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Échinococcose alvéolaire. Presse Med 2009; 38:852-5. [DOI: 10.1016/j.lpm.2008.05.023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/02/2008] [Revised: 04/17/2008] [Accepted: 05/05/2008] [Indexed: 11/20/2022] Open
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Long-term experience on surgical treatment of alveolar echinococcosis. Langenbecks Arch Surg 2008; 394:689-98. [PMID: 18651165 DOI: 10.1007/s00423-008-0392-5] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2008] [Accepted: 07/03/2008] [Indexed: 12/13/2022]
Abstract
INTRODUCTION Alveolar echinococcosis (AE) is life-threatening and reports on surgical procedures and results are rare, but essential. MATERIALS AND METHODS Longitudinal surveillance and long-term follow-up of patients surgically treated for AE during the periods 1982-1999 (group A) and 2000-2006 (group B). SETTING University hospital within an endemic area. RESULTS The median (min-max) follow-up period was 141 (5-417) months. Forty-eight surgical procedures were performed in 36 patients with AE: 63% were partial resections of the liver (additional extrahepatic resection in ten of them), 17% just extrahepatic resections, 10% biliodigestive anastomosis, and 10% exploratory laparotomies. Seventy-five percent of the operations were first-time procedures, 25% done due to a relapse. Forty-two percent of the operations were estimated to be curative (R0), whereas 58% were palliative (R1, R2). All patients had additional medical treatment and periodical follow-up. Two out of 18 (11%) patients, estimated to have had curative surgery, developed a relapse 42 and 54 months later. R0-resection rates depended on the primary, neighboring, metastasis stage of AE (S1, 100%; S2, 100%; S3a, 33%; S3b, 27%; S4, 11%). During the period 2000-2006 elective radical surgery for AE was done only if a safe distance of at least 2 cm was attainable. This concept was associated with an increased R0-resection rate of 87% for group B compared to 24% for group A. Operative procedures done to control complicated courses of AE (jaundice, cholangitis, vascular compression, bacterial superinfection) have not been curative (R2) in 82% because the disease had spread into irresectable structures. Morbidity was 19%. All patients with curative resections are alive. Fifty-six percent of the patients with palliative treatment are alive as long as 14-237 months, 28% died from AE 164-338 months after diagnosis (late lethality), and 17% died due to others diseases 96-417 months after diagnosis of AE. One out of seven (14%) patients suffering from suppurative parasitic necrosis died because it was impossible to control systemic sepsis (3% hospital lethality). CONCLUSION Curative surgery for AE is feasible if the parasitic mass is removable entirely. The earlier the stage, the more frequent is R0 resectability. The observance of a minimal safe distance increases the rate of R0 resections. The benefit of palliative surgery is uncertain due to favorable long-term results of medical treatment alone. However, necrotic tissue is at risk of bacterial superinfection, which can cause life-threatening sepsis. Palliative surgery is an option to treat complications, which could not be managed otherwise.
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Torgerson PR, Schweiger A, Deplazes P, Pohar M, Reichen J, Ammann RW, Tarr PE, Halkic N, Müllhaupt B. Alveolar echinococcosis: from a deadly disease to a well-controlled infection. Relative survival and economic analysis in Switzerland over the last 35 years. J Hepatol 2008; 49:72-7. [PMID: 18485517 DOI: 10.1016/j.jhep.2008.03.023] [Citation(s) in RCA: 167] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/04/2008] [Accepted: 03/03/2008] [Indexed: 02/07/2023]
Abstract
BACKGROUND/AIMS Alveolar echinococcosis (AE) is a serious liver disease. The aim of this study was to explore the long-term prognosis of AE patients, the burden of this disease in Switzerland and the cost-effectiveness of treatment. METHODS Relative survival analysis was undertaken using a national database with 329 patient records. 155 representative cases had sufficient details regarding treatment costs and patient outcome to estimate the financial implications and treatment costs of AE. RESULTS For an average 54-year-old patient diagnosed with AE in 1970 the life expectancy was estimated to be reduced by 18.2 and 21.3 years for men and women, respectively. By 2005 this was reduced to approximately 3.5 and 2.6 years, respectively. Patients undergoing radical surgery had a better outcome, whereas the older patients had a poorer prognosis than the younger patients. Costs amount to approximately Euro108,762 per patient. Assuming the improved life expectancy of AE patients is due to modern treatment the cost per disability-adjusted life years (DALY) saved is approximately Euro6,032. CONCLUSIONS Current treatments have substantially improved the prognosis of AE patients compared to the 1970s. The cost per DALY saved is low compared to the average national annual income. Hence, AE treatment is highly cost-effective in Switzerland.
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Affiliation(s)
- Paul R Torgerson
- Institute of Parasitology, University of Zürich, CH-8057 Zürich, Switzerland
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Ozkok A, Gul E, Okumus G, Yekeler E, Gulluoglu MG, Kiyan E, Arseven O. Disseminated alveolar echinococcosis mimicking a metastatic malignancy. Intern Med 2008; 47:1495-7. [PMID: 18703862 DOI: 10.2169/internalmedicine.47.1228] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Alveolar echinococcosis, which is caused by Echinococcus multilocularis, is a very aggressive and potentially fatal infestation which always affects the liver primarily and metastasizes to any part of the body. Imaging studies are usually highly suspicious of carcinoma or sarcoma, and biopsy may provide the first indication of infection. We report a case of disseminated alveolar echinococcosis with liver, lung, and bone involvement mimicking a metastatic malignancy.
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Affiliation(s)
- Abdullah Ozkok
- Istanbul Faculty of Medicine, Department of Internal Medicine, Istanbul University, Istanbul, Turkey.
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Schweiger A, Ammann RW, Candinas D, Clavien PA, Eckert J, Gottstein B, Halkic N, Muellhaupt B, Prinz BM, Reichen J, Tarr PE, Torgerson PR, Deplazes P. Human alveolar echinococcosis after fox population increase, Switzerland. Emerg Infect Dis 2007; 13:878-82. [PMID: 17553227 PMCID: PMC2792858 DOI: 10.3201/eid1306.061074] [Citation(s) in RCA: 207] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
An increase in fox population has led to an increase in incidence of human alveolar echinococcosis. We analyzed databases spanning 50 years, which included retrospective alveolar echinococcosis (AE) case-finding studies and databases of the 3 major centers for treatment of AE in Switzerland. A total of 494 cases were recorded. Annual incidence of AE per 100,000 population increased from 0.12– 0.15 during 1956–1992 and a mean of 0.10 during 1993–2000 to a mean of 0.26 during 2001–2005. Because the clinical stage of the disease did not change between observation periods, this increase cannot be explained by improved diagnosis. Swiss hunting statistics suggested that the fox population increased 4-fold from 1980 through 1995 and has persisted at these higher levels. Because the period between infection and development of clinical disease is long, the increase in the fox population and high Echinococcus multilocularis prevalence rates in foxes in rural and urban areas may have resulted in an emerging epidemic of AE 10–15 years later.
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Affiliation(s)
- Alexander Schweiger
- University of Zurich, Zurich, Switzerland
- This author submitted this article to the University of Zurich as part of his Doctor of Medicine postgraduate degree requirement
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Ehrhardt AR, Reuter S, Buck AK, Haenle MM, Mason RA, Gabelmann A, Kern P, Kratzer W. Assessment of disease activity in alveolar echinococcosis: a comparison of contrast enhanced ultrasound, three-phase helical CT and [(18)F] fluorodeoxyglucose positron emission tomography. ACTA ACUST UNITED AC 2007; 32:730-6. [PMID: 17285403 DOI: 10.1007/s00261-006-9173-1] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
BACKGROUND Objective of the present study was to assess activity or vascularization of focal liver lesions in alveolar echinococcosis (AE) using [18F]fluorodeoxyglucose positron emission tomography (FDG-PET) in comparison with contrast enhanced ultrasound (CEUS) and three-phase helical computed tomography (CT). METHODS In this prospective study, 17 patients with confirmed AE of the liver were included (6 males, 11 females; average age: 59 +/- 16 years; average duration of disease: 10.5 years) and were then examined using FDG-PET, precontrast ultrasound (US), CEUS, and three-phase helical CT. We assessed metabolic activity (FDG-PET) and vascularization (CEUS and CT) of Echinococcus multilocularis specific hepatic lesions. RESULTS FDG-PET identified increased metabolic activity in the corresponding lesions in seven patients (41.2%). A vascularization pattern of echinococcal lesions was visualized in 9 patients (52.9%) by CEUS and in 4 patients (23.5%) by CT. All positive FDG-PET findings were also positive at CEUS. CONCLUSIONS There was association between findings of metabolic activity in AE at FDG-PET and vascularized lesions of the liver returned by CEUS. This suggests that CEUS may represent a cost-effective tool in the decision making to perform FDG-PET examination.
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Affiliation(s)
- Alexander R Ehrhardt
- Department of Internal Medicine I, University Hospital Ulm, Robert-Koch-Str. 8, 89081, Ulm, Germany.
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Koroglu M, Akhan O, Gelen MT, Koroglu BK, Yildiz H, Kerman G, Oyar O. Complete resolution of an alveolar echinococcosis liver lesion following percutaneous treatment. Cardiovasc Intervent Radiol 2006; 29:473-8. [PMID: 16228851 DOI: 10.1007/s00270-005-0017-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Herein we present a 63-year-old male patient with a solid hepatic alveolar echinococcosis diagnosed by surgical biopsy. His liver lesion, which was infected, was drained by percutaneous catheterization. The lesion surprisingly disappeared completely after the treatment. The patient was followed-up without any symptoms for 20 months after the drainage. As alveolar echinococcosis of the liver behaves like a slow-growing liver cancer, the disappearance of our patient's lesion was a very unusual and rare outcome, which, to the best of our knowledge, has never been published in the literature.
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Affiliation(s)
- Mert Koroglu
- Department of Radiology, Faculty of Medicine, Suleyman Demirel University, Isparta, Turkey.
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Bresson-Hadni S, Delabrousse E, Blagosklonov O, Bartholomot B, Koch S, Miguet JP, Mantion GA, Vuitton DA. Imaging aspects and non-surgical interventional treatment in human alveolar echinococcosis. Parasitol Int 2006; 55 Suppl:S267-72. [PMID: 16403670 DOI: 10.1016/j.parint.2005.11.053] [Citation(s) in RCA: 121] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Alveolar echinococcosis (AE) of the liver caused by the metacestode of the fox tapeworm Echinococcus multilocularis is characterized by a multivesicular structure surrounded by an extensive fibro-inflammatory host reaction. The lesions behave like a slow-growing liver cancer, without sharp limits between the parasitic tissue and the liver parenchyma. Invasion of biliary and vascular walls is another hallmark of this severe disease. Moreover, the poor vascularization of the parasitic mass often leads to necrosis in the central part of the lesion. This explains why liver abscess due to superimposed bacterial infection of the necrotic area may occur in this disease. Currently, a range of imaging techniques can be used at the different stages of management of AE. For diagnosis, ultrasonography remains the first line examination. For a more accurate disease evaluation, aiming to guide the surgical strategy, computerized tomography, Magnetic Resonance (MR) imaging, including cholangio-MR imaging are of importance, providing useful complementary information. More recently, Positive-Emission Tomography using [18F] fluoro-deoxyglucose has been developed for the follow-up of inoperable AE patients under long-term benzimidazoles therapy. This approach seems very promising to assess inflammatory activity and thereby to indirectly depict parasitic activity. Non-surgical interventional procedures, mainly percutaneous biliary and/or centro-parasitic abscesses drainages, are currently a major aspect in the care of incurable AE patients and have largely contributed to the improvement of survival in this situation during the past 20 years. They may also be used as a bridge before a curative surgical procedure in symptomatic patients presenting a life-threatening bacterial and/or fungal infection. It is also very useful in inoperable patients to overcome similar infectious episodes.
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Kern P, Wen H, Sato N, Vuitton DA, Gruener B, Shao Y, Delabrousse E, Kratzer W, Bresson-Hadni S. WHO classification of alveolar echinococcosis: principles and application. Parasitol Int 2005; 55 Suppl:S283-7. [PMID: 16343985 DOI: 10.1016/j.parint.2005.11.041] [Citation(s) in RCA: 205] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Alveolar echinococcosis is caused by the larval stage of the fox tapeworm (Echinococcus multilocularis) and is frequently diagnosed as a space occupying lesion in the liver. The growth pattern resembles that of a malignant tumor with infiltration throughout the liver, spreading into neighbouring organs and metastases formation in distant organs. Thus, one of the prevailing differential diagnoses is liver cancer. Guided by the Tumor-Node-Metastasis (TNM) system of liver cancer, the European Network for Concerted Surveillance of Alveolar Echinococcosis and the WHO Informal Working Group on Echinococcosis proposed a clinical classification for alveolar echinococcosis. It was designated as PNM system (P = parasitic mass in the liver, N = involvement of neighbouring organs, and M = metastasis). As for TNM in oncology, single PNM categories were combined into four stages, I to IV. The system was developed by a retrospective analysis of 97 patients' records from two treatment centers (Besançon/France and Ulm/Germany). Recently, this WHO classification was applied to 222 patients in 4 clinical centers around the world (Besançon/France, n = 26; Urumqi/China, n = 46; Sapporo/Japan, n = 58; and Ulm/Germany, n = 92). All patients could be classified who had been diagnosed in the period from January 1998 to June 2005. The stage grouping indicated center differences, but appeared to segregate patients according to various treatment regimens. The WHO classification not only serves as a tool for the international standardization of disease manifestation but also aids to evaluate the outcome of a chosen diagnostic and treatment procedure in different treatment centers in Europe and Asia.
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Affiliation(s)
- Peter Kern
- Division of Infectious Diseases, University Hospital and Medical Center, Robert-Koch-Str. 8, D-89081 Ulm, Germany.
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Kratzer W, Reuter S, Hirschbuehl K, Ehrhardt AR, Mason RA, Haenle MM, Kern P, Gabelmann A. Comparison of contrast-enhanced power Doppler ultrasound (Levovist) and computed tomography in alveolar echinococcosis. ACTA ACUST UNITED AC 2005; 30:286-90. [PMID: 15965776 DOI: 10.1007/s00261-004-0263-7] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
BACKGROUND To date, no study has compared unenhanced and contrast-enhanced (Levovist) power Doppler ultrasound with three-phase helical computed tomography (CT) for the analysis of the vascularization of hepatic lesions in patients who have alveolar echinococcosis. METHODS Fifteen patients (11 female and four male; average age, 45.8 years) with confirmed Echinococcus multilocularis infection underwent unenhanced and contrast-enhanced (Levovist) power Doppler ultrasound (2- to 5-MHz transducer head) and three-phase helical CT. The largest identified lesion in each patient was studied. RESULTS CT visualized vascularization peripheral or central to the largest echinococcal lesions in 11 of 15 patients. Vascularization in the area of the echinococcal lesions was not visualized by unenhanced or contrast-enhanced power Doppler ultrasound in any of the 15 patients studied. CONCLUSION Three-phase helical CT visualizes the vascularization associated with Echinococcus multilocularis lesions in the liver. Neither unenhanced nor contrast-enhanced ultrasound in power mode is suitable for this application.
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Affiliation(s)
- W Kratzer
- Abteilung Innere Medizin I, Universität Ulm, Robert-Koch-Strasse 8, D-89081 Ulm, Germany.
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Scharf G, Deplazes P, Kaser-Hotz B, Borer L, Hasler A, Haller M, Flückiger M. Radiographic, ultrasonographic, and computed tomographic appearance of alveolar echinococcosis in dogs. Vet Radiol Ultrasound 2004; 45:411-8. [PMID: 15487566 DOI: 10.1111/j.1740-8261.2004.04074.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Alveolar echinococcosis is a rare metacestodal infection of humans and domestic animals with Echinococcus multilocularis and predominantly affects the liver. In humans, diagnosis is based on serology, ultrasonography, computed tomography (CT), and magnetic resonance imaging (MRI), techniques that have not yet been validated for the diagnosis of alveolar echinococcosis in dogs. Therefore, the purpose of this retrospective study was to describe the radiographic, ultrasonographic, and CT appearance of canine alveolar echinococcosis. Eleven dogs with confirmed alveolar echinococcosis (PCR or histology from biopsy material of metacestode tissue) diagnosed between 1995 and 2003 were included in the study. The age of the dogs at initial presentation ranged from 7 months to 10.5 years. Abdominal radiographs were made in nine animals, abdominal ultrasonography was performed in 10 dogs, and two CT studies in one dog, respectively. The history, clinical presentation, and laboratory findings for the 11 dogs were unspecific, the most frequent clinical finding being nonpainful progressive abdominal distention. All radiographed dogs had large liver masses; they contained small mineralizations in five. The most frequent ultrasonographic finding was multiple large cavitary masses with or without wall mineralizations. Seven animals received surgical and subsequent medical therapy with albendazole (10mg/kg) and all went into clinical remission. This study reviewed for the first time imaging findings associated with alveolar echinococcosis. The disease has to be included in the list of differential diagnoses in dogs with large, cavitary liver masses, particularly when mineralization is noted.
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Affiliation(s)
- Gernot Scharf
- Diagnostic Imaging and Radio-Oncology, University of Zurich, Winterthurerstrasse 260, 8057 Zu- rich, Switzerland.
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Reuter S, Buck A, Grebe O, Nüssle-Kügele K, Kern P, Manfras BJ. Salvage treatment with amphotericin B in progressive human alveolar echinococcosis. Antimicrob Agents Chemother 2004; 47:3586-91. [PMID: 14576122 PMCID: PMC253803 DOI: 10.1128/aac.47.11.3586-3591.2003] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Most patients with alveolar echinococcosis are diagnosed at a late stage when the disease has advanced to unresectable hepatic lesions. These patients require lifelong therapy with benzimidazoles, the only medical treatment currently available. To date, no treatment option remains for patients with benzimidazole intolerance or treatment failure. Amphotericin B was recently shown to exert antiparasitic activity in vitro. Here, we report the efficacy of amphotericin B in human alveolar echinococcosis. In three patients with extensive disease and without further treatment options, disease progression had been documented over several months. They were treated with amphotericin B intravenously at a dose of 0.5 mg/kg of body weight three times per week. Follow-up parameters were physical examination, laboratory parameters, and imaging techniques. Amphotericin B treatment effectively halted parasite growth in all three patients. The antiparasitic effect was most evident by spontaneous closure of cutaneous fistulae in two patients and by constant size of parasitic lesions during treatment, as assessed radiologically. Metabolic activity in parasitic areas was visualized by positron emission tomography and significantly decreased during treatment. However, progressive affection of the heart in one patient could not be stopped. All patients currently continue on amphotericin B and have been treated for 25, 17, and 14 months, respectively. We introduce amphotericin B as salvage treatment for alveolar echinococcosis patients with intolerance or resistance to benzimidazoles, as it effectively suppresses parasite growth. Amphotericin B is not parasitocidal; therefore long-term treatment has to be anticipated.
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Affiliation(s)
- Stefan Reuter
- Section of Infectious Diseases and Clinical Immunology, Department of Medicine III, University Hospital of Ulm, Ulm, Germany
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Suzuki Y, Fujimoto Y, Hosoki Y, Suzuki M, Inoue M, Sakurai S, Ohtake T, Ohhira M, Saito H, Kohgo Y. Usefulness of contrast-enhanced wide-band Doppler ultrasonograpy to diagnose alveolar echinococcosis of the liver and evaluate the effect of the treatment. Eur J Radiol 2004; 48:305-11. [PMID: 14652151 DOI: 10.1016/s0720-048x(03)00005-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Alveolar echinococcosis is a rare parasitic disease caused by Echinococcus multicularis and most commonly involves the liver. Early diagnosis and accurate evaluation of the effect of the treatment are essential to improve the prognosis of patients with alveolar echinococcosis of the liver (AEL). The aim of this study was to demonstrate the characteristic imaging of AEL by contrast-enhanced Dynamic Flow (CE-DF) employing a wide-band Doppler technique for the diagnosis and the accurate evaluation of the effect of the treatment. Four patients with five AEL lesions before treatment or during medication were examined by CE-DF. All of the five AEL lesions examined by CE-DF revealed a defect with an irregular and distinct margin like a worm-eaten defect appearance, which was never observed on other hepatic lesions, in liver perfusion image during post-vascular phase. In addition, CE-DF made it possible to measure the size of AEL lesions accurately because the margin was detected distinctly. These data suggest that CE-DF is clinically useful for the diagnosis of AEL and the evaluation of the effect of the treatment.
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Affiliation(s)
- Yasuaki Suzuki
- Third Department of Internal Medicine, Asahikawa Medical College, 2-1, Midorigaoka-Higashi, Asahikawa 078-8510, Japan
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Abstract
Echinococcosis is one of the world's most geographically widespread parasitic zoonoses, with transmission occurring in tropical, temperate and arctic biomes. Most human infections are due to Echinococcus granulosus transmitted between domestic dogs and livestock, but this cosmopolitan species also cycles between wild carnivores (principally canids) and wild ungulates. The other species with significant zoonotic potential is E. multilocularis that occurs naturally in fox definitive hosts and small mammal intermediate hosts. These two species cause human cystic or alveolar echinococcosis respectively, which may be considered serious public health problems in several regions including developed countries. This review provides an introductory overview to the Supplement and summarises the biology and epidemiology of these two related cestodes with an emphasis on applied aspects relating to detection, diagnosis and surveillance in animal and human populations, and includes aspects of transmission ecology, and also considers aspects of community epidemiology and potential for control.
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Affiliation(s)
- Stefania Proietti
- Department of Radiology, Centre Hospitalier Universitaire Vaudois, Lausanne, Switzerland.
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Harman M, Arslan H, Kotan C, Etlik O, Kayan M, Deveci A. MRI findings of hepatic alveolar echinococcosis. Clin Imaging 2004; 27:411-6. [PMID: 14585571 DOI: 10.1016/s0899-7071(03)00006-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Diagnosis of liver infestation by alveolar echinococcosis (AE) is based on serologic, sonographic and computed tomography (CT) findings. Experience with magnetic resonance imaging (MRI) demonstrates that features of this disease are limited. CT and MRI findings of 14 cases with hepatic AE were compared in this report. We have described the MRI appearance of hepatic AE, which exhibits variable signal intensities on T1- and T2-weighted images. Fibrous and parasitic tissue showed low signal both on T1- and, generally, on T2-weighted images. In a few cases, a high signal on T2-weighted images may be observed, due either to central necrotic zones or to small peripheral cyst. MRI than by CT was more easily identified central necrosis. However, MRI seemed to be less effective than CT in allowing us to reach a positive diagnosis, due to its inability to show microcalcifications. In addition, MRI may not reveal small lesions. In most cases, T1-weighted images revealed more clearly than CT did the margins of the lesions and the hepatic extension, especially to hepatic veins, vena cava and perihepatic spaces.
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Affiliation(s)
- M Harman
- Department of Radiology, University of Yuzuncu Yil Faculty of Medicine, Van, Turkey.
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Reuter S, Buck A, Manfras B, Kratzer W, Seitz HM, Darge K, Reske SN, Kern P. Structured treatment interruption in patients with alveolar echinococcosis. Hepatology 2004; 39:509-17. [PMID: 14768005 DOI: 10.1002/hep.20078] [Citation(s) in RCA: 115] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
In human alveolar echinococcosis (AE), benzimidazoles are given throughout life because they are only parasitostatic. It has been a longstanding goal to limit treatment, and recent reports suggest that, in selected cases, benzimidazoles may be parasitocidal. Previously, we showed that positron -emission tomography (PET) using [(18)F]fluoro-deoxyglucose discriminates active from inactive lesions in AE. We have now performed a 3-year prospective study in 23 patients and conducted a structured treatment interruption in those without signs of PET activity. Disease progression was further assessed by ultrasound, computerized tomography, laboratory parameters, and clinical examination. We found PET-negative lesions in 15 of 23 patients and benzimidazoles were discontinued in these patients. After 18 months, patients were reevaluated, and, of the 15 initially PET-negative patients, 8 showed either new activity on PET (n = 6) or signs of clinical progression (n = 2). Reinitiation of benzimidazoles halted parasite growth again. No further progression was detected after 36 months. PET had a sensitivity of 91% for the detection of active lesions. In conclusion, despite successful suppression of metabolic activity, in most cases benzimidazoles do not kill the parasite. PET is a reliable tool for assessing metabolic activity and for timely detection of relapses. Neither duration of treatment, kind of treatment, lesion size, calcifications, or regressive changes reliably indicate parasite death. We discourage the discontinuation of benzimidazoles in inoperable AE even after many years of treatment. However, patients with a poor compliance of benzimidazole intake or patients suffering from side effects to benzimidazoles might be assessed for PET negativity. If permanent discontinuation of benzimidazoles is attempted, the course of disease should be followed by PET.
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Affiliation(s)
- Stefan Reuter
- Section of Infectious Diseases and Clinical Immunology, Department of Medicine III, University Hospital of Ulm, Germany
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Eckert J, Deplazes P. Biological, epidemiological, and clinical aspects of echinococcosis, a zoonosis of increasing concern. Clin Microbiol Rev 2004; 17:107-35. [PMID: 14726458 PMCID: PMC321468 DOI: 10.1128/cmr.17.1.107-135.2004] [Citation(s) in RCA: 1089] [Impact Index Per Article: 54.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Echinococcosis in humans is a zoonotic infection caused by larval stages (metacestodes) of cestode species of the genus Echinococcus. Cystic echinococcosis (CE) is caused by Echinococcus granulosus, alveolar echinococcosis (AE) is caused by E. multilocularis, and polycystic forms are caused by either E. vogeli or E. oligarthrus. In untreated cases, AE has a high mortality rate. Although control is essentially feasible, CE remains a considerable health problem in many regions of the northern and southern hemispheres. AE is restricted to the northern hemisphere regions of North America and Eurasia. Recent studies have shown that E. multilocularis, the causative agent of AE, is more widely distributed than previously thought. There are also some hints of an increasing significance of polycystic forms of the disease, which are restricted to Central and South America. Various aspects of human echinococcosis are discussed in this review, including data on the infectivity of genetic variants of E. granulosus to humans, the increasing invasion of cities in Europe and Japan by red foxes, the main definitive hosts of E. multilocularis, and the first demonstration of urban cycles of the parasite. Examples of emergence or reemergence of CE are presented, and the question of potential spreading of E. multilocularis is critically assessed. Furthermore, information is presented on new and improved tools for diagnosing the infection in final hosts (dogs, foxes, and cats) by coproantigen or DNA detection and the application of molecular techniques to epidemiological studies. In the clinical field, the available methods for diagnosing human CE and AE are described and the treatment options are summarized. The development of new chemotherapeutic options for all forms of human echinococcosis remains an urgent requirement. A new option for the control of E. granulosus in the intermediate host population (mainly sheep and cattle) is vaccination. Attempts are made to reduce the prevalence of E. multilocualaris in fox populations by regular baiting with an anthelmintic (praziquantel). Recent data have shown that this control option may be used in restricted areas, for example in cities, with the aim of reducing the infection risk for humans.
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Affiliation(s)
- Johannes Eckert
- Institute of Parasitology, University of Zurich, CH-8057 Zurich, Switzerland.
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Abstract
PURPOSE OF REVIEW Echinococcus multilocularis is a tapeworm of foxes that may cause a zoonotic infection resulting in a highly pathogenic and potentially fatal chronic liver infestation called human alveolar echinococcosis. Radical liver resection currently offers the only potential cure. Although alveolar echinococcosis is a rare parasitic disease that is restricted to transmission in the northern hemisphere, the parasite is geographically widespread being distributed from Alaska, across Canada and north central USA, through northern Europe and Eurasia to Japan. The present review summarizes the background to this helminthic infection and recent contributions in areas of pathology, diagnosis, treatment and transmission. RECENT FINDINGS Concern is growing in Europe that the prevalence and distribution of E. multilocularis in red foxes has increased significantly in the last 10-15 years. A retrospective analysis revealed >550 cases of human alveolar echinococcosis diagnosed between 1982-2000, with the majority in France, Germany and Switzerland. Human prevalence rates >3% occur in central northwest China and the disease is of public health concern in northern Japan. Improvements in immunodiagnosis with native and recombinant antigens have enabled more accurate confirmation of hepatic image findings, while development of in-vitro culture of metacestode tissues provides a useful model for screening new anti-alveolar echinococcosis drugs as alternatives to albendazole and surgery. Recombinant molecules from the oncosphere and metacestode stages have shown potential as vaccine candidates. New tools of coproantigen and copro-DNA detection for vulpine infections have proved highly beneficial in epidemiological and transmission ecology studies, as has a landscape ecology approach to develop risk models for communities in endemic areas. SUMMARY It is possible that human AE will become an emergent zoonosis in some regions of Europe and Eurasia. Improvements in diagnostic and treatment approaches are being investigated. Further understanding of host immune responses will aid in characterization of disease pathology. Control of E. multilocularis in its natural cycles will be difficult due to the involvement of wild animal hosts, however use of anthelminthic baits and dosing of domestic dogs may reduce transmission at local scales.
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Affiliation(s)
- Philip Craig
- Bioscience Research Institute and School of Environment and Life Sciences, University of Salford, Salford, Greater Manchester, M5 4WT, UK.
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Buttenschoen K, Carli Buttenschoen D. Echinococcus granulosus infection: the challenge of surgical treatment. Langenbecks Arch Surg 2003; 388:218-30. [PMID: 12845535 DOI: 10.1007/s00423-003-0397-z] [Citation(s) in RCA: 85] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2002] [Accepted: 05/21/2003] [Indexed: 12/13/2022]
Abstract
BACKGROUND Cystic echinococcosis (CE) is a worldwide zoonosis caused by larval stages of the cestode Echinococcus granulosus. Surgery, chemotherapy, and interventional procedures are the therapeutic options. Surgery can cure the patient if the parasite is removed entirely. However, the technical procedures are inconsistent and comprise partial liver resection or opening of the parasitic cyst and removal of the parasite. Laparotomy is the most common approach. In selected cases laparoscopic methods are successful. Retrospective studies outweigh prospective ones by far. However, proper management gives favorable results. METHODS We critically review the literature and present a brief summary of current surgical strategy and focus on issues relevant for surgeons: diagnosis, indication for medical treatment, indication for surgical treatment, surgical procedures, scolicidal agents, morbidity, mortality, recurrence, perioperative medication, standards. RESULTS All surgical procedures aim at the complete removal of the parasite. Liver resection and pericystectomy are procedures that resect the closed cysts with a fairly wide safety margin. A meta-analysis shows the best results regarding lethality (1.2%), morbidity (11.7%), and recurrence rates (2%) for resective operations. However, most surgeons consider these methods as too radical for a benign disease. Procedures that remove the parasite and keep the pericyst (=cystectomy) are easier to carry out than resective ones. The meta-analysis presented revealed a lethality of 2%, morbidity of 23%, and recurrence rate of 10.4% for these operations. Omentoplasty is the option of choice for the management of the remaining cyst cavity. Despite alternative procedures surgery is the treatment of choice. Supportive measures comprise the use of scolicidal agents and postoperative benzimidazole administration. However, a critical review of the literature disclosed a lack of scientific confirmation of established treatment modalities and procedures. The results of ultrasound imaging were classified and correlated to the developmental phases of CE. CONCLUSIONS Cystectomy and omentoplasty for CE should be the standard surgical procedure because it is safe, simple, and effective and meets all criteria of surgical treatment for hydatid disease: entire elimination of the parasite, no intraoperative spillage especially by using a cone, and saving healthy tissue. Pericystectomy should be used for peripherally located liver cysts that are surrounded by parenchyma only partially. Ultrasonic classification of the parasitic lesion should be used as a guideline for therapeutic measures.
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Affiliation(s)
- K Buttenschoen
- Department of Surgery, University of Ulm, Steinhoevelstrasse 9, 89075 Ulm, Germany.
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Abstract
Two Echinococcus species may exhibit medical relevance as causative agents of pulmonary forms of echinococcosis. Most importantly, infections with Echinococcus granulosus result in "cystic hydatid disease" or "cystic echinococcosis," which affects the lungs in a considerable ratio of cases. Echinococcus multilocularis, which causes "alveolar echinococcosis," affects the lungs relatively rarely and then usually upon metastasizing from primary hepatic lesions. Cystic echinococcus and alveolar echinococcus differ pathologically and clinically so greatly that they are considered separately in this article, although alveolar echinococcus is covered minimally because of its minor importance regarding lung infections.
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Affiliation(s)
- Bruno Gottstein
- Institute of Parasitology, University of Berne, Länggass-Strasse 122, CH-3012 Berne, Switzerland.
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