patients with end-stage HAE for ALT.

Long-term follow-up of liver alveolar echinococcosis using echinococcosis multilocularis ultrasound classification

BACKGROUND

When Echinococcus multilocularis infects humans as a false intermediate host, alveolar echinococcosis (AE) usually manifests primarily intrahepatically and is initially asymptomatic. If the disease remains undiagnosed and untreated, progressive growth occurs, reminiscent of malignant tumours. The only curative therapy is complete resection, which is limited to localised stages, and palliative drug therapy is used otherwise. Consequently, early diagnosis and reliable detection of AE lesions are important. For this reason, abdominal ultrasonography, as the most common primary imaging for AE, relies on classification systems.

AIM

To investigate how hepatic AE lesion sonomorphology changes over time in the Echinococcosis Multilocularis Ulm Classification (EMUC)-ultrasound (US) classification.

METHODS

Based on data from Germany’s national echinococcosis database, we evaluated clinical and US imaging data for 59 patients according to the AE case definition in our preliminary retrospective longitudinal study. There had to be at least two liver sonographies ≥ 6 mo apart, ≥ 1 hepatic AE lesion, and complete documentation in all US examinations. The minimum interval between two separately evaluated US examinations was 4 wk. The AE reference lesion was the largest hepatic AE lesion at the time of the first US examination. To classify the sonomorphologic pattern, we used EMUC-US. In addition to classifying the findings of the original US examiner, all reference lesions at each examination time point were assigned EMUC-US patterns in a blinded fashion by two investigators experienced in US diagnosis. Statistical analysis was performed using SAS version 9.4 (SAS Institute Inc., Cary, NC, United Stated). P values < 0.05 were considered statistically significant.

RESULTS

The preliminary study included 59 patients, 38 (64.5%) women and 21 (35.6%) men. The mean age at initial diagnosis was 59.9 ± 16.9 years. At the time of initial ultrasonography, a hailstorm pattern was present in 42.4% (25/59) of cases, a hemangioma-like pattern in 16.9% (10/59), a pseudocystic pattern in 15.3% (9/59), and a metastasis-like pattern in 25.4% (15/59). For the hailstorm pattern, the average lesion size was 67.4 ± 26.3 mm. The average lesion size was 113.7 ± 40.8 mm with the pseudocystic pattern and 83.5 ± 27.3 mm with the hemangioma-like pattern. An average lesion size of 21.7 ± 11.0 mm was determined for the metastasis-like pattern. Although the sonomorphologic pattern remained unchanged in 84.7% (50/59) of AE reference lesions, 15.3% (9/59) showed a change over time. A change in pattern was seen exclusively for AE lesions initially classified as hemangioma-like or pseudocystic. A total of 70% (7/10) of AE lesions initially classified as hemangioma-like showed a relevant change in pattern over time, and 85.7% (6/7) of these were secondarily classified as having a hailstorm pattern, with the remainder (1/7; 14.3%) classified as having a pseudocystic pattern. A total of 22.2% (2/9) of AE lesions initially classified as pseudocystic showed a relevant change in pattern over time and were classified as having a hailstorm pattern. For AE lesions initially classified as having a hailstorm or metastatic pattern, no pattern change was evident. All patients with pattern change were on continuous drug therapy with albendazole.

CONCLUSION

The sonomorphology of hepatic AE lesions may change over time. The hemangioma-like and pseudocystic patterns are affected.

Kodama-XUUB: an informative classification for alveolar echinococcosis hepatic lesions on magnetic resonance imaging

Objective: To propose a modification of the Kodama classification to classify type III lesions of alveolar echinococcosis (AE) that do not have microcysts. Materials and Methods: 200 magnetic resonance imaging (MRI) images of AE liver lesions from four endemic regions of the world were classified according to Kodama, distinguishing within type III those with microcysts from those without. Each center included 50 MRIs of patients with unoperated AA liver lesions. The first 50 cases were classified by a first reader in the presence of four second-line readers from each region. Then each second-line reader classified his or her 50 cases. Results: In all centers, type III lesions were predominant: 58% of the total lesions and 23% of them were without microcysts. The average age of the patients was 47 years. In China, the patients were on average younger and the lesions larger. German patients had more lesions within the liver. Type I and II lesions, synonymous with earlier diagnosis, were more common in Europe. Conclusion: The Kodama classification needed to be modified because of the existence of a significant proportion of unclassifiable lesions. This is especially true since the presence of microcysts is an informative element of parasite activity. Therefore, this study proposes a Kodama-XUUB classification with type IIIa lesions having microcysts and type IIIb lesions not having microcysts.

Recent advances in ultrasound in the diagnosis and evaluation of the activity of hepatic alveolar echinococcosis

Echinococcosis is a worldwide neglected zoonotic disease. Alveolar echinococcosis (AE) poses a more serious threat to life and health than cystic echinococcosis, and has been one of the world's most lethal chronic parasitosis. Assessment of metacestode activity status is essential for individual treatment strategy design for a given AE patient, and fluorodeoxyglucose positron-emission tomography (FDG-PET) has been the gold standard. In this study, we reviewed previous evidence on AE activity assessment using contrast-enhanced ultrasound (CEUS), and its comparison with FDG-PET. The results showed good consistency between them, indicating CEUS as a suitable substitute for FDG-PET. With its advantage as being readily portable, widely available, and not costly, CEUS is more suitable for use in the developing countries and rural areas.

Hepatic Alveolar Echinococcosis

Hepatic alveolar echinococcosis (HAE) is a rare but severe zoonosis caused by the pseudotumoral intrahepatic development of the larval stage of the tapeworm Echinococcus multilocularis. HAE is present only in the Northern Hemisphere, predominantly in China. Currently, there is a significant resurgence of cases in historically endemic areas associated with emergence of HAE in countries not previously concerned. Today, in European countries, HAE is often discovered by chance; however, clinicians should be made aware of opportunistic infections that progressively emerged recently as a result of therapeutic or pathological immunosuppression. Ultrasonography is the key first-line diagnostic procedure, with specific serology providing confirmation in 95% of the cases. Albendazole, only parasitostatic, is the mainstay for treatment. Surgical resection, if feasible, is the gold standard for treatment, and more patients are currently eligible for this option because of an earlier diagnosis. The prognosis has considerably improved but remains poor in countries where access to care is less favorable.

A Case of Human Hepatic Alveolar Echinococcosis Accompanied by Lung and Brain Metastases

Alveolar echinococcosis (AE) is considered as a fatal zoonosis caused by the larvae of Echinococcus multilocularis. The lungs and brain are the most common metastatic organs. We report a human case of hepatic alveolar echinococcosis accompanied by lung and brain metastasis. In particular, the patient had a history of tuberculosis and the lung lesions were easily misdiagnosed as lung abscesses. The lesions of liver and lung underwent radical resection and confirmed as alveolar echinococcosis by pathological examination. The patient had no surgical complications after operation and was discharged after symptomatic treatment. Unfortunately, the patient later developed multiple intracerebral AE metastases. We required the patient to take albendazole orally for life and follow up.

PET/CT helps to determine treatment duration in patients with resected as well as inoperable alveolar echinococcosis

PURPOSE

The aim of the study was to determine the role of ¹⁸F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) at the end of benzimidazole therapy in alveolar echinococcosis.

METHODS

A total of 22 patients undergoing PET/CT at the end of benzimidazole therapy were retrospectively registered. Maximum standardized uptake values (SUV_max) were measured in remaining echinococcus manifestations and compared to normal liver tissue. Long-term clinical follow-up was performed, and recorded data included laboratory parameters, clinical information and imaging.

RESULTS

All patients had no detectable levels of Em-18 antibodies and all echinococcus manifestations were negative on PET/CT, i.e. without focally increased FDG uptake or uptake higher than normal/non-infected liver tissue. All manifestations displayed significantly less FDG-uptake than normal liver tissue, i.e. SUVmax 1.8 (interquartile range (IQR) 1.5-3.5) vs. 3.0 (IQR 2.6-5.7), (p < 0.001). Patients were clinically followed for a median of 9.5 years (IQR 6.5-32.0 years) after their initial diagnosis and for 4.5 years (IQR 3.0-14.0 years) after discontinuation of benzimidazole therapy. No patient showed signs of recurrent infection at the last clinical visit. The 10-year and 20-year freedom from all-cause mortality was 95.0% (95% confidence interval 69.5% - 99.3%), for both. Two events occurred in 292 patient years of follow-up; i.e. two patients (9%) died, one because of pancreatic cancer, the other one because of unknown reasons with no detectable antibody levels.

CONCLUSIONS

Negative FDG-PET/CT results combined with no detectable levels of Em-18 antibodies may allow for the safe discontinuation of benzimidazole therapy in patients with alveolar echinococcosis.

Hepatic Alveolar Echinococcosis: Predictive Biological Activity Based on Radiomics of MRI

BACKGROUND

To evaluate the role of radiomics based on magnetic resonance imaging (MRI) in the biological activity of hepatic alveolar echinococcosis (HAE).

METHODS

In this study, 90 active and 46 inactive cases of HAE patients were analyzed retrospectively. All the subjects underwent MRI and positron emission tomography computed tomography (PET-CT) before surgery. A total of 1409 three-dimensional radiomics features were extracted from the T2-weighted MR images (T2WI). The inactive group in the training cohort was balanced via the synthetic minority oversampling technique (SMOTE) method. The least absolute shrinkage and selection operator (LASSO) regression method was used for feature selection. The machine learning (ML) classifiers were logistic regression (LR), multilayer perceptron (MLP), and support vector machine (SVM). We used a fivefold cross-validation strategy in the training cohorts. The classification performance of the radiomics signature was evaluated using receiver operating characteristic curve (ROC) analysis in the training and test cohorts.

RESULTS

The radiomics features were significantly associated with the biological activity, and 10 features were selected to construct the radiomics model. The best performance of the radiomics model for the biological activity prediction was obtained by MLP (AUC = 0.830 ± 0.053; accuracy = 0.817; sensitivity = 0.822; specificity = 0.811).

CONCLUSIONS

We developed and validated a radiomics model as an adjunct tool to predict the HAE biological activity by combining T2WI images, which achieved results nearly equal to the PET-CT findings.

Prevalence of Hepatic Alveolar hydatid in a Nonendemic Region of North India in Hospital-based Population

Objective:

The objective of this study was to calculate the prevalence of hepatic alveolar hydatid disease in hospital-based population in North India, a nonendemic region for alveolar hydatid disease.

Materials and Methods:

This study was conducted at a tertiary care center in North India between April 2017 and March 2019. Patients with suspected hepatic alveolar hydatid on ultrasonography were evaluated with further imaging studies based on classical radiological findings and then confirmed by histopathology.

Results:

Twenty-five cases of hepatic alveolar hydatid were diagnosed primarily based on the classical imaging/radiological findings with histopathology confirmation, with a 2-year period prevalence of 0.207 cases/1000 population. Majority of the cases were in the age group of 41–60 years, with a mean age of 53.04 years. Fifty-two percent of the cases were female. Majority of them were from hilly areas and working with livestock animals. Abdominal pain was the most common presenting symptom.

Conclusion:

Hepatic alveolar hydatid is considered as a rare disease in India; however, the increased number of cases been diagnosed in our study could be either due to increased diagnostic modalities or due to actual increase in the number of cases. Therefore, hepatic alveolar hydatid should be considered in the differentials of suspicious liver mass in nonendemic regions.

Differential diagnosis between hepatic alveolar echinococcosis and intrahepatic cholangiocarcinoma with conventional ultrasound and contrast-enhanced ultrasound

BACKGROUND

Misclassifications of hepatic alveolar echinococcosis (HAE) as intrahepatic cholangiocarcinoma (ICC) may lead to inappropriate treatment strategies. The aim of this study was to explore the differential diagnosis with conventional ultrasound and contrast-enhanced ultrasound (CEUS).

METHODS

Sixty HAE lesions with 60 propensity score-matched ICC lesions were retrospectively collected. The 120 lesions were randomly divided into a training set (n = 80) and a testing set (n = 40). In the training set, the most useful independent conventional ultrasound and CEUS features was selected for differentiating between HAE and ICC. Then, a simplified US scoring system for diagnosing HAE was constructed based on selected features with weighted coefficients. The constructed US score for HAE was validated in both the training set and the testing set, and diagnostic performance was evaluated.

RESULTS

Compared with ICC lesions, HAE lesions were mostly located in the right lobe and had mixed echogenicity, a pseudocystic appearance and foci calcifications on conventional ultrasound. On CEUS, HAE lesions showed more regular rim-like enhancement than ICC lesions and had late washout with a long enhancement duration. The simplified US score consisted of echogenicity, pseudocystic/calcification, bile duct dilatation, enhancement pattern, enhancement duration, and marked washout. In the testing set, the sensitivity, specificity, LR+, LR- and the area under the ROC curve for the score to differentiate HAE from ICC were 80.0, 81.3%, 4.27, 0.25 and 0.905, respectively.

CONCLUSIONS

The US score based on typical features from both conventional ultrasound and CEUS could accurately differentiate HAE from ICC.

Alveolar Echinococcosis in Children

Alveolar echinococcosis (AE) is an infectious zoonotic disease that is caused by Echinococcus multilocularis. The disease is generally identified accidentally because of the long asymptomatic period, has a malignant behaviour, and mainly occurs in the liver. Usually it is diagnosed in adults and is very rare in pediatric patients. We report two cases of AE and 1 differential case between AE and cystic echinococcosis (CE) in children: two of them had lesions in the liver and one had rare extrahepatic presentation of a cyst in the spleen. All our patients received chemotherapy with albendazole because surgical treatment was not recommended. The children were followed-up from 10 to 30 months and no significant improvement was seen. In this report we discuss the difficulties we faced in the treatment and follow-up of these patients. We also review the main clinical manifestations, general diagnostic methods, and treatment options of AE according to the current literature.

Clinical aspects and treatment of alveolar echinococcosis: the current state of knowledge and difficulties in the diagnosis and management of cases in Poland

The aim of the study is to summarize the current state of knowlege in the diagnosis and monitoring of patients with alveolar echinococcosis (AE), using serological tests and imaging techniques, and to present the most recent therapeutic guidelines based on a literature review. The paper discusses the challenges in diagnosing and treating AE encountered in clinical practice in Poland, based on the analysis of medical records of 86 patients with AE, who were hospitalized in the University Centre for Maritime and Tropical Medicine (UCMTM) between 2000 and 2018. In Poland, AE is usually diagnosed at the advanced stage, when optimal, radical surgery is not an option. Diagnosis of AE is often preceded by invasive diagnostic methods, such as biopsy or exploratory laparotomy, which may result in the infection spreading. Pharmacological treatment is associated with potential adverse effects and is a significant financial burden for the patient due to the lack of reimbursement. There is a need to raise the awareness of AE among physicians performing imaging studies and to facilitate access to modern techniques enabling the assessment of the parasitic process.

Ultrasound images in hepatic alveolar echinococcosis and clinical stage of the disease

PURPOSE

Hepatic alveolar echinococcosis (AE) is a parasitic disease caused by the larval stage of the tapeworm Echinococcus multilocularis. Ultrasonography is the method of choice in the initial diagnosis of AE. The aim of the study is to present the most frequent sonomorphological patterns of lesions in hepatic AE based on the analysis of ultrasound findings in patients treated for AE at the University Centre of Maritime and Tropical Medicine (UCMMiT; Gdynia, Poland), and to establish whether there is a relationship between the clinical stage of AE and the occurrence of a specific sonomorphological pattern of hepatic lesions.

PATIENTS AND METHODS

We analysed the results of ultrasound examinations of 58 patients hospitalized in the UCMMiT with probable or certain diagnosis of AE. Liver lesions were assessed according to the classification developed by researchers from the University Hospital in Ulm (Germany). Statistical analysis was based on the relationship between the occurrence of a specific sonomorphological pattern of hepatic lesions and the clinical stage of AE.

RESULTS

The most frequently observed patterns of AE lesions in the liver were the hailstorm and the pseudocystic patterns. There was no correlation between the clinical stage of the disease and the ultrasonographic appearance of lesions. There was no statistically significant relationship between the more frequent occurrences of specific ultrasonographic patterns of lesions in the liver and radical or non-radical surgery.

CONCLUSIONS

The ultrasonographic appearance of the lesion in liver AE cannot determine the therapeutic management. Treatment plan should be established based on the PMN classification.

Deciphering the metabolic perturbation in hepatic alveolar echinococcosis: a 1H NMR-based metabolomics study

BACKGROUND

Hepatic alveolar echinococcosis (HAE) is caused by the growth of Echinococcus multilocularis larvae in the liver. It is a chronic and potentially lethal parasitic disease. Early stage diagnosis for this disease is currently not available due to its long asymptomatic incubation period. In this study, a proton nuclear magnetic resonance (1H NMR)-based metabolomics approach was applied in conjunction with multivariate statistical analysis to investigate the altered metabolic profiles in blood serum and urine samples obtained from HAE patients. The aim of the study was to identify the metabolic signatures associated with HAE.

RESULTS

A total of 21 distinct metabolic differences between HAE patients and healthy individuals were identified, and they are associated with perturbations in amino acid metabolism, energy metabolism, glyoxylate and dicarboxylate metabolism. Furthermore, the present results showed that the Fischer ratio, which is the molar ratio of branched-chain amino acids to aromatic amino acids, was significantly lower (P < 0.001) in the blood serum obtained from the HAE patients than it was in the healthy patient group.

CONCLUSIONS

The altered Fischer ratio, together with perturbations in metabolic pathways identified in the present study, may provide new insights into the mechanistic understanding of HAE pathogenesis and potential therapeutic interventions.

AE hepatic lesions: correlation between calcifications at CT and FDG-PET/CT metabolic activity

PURPOSE

To correlate the presence of calcifications in alveolar echinococcosis (AE) hepatic lesions to the metabolic activity in 18 fluorodeoxyglucose positron emission tomography combined with computed tomography (FDG-PET/CT).

METHODS

Our institutional review board approved this study. 61 patients (29 women, 32 men, aged from 15 to 86 years) were included in the study. Images of FDG-PET/CT were interpreted by two independent nuclear medicine physicians. AE hepatic lesions were classified as AE lesions with or without hypermetabolic activity. The presence of calcifications was assessed on unenhanced CT scans by two independent radiologists blinded with regard to the metabolic activity of the AE hepatic lesions. Every single calcification the size of which was < 3 mm and non-measurable calcifications which were forming areas with a powdery appearance were considered as microcalcifications. All other types of calcifications were reported as macrocalcifications. Statistical analysis was performed and p value < 0.05 was considered as statistically significant.

RESULTS

Microcalcifications and macrocalcifications were present at CT in 95% (58/61) AE hepatic lesions and 43% (26/61) AE hepatic lesions, respectively. Hypermetabolic activity was present at FDG-PET/CT in 93% (57/61) AE hepatic lesions. 98% (56/57) of the AE hepatic lesions presenting with hypermetabolic activity at FDG-PET/CT showed microcalcifications at CT (p = 0.01) when only 40% (23/57) showed macrocalcifications at CT (p = 0.3). 100% (23/23) of the AE hepatic lesions with hypermetabolic activity at FDG-PET/CT and macrocalcifications at CT showed also microcalcifications at CT.

CONCLUSIONS

Hypermetabolic activity of AE hepatic lesions at FDG-PET/CT is strongly correlated to the presence of microcalcifications at CT, independently of the presence of macrocalcifications.

Retrospective Study of Cystic Echinococcosis in a Recent Cohort of a Referral Center for Liver Surgery

BACKGROUND

Cystic echinococcosis (CE) is a zoonosis endemic in Spain caused by the larval stage of the cestode Echinococcus granulosus and is one of the 18 neglected tropical diseases recognized by the WHO. The aim of this study was to describe the epidemiological and clinical data of CE in a surgical referral hospital.

METHODS

A retrospective descriptive study of all adults' patients diagnosed with CE and followed at Vall d'Hebron University Hospital in Barcelona, Spain, between 2000 and 2015.

RESULTS

We found 151 cases, 78 (51.7%) women, and median age at diagnosis was 68 (range, 15-92) years. Diagnosis was a radiological finding in 97 (64.2%) and the most frequent location was the liver [135 (89.4%) patients]. Nearly 80% of the cysts were calcified and serology was positive in 48 (51.6%). The WHO-IWGE classification was only available in 70 of the 104 (67.3%) cases of liver cysts that had an ultrasound. First therapeutic plan was "watch and wait" followed by surgery. International recommendations were not always followed, particularly in CE4 and CE5 stages, and 20% needed a change of treatment because of progression or recurrence. Patients treated surgically were younger, more symptomatic, and had larger and less calcified cysts in multiple sites. Serology was not useful for CE diagnosis and neither serology nor calcification of the cyst helped to predict viability.

CONCLUSIONS

The formation of multidisciplinary teams in reference hospitals could help to improve CE diagnosis, its management, and follow-up, since international recommendations are not usually followed.

Echinococcosis: Advances in the 21st Century

Echinococcosis is a zoonosis caused by cestodes of the genus Echinococcus (family Taeniidae). This serious and near-cosmopolitan disease continues to be a significant public health issue, with western China being the area of highest endemicity for both the cystic (CE) and alveolar (AE) forms of echinococcosis. Considerable advances have been made in the 21st century on the genetics, genomics, and molecular epidemiology of the causative parasites, on diagnostic tools, and on treatment techniques and control strategies, including the development and deployment of vaccines. In terms of surgery, new procedures have superseded traditional techniques, and total cystectomy in CE, ex vivo resection with autotransplantation in AE, and percutaneous and perendoscopic procedures in both diseases have improved treatment efficacy and the quality of life of patients. In this review, we summarize recent progress on the biology, epidemiology, diagnosis, management, control, and prevention of CE and AE. Currently there is no alternative drug to albendazole to treat echinococcosis, and new compounds are required urgently. Recently acquired genomic and proteomic information can provide a platform for improving diagnosis and for finding new drug and vaccine targets, with direct impact in the future on the control of echinococcosis, which continues to be a global challenge.