Relevance of Pulmonary Alveolar Echinococcosis

Echinococcoses - A Primer for Radiologists

BACKGROUND

Cystic (CE) and alveolar (AE) echinococcoses are zoonotic parasitoses that may pose diagnostic problems due to their relative rarity in Middle Europe.

METHODS

Based on a recent literature search and the observation of casuistics from a national echinococcosis treatment center, epidemiological, radiological, and therapeutic fundamentals are presented and important differences between AE and CE are discussed.

RESULTS AND CONCLUSION

AE and CE must be regarded as completely different diseases, which differ from each other in every significant aspect. This applies not only to the epidemiological background of the patients but also to the biology of the diseases and their respective imaging features.

KEY POINTS

· AE and CE are very distinct from one another and must be considered separately.. · AE is endemic in Middle Europe and is known as malignant parasitosis due to its destructive growth form.. · CE is primarily seen in Middle Europe in individuals with migration background and has a rather benign character..

CITATION FORMAT

· Weber TF, Mokry T, Stojkovic M. Die Echinokokkosen - Einblicke aus Sicht der Radiologie. Fortschr Röntgenstr 2023; 195: 1106 - 1121.

Chylothorax due to hepatic alveolar echinococcosis with infiltration of diaphragm and left pleura: a case report

BACKGROUND

Alveolar echinococcosis (AE) is an endemic parasitic zoonosis in Germany. In most cases, the liver is the primary organ affected.

CASE PRESENTATION

A 59-year old female patient presented with increasing exertional dyspnea and unintentional weight loss. A computed tomography (CT) scan showed a left-sided chylous pleural effusion and multiple intrahepatic masses with infiltration of the diaphragm and the pleura. The findings were initially misinterpreted as hepatocellular carcinoma (HCC) with infiltrating growth. Liver biopsy of one of the masses showed no evidence of malignancy, but an amorphous necrosis of unclear origin. HCC was further ruled out by magnetic resonance imaging (MRI). However, MRI findings were highly suspicious for hepatothoracic dissemination and complications due to AE. Typical histologic findings in a repeated and more specific examination of the liver tissue and a positive serology for echinococcosis confirmed the diagnosis of AE. As the hepatic and pulmonary manifestations were considered inoperable in a curative matter, an anti-parasitic treatment with albendazole was initiated. A video-assisted thoracoscopic surgery (VATS) with removal of the chylous effusion as well as a talc pleurodesis was performed to relieve the patient from dyspnea. Two months later, the patient was asymptomatic and a positron emission tomography (PET)-CT-scan with [18 F] fluoro-2-deoxy-d-glucose (FDG) showed a remarkable diminution of the hepatic manifestation.

CONCLUSIONS

This case demonstrates a rare presentation of alveolar echinococcosis with a focus on pulmonary symptoms, emphasizing the importance of evaluation for pulmonary involvement in patients with AE and respiratory symptoms.

Basic Operative Tactics for Pulmonary Echinococcosis in the Era of Endostaplers and Energy Devices

Human echinococcosis is a zoonotic infection caused by the larvae of the tapeworm species Echinococcus. The liver is the most common location for a primary echinococcosis. However, the parasite may bypass or spread from the liver to the lungs, causing primary or secondary pulmonary echinococcosis, respectively. Pulmonary echinococcosis is a clinically challenging condition in which anthelminthic regiments are important, but surgery has the central role in removing the cysts and preventing recurrences. Surgical treatment may involve cystotomy, enucleation, capitonnage, or atypical resections, which occasionally are in combination with hepatic procedures. The utilization of modern devices is greatly underdescribed in surgery for thoracic infections, even though these facilitate much of the work. Therefore, this article aims to describe pulmonary echinococcosis and the role of modern surgical devices in the treatment process. Furthermore, we report surgical treatment of three different cases of pulmonary echinococcosis. Surgeries of uncomplicated and ruptured hepatic or pulmonary cysts are described. Simple small pulmonary echinococcal lesions can be excised by endostaplers both for diagnostic and curative reasons. Larger cysts can be removed by energy devices unless large bronchial air leaks occur. Complicated cysts require treatment by more extensive techniques. Inexperienced surgeons should not abstain but should carefully decide preoperatively how to proceed.

Massive sympathetic nerve infiltration in advanced hepatic alveolar echinococcosis: a case report and review of the literature

Background

Alveolar echinococcosis is a zoonotic disease that mostly affects the liver, with vascular invasion and a protean clinical symptom. However, no reports of sympathetic nerve infiltration in hepatic alveolar echinococcosis have been reported. Here, we report a case of hepatic alveolar echinococcosis in a 33-year-old man. In this end-stage case, the lesion was heavily involved in the large vessels and biliary tract, and immunohistochemistry also incidentally revealed extensive nerve infiltration in the specimens after surgical treatment. Subsequently, neural classification was identified.

Case presentation

We herein report a case of advanced hepatic alveolar echinococcosis with macrovascular invasion and sympathetic nerve infiltration. In this case, inferior vena cava (IVC), the portal vein and bile duct were infiltrated. Ultimately, according to our experience, ex vivo liver resection and autotransplantation (ELRA) was the optimal treatment way to perform for this unresectable patient. Samples were collected from normal liver tissue, junction tissue and the lesion. Hematoxylin–eosin (HE) staining was used to confirm the diagnosis. Neural infiltration was observed by immunohistochemical staining with protein gene product 9.5 (PGP9.5). Fluorescence colocalization was determined with PGP9.5 and tyrosine hydroxylase (TH). These results suggest that a large amount of sympathetic nerve infiltration occurred at the junction.

Conclusion

This study suggests that advanced hepatic alveolar echinococcosis shows infiltrating growth, often invades the large vessels and biliary ducts, and may be accompanied by sympathetic nerve infiltration.

Pulmonary hydatid cyst: Review of literature

Echinococcosis is a rare infectious disease in human being that occurs by the larval stages of taeniid cestodes of the genus Echinococcus. Human cystic echinococcosis is the most common presentation. The liver is the most common site of echinococcal cyst, followed by the lungs. The symptoms of lung infestation lead to sudden onset of chest pain, cough, fever, and hemoptysis after a cyst rupture. The diagnosis is confirmed by radiology supplemented with serology. Chest X-ray and computer tomography of chest is the principal investigation for pulmonary hydatid cyst (PHC). The treatment of PHCs is either pharmacotherapy and/or surgery. Surgical intervention is the most preferred treatment of choice; pharmacotherapy is useful in selected patients. Pharmacotherapy includes oral administration of benzimidazoles group of drugs like mebendazole or albendazole.