Hydatid lung disease (echinococcosis/hydatidosis)

More than 200 hydatid cysts in the lung with a large number of daughter cysts: A rare case report

INTRODUCTION AND IMPORTANCE

Hydatid cysts are a parasitic disease that occurs when humans ingest contaminated food or water containing parasitic eggs. It is a common disease worldwide, especially in cattle breeding areas. In rare cases, the primary cysts contain daughter cysts inside them, as seen in this case.

CASE PRESENTATION

We report a 28-year-old rural woman who presented with a history of sputum-producing cough, dyspnea, hemoptysis, and pain in the right side of the chest. The chest-abdomen-pelvis MSCT revealed a large number of cysts (more than 200 cysts) with daughter cysts inside them in the right lung and mediastinum. The cysts were surgically resected. After surgery, albendazole 200 mg twice a day was prescribed, with monitoring of liver function.

CLINICAL DISCUSSION

In the lungs, hydatid cysts are commonly found in the right lung (50 %), left lung (40 %), and may also be bilateral (10 %). The presence of multivesicular cysts in the lung is very rare. There are two hypotheses concerning the daughter cysts' formation. The first one suggests the effect of repeated mechanical trauma, while the other proposes the defensive mechanism of the patient. Diagnosis of the hydatid cysts in the lung is primarily through radiographic investigations such as Chest X-ray and CT scan. Surgery is still the main method to manage pulmonary hydatid cysts.

CONCLUSION

Although rare, multivesicular hydatid cysts in the lung should be considered, as they can mimic other diseases such as tumors and can cause an embolus in the pulmonary artery.

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.

Ruptured pulmonary hydatid cyst presenting as hemoptysis in TB endemic country: A case report

Introduction

Hydatid disease is a major zoonotic disease. After the liver, the lungs are the common site of involvement. Clinical manifestations of the disease depend on the site and size of the cysts as well as the presence of complications. The majority of the cases remain asymptomatic. Complicated pulmonary cysts can present as chest pain, cough, shortness of breath, and hemoptysis. Sometimes, imaging is not sufficient for diagnosis and histopathological evaluation can provide the confirmatory diagnosis.

Case presentation

A 32-year-old female presented with the complaints of episodic hemoptysis for the duration of two years. Radiological imaging could not provide a confirmatory diagnosis. Bronchoscopy was planned further. An endobronchial biopsy was taken for histopathological evaluation after seeing the whitish membranous structure within the right middle lobe bronchus. Hence, the diagnosis of ruptured cystic pulmonary hydatidosis was made.

Clinical discussion

Echinococcus granulosus is the cause of cystic pulmonary hydatid disease which is transmitted through contamination by the infected definitive host, mostly dogs. Most cases remain asymptomatic for a long period. Hydatid disease has many clinical and radiological forms which should be recognized and included in the differential diagnosis of many pulmonary problems. Sometimes, imaging and serological studies may not confirm the diagnosis, histopathological evaluation may be required.

Conclusion

Uncomplicated hydatid cysts are most commonly diagnosed incidentally in the adult population. Complicated hydatid cyst can present with various clinical manifestations. Episodic hemoptysis is one of the manifestations in our case. Clinicians should be aware of the typical as well as atypical manifestations of pulmonary hydatid disease.

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Ruptured pulmonary hydatid cyst usually presents with anaphylactic reaction but hemoptysis alone can be a presentation.

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Imaging and histologic findings help in confirming the diagnosis.

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Preventive educational program and early identification with atypical features are vital to prevent potential complications.

Insights into Human Cystic Echinococcosis in the Kurdistan Region, Iraq: Characteristics and Molecular Identification of Cysts

Cystic echinococcosis (CE) is a neglected worldwide distributed parasitic disease caused by the Echinococcusgranulosus sensu lato (s.l.) species complex. For a better understanding of the pathways of transmission of this parasite, clinical and molecular epidemiological studies are particularly needed from endemic areas where data are scant, such as in the Middle East. The study aimed to identify the characteristics, location, cyst stage and species/genotypes of E. granulosus s.l. complex in humans from the Kurdistan region, Iraq. To this aim, from June 2019 to February 2021, 64 echinococcal cysts were surgically removed from 62 patients in Azadi and Vajeen reference Hospitals at Duhok city, Duhok governorate (Kurdistan region, Iraq). The results confirmed the liver as the most common anatomical site of CE with 72.58% of the cases, followed by the lungs in 19.35%, while 66.13% of CE cases were females. The highest rate of infections occurred in the age class 21−30 (27.42%). High rates of CE were reported among patients living in rural areas and housewives, which were 54.84% and 43.55% of the CE patients, respectively. The fertility of echinococcal cysts was 82.81%, and the viability of fertile protoscoleces was 70.53%. Cysts were staged with ultrasound according to the WHO-IWGE classification as 32.8% CE1, 32.8% CE2, 7.8% CE3a, 9.4% CE3b, 15.6% CE4 and 1.6% CE5. Molecular analyses using mitochondrial NAD5 gene showed that all analyzed samples (n = 59) belonged to the genotypes G1 or G3 of E. granulosussensu stricto (s.s.), thus, confirming sheep−dog−human transmission in the Kurdistan region, Iraq. No statistically significant correlation was found between the genotypes G1−G3 of E. granulosus s.s. and variables, such as the fertility, location and cyst stage classification. Based on the present findings, it is necessary to implement monitoring and control programs in sheep and dog populations to decrease the odds of human infections. Public health education campaigns are required to be implemented at the community level to reduce the risk of acquiring CE in humans in the Kurdistan region, Iraq.

Flexible Fibreoptic Bronchoscopy and Bronchoalveolar Lavage for Confirmation of Pulmonary Hydatid Disease in Children: A Case Series

Hydatid disease of the lungs is common in endemic regions. It can be suspected clinically by non-specific respiratory symptoms in children living in endemic regions, especially when they are close to sheep or dogs. Chest imaging X-ray or computed tomography may show characteristic cysts in some cases, but typical findings are absent in many children. Hydatid serology may contribute to the diagnosis, but does not have sufficient sensitivity for pulmonary cysts. Thus, there is no confirmatory diagnostic test, other than surgical excision and histopathologic examination. Hence, there is a need for more reliable diagnostic tests. We present a series of children, both with and without suspected pulmonary hydatid, wherein flexible fibreoptic bronchoscopy (FFOB) performed under conscious sedation, revealed hydatid membranes in the airways. Bronchoalveolar lavage (BAL) analysis revealed hydatid in most of them. Thus the diagnosis could be confirmed even before surgical excision of cysts was performed. We propose that FFOB with BAL could be useful to confirm the diagnosis of pulmonary hydatid in children. This will be particularly helpful in children without characteristic radiological or serological findings. To the best of our knowledge, this is a completely novel approach to the condition with potential to alter the diagnostic paradigm Lay summary Hydatid disease of the lungs is commonly encountered in endemic regions. However, there is no confirmatory diagnostic test for pulmonary hydatid cyst, other than surgical excision and histopathologic examination. Imaging including chest X-ray and computed tomography may not be typical, especially in complicated cysts and hydatid serology does not have a satisfactory sensitivity for diagnosing lung cysts. Thus, there is a need for more reliable diagnostic tests. We present a series of children, both with and without suspected pulmonary hydatid, wherein flexible fibreoptic bronchoscopy (FFOB) under conscious sedation, revealed hydatid membranes in the airways. Bronchoalveolar lavage (BAL) analysis confirmed hydatid in most of them. We propose FFOB with BAL as a useful diagnostic modality to confirm pulmonary hydatid in children, prior to surgical excision. To the best of our knowledge, this is a completely novel approach to the condition with potential to alter the diagnostic paradigm.

Magnetic resonance imaging as an adjunct to computed tomography in the diagnosis of pulmonary Hydatid cysts

Introduction:

Although pulmonary hydatid cysts can be diagnosed on computed tomography (CT), sometimes findings can be atypical. Other hypodense infective or neoplastic lesions may mimic hydatid cysts. We proposed that magnetic resonance imaging (MRI) may act as a problem-solving tool, aiding the definite diagnosis of hydatid cysts and differentiating it from its mimics. The aim of this study is to assess the findings of pulmonary hydatid cysts on CT and MRI and the additional contribution of MRI in doubtful cases.

Materials and Methods:

This is a retrospective study of 90 patients with suspected hydatid cysts. CT and MRI findings were noted and role of MRI in diagnosing hydatid cysts and its mimics was studied. Descriptive statistics for CT findings and sensitivity and specificity of MRI were calculated using surgery or histopathology as gold standard.

Results:

Of the 90 patients with suspected pulmonary hydatid cysts, there were 52 true-positive and 7 false-positive cases on CT. Commonest CT finding was unilocular thick-walled cyst. In the 26 patients who had additional MRI, based on T2-weighted hypointense rim or folded membranes, accurate preoperative differentiation of 14 patients with hydatid cysts from 10 patients with alternate diagnosis was possible. There was one false-positive and one false-negative case on MRI.

Conclusion:

Although hydatid cyst can be diagnosed on CT on most occasions, sometimes there are challenges with certain mimics and atypical appearances. T2-weighted MRI can act as a problem solving tool to conclusively diagnose hydatid cyst or suggest an alternate diagnosis.

Pulmonary echinococcosis: A rare pseudotumour of the lung

Cystic echinococcosis is a widely endemic helminthic disease worldwide but occurs only rarely in Central Europe. Humans are infected as ‘aberrant’ hosts by Echinococcus granulosus and develop cysts in numerous different organs. 20%–30% of the affected individuals develop hydatid disease in the lungs with associated complications including pleuritis, lung abscess and pneumothorax. Radiologically, the pulmonary lesions of cystic echinococcosis occasionally pose difficulties in the differential diagnosis of primary lung carcinoma or metastatic disease and vice versa. Herein we report on a case of pulmonary hydatid disease in a 25-year-old Iraqi male presenting with a cystic lesion of the lung associated with thoracic pain and involuntary weight loss. Despite of its rare occurrence in Central Europe, clinicians, radiologists and pathologists should be aware of this entity and its pulmonary manifestations. During frozen section examination, imprint cytology specimens may facilitate the detection of the pathogens.

Application of Multi-Slice Computed Tomography for the Preoperative Diagnosis and Classification of Pulmonary Cystic Echinococcosis

Pulmonary cystic echinococcosis remains a serious threat to public health. A standardized, imaging-based classification method for pulmonary echinococcosis has not yet been developed despite the existence of a standardized ultrasound classification method and treatment plan for hepatic cystic echinococcosis. Chest computed tomography (CT) images from 34 cases of pulmonary cystic echinococcosis with 46 lesions were used for classification based on the World Health Organization (WHO) standardized ultrasound classification of hepatic cystic echinococcosis. CT findings were compared with intraoperative observations and postoperative pathological results to assess accuracy. Pulmonary cystic echinococcosis was common in women (14/34, 41.2%) and children (14/34, 41.2%) with a single cyst (28/46, 60.9%). Most lesions were classified as cystic echinococcosis 1(CE1, 19/46) or cystic echinococcosis 3(CE3, 21/46). Blood leukocytosis was mostly observed in CE3 lesions (100%, 9/9) (p < 0.05). The preoperative CT diagnosis of pulmonary cystic echinococcosis had an accuracy rate of 100%. The preoperative CT typing, and postoperative pathological typing had a coincidence rate of 97.8% (45/46). Our study provided a classification method based on CT imaging for pulmonary cystic echinococcosis that can be used during pre-surgical planning to reduce patient’s postoperative complications and mortality.

One-stage surgery for both hepatic and left ventricular hydatid cysts using transthoracic route

Hydatid disease is a major health problem. Multiorgan involvement including the heart and the liver is a very rare presentation. Management of multivisceral hydatidosis through a sole incision should be considered when possible. Median sternotomy is considered in our case.

Pulmonary Echinococcosis or Lung Hydatidosis: A Narrative Review

Background: Lung hydatidosis is a zoonosis related to infection by the Echinococcus tapeworm species. Lung involvement in this condition is second only to the liver echinococcosis. Diagnosis ordinarily results from an accidental finding in a direct chest radiograph evaluation because of the delayed growth of the cysts. Moreover, a consistent treatment regimen or approach may not be feasible because of the variability of pulmonary echinococcosis. In this review, we expect to sum up the main features of lung hydatidosis with a perspective on medical and surgical treatment. Methods: Cochrane Library and PubMed were the databases used to perform a narrative literature review. Search terms included "pulmonary echinococcosis" and "lung hydatidosis." The MeSH terms were "lung" [All Fields] AND {"echinococcosis" [MeSH Terms] OR ("hydatidosis" [All Fields] OR "pulmonary" [All Fields] AND "echinococcosis" [All Fields] OR "hydatidosis." A search period from September 1980 to May 2020 was chosen to compare studies from different decades, given the changes in pulmonary echinococcosis management. Results: A uniform treatment regimen or approach may not be feasible because of the variability of pulmonary echinococcosis. No clinical trials have analyzed and compared all the diverse treatment approaches. Cyst size, characteristics, position in the lung and clinical presentation, and the availability of medical/surgical expertise and equipment are the mainstays of echinococcosis management. When feasible, surgery is as yet the principal therapeutic choice to eliminate the cysts; anti-parasitic drugs may minimize complications during high-risk surgery or be used as definitive therapy in some instances with contraindications to surgery. Conclusions: Lung hydatidosis management must become less heterogeneous. We support treatment directed to the subject established on the clinical scenario, host factors, and surgical risk. Strict cooperation in this process between infectious disease specialists and surgeons may optimize best practices to help create shared practical guidelines to simplify clinicians' decision-making. Furthermore, we need a consensus for lung hydatidosis treatment and inserting this disease to global surgery agenda will have a positive impact on acquiring high-quality data that enables us to create an evidence-based guideline for this disease.

Radiological manifestations of thoracic hydatid cysts: pulmonary and extrapulmonary findings

Hydatid cyst caused by the larval form of Echinococcus is a worldwide zoonosis. The lungs and liver are the most common sites involved. While the lung parenchyma is the most common site within the thorax, it may develop in any extrapulmonary region including the pleural cavity, fissures, mediastinum, heart, vascular structures, chest wall, and diaphragm. Imaging plays a pivotal role not only in the diagnosis of hydatid cyst, but also in the visualization of the extent of involvement and complications. The aim of this pictorial review was to comprehensively describe the imaging findings of thoracic hydatid cyst including pulmonary and very unusual extrapulmonary involvements. An outline is also given for the findings of complications and differential diagnosis of thoracic hydatid cyst.

Primary pulmonary cystic Echinococcus in an immunocompetent patient

A 60-year-old man was referred to the interventional pulmonology clinic with a large right-sided intraparenchymal lung mass and a second, smaller lesion in the left lower lobe, accompanied by intermittent haemoptysis, fever, chills, productive cough of white phlegm as well as dizziness and weakness. He had presented previously and was being evaluated for the possibility of malignancy. Investigations had revealed 'hooklets' (protoscolices) of hydatid cysts, most likely representing the parasite Echinococcus Successful surgical excision of the affected lobe, lung decortication, partial pleurectomy and pneumolysis of the adhesions was performed, along with long-term antiparasitic therapy. The initial differential diagnosis for this patient was challenging and required multimodal investigations. The patient made good recovery and continued to be followed by infectious disease specialists for management of antiparasitic therapy.

A Comparative Study of Different Immunoassays to Detect Specific Antibodies to Echinococcus Spp. in Human Sera

Human echinococcosis, one of the most serious of parasitic zoonoses, is caused by the larval stages of taeniid cestodes of the genus Echinococcus. The study aimed to assess the reliability of the detection of specific antibodies to E. multilocularis and E. granulosus s.l. in human sera and to compare their diagnostic potential for their utilization in the practice. In the study, the somatic antigen of E. multilocularis (AgEm), antigen B (AgB), and the hydatid fluid antigen of E. granulosus and two commercial ELISA kits – Echinococcus granulosus (Bordier Affinity Products, Crissier, Switzerland) and NovaLisa^TMEchinococcus IgG (NovaTec Immunodiagnostica, Germany) – were compared. Sera of patients with alveolar and cystic echinococcosis, and with different parasitic/other infections were used to evaluate the sensitivity, specificity and cross-reactivity of in-house and commercial ELISA methods. AgEm presented the highest values regarding the diagnostic indicators, showing 100 % specificity and 90.0 % sensitivity. The tests for serological diagnostics of cystic echinococcosis were less sensitive and specific. The Echinococcus granulosus kit had 83.8 % specificity and 88.2 % sensitivity, while AgB and AgHF showed 85.0 % and 86.3 % specificity, and 76.5 % and 100 % sensitivity, respectively. NovaLisa^TMEchinococcus IgG proved to have 95.7 % specificity and 77.8 % sensitivity. The results point out that the combination of different serological tests and approaches in accordance with clinical and imaging findings is still essential to prove the correct diagnosis in suspected patients.

Pleuritic chest pain in a young asylum seeker

A 17-year-old asylum seeker from Afghanistan presented to the emergency department with chest pain. He had travelled to the UK after residing in multiple European cities. He presented with a 1-week history of right-sided pleuritic chest pain. There was no evidence of a productive cough or recent viral illness and he had no history of injury to the chest. In addition to his chest pain, he had been suffering from persistent right upper quadrant discomfort for approximately 3 years. There was no nausea or vomiting and he denied any bowel or urinary symptoms. He had experienced episodes of fever and loss of appetite but no change in weight. His past medical background consisted of black water fever, as a consequence of malaria, and a previous gunshot wound, which had now healed. He took no regular medications and all of his clinical observations were stable at the time of presentation.

It is important to note that a negative serological test result does not exclude a diagnosis of cystic Echinococcus, particularly in cases of extra hepatic diseasehttp://bit.ly/2JRAk6H

Infectious Lung Disease

Infectious diseases are one of the main causes of morbidity and mortality worldwide. With new pathogens continuously emerging, known infectious diseases reemerging, increasing microbial resistance to antimicrobial agents, global environmental change, ease of world travel, and an increasing immunosuppressed population, recognition of infectious diseases plays an ever-important role in surgical pathology. This becomes particularly significant in cases where infectious disease is not suspected clinically and the initial diagnostic workup fails to include samples for culture. As such, it is not uncommon that a lung biopsy becomes the only material available in the diagnostic process of an infectious disease. Once the infectious nature of the pathological process is established, careful search for the causative agent is advised. This can often be achieved by examination of the hematoxylin and eosin-stained sections alone as many organisms or their cytopathic effects are visible on routine staining. However, ancillary studies such as histochemical stains, immunohistochemistry, in situ hybridization, or molecular techniques may be needed to identify the organism in tissue sections or for further characterization, such as speciation.

"Necklace in the lung:" Multilocularis hydatid cyst mimicking left-sided massive pleural effusion

Massive pleural effusions are commonly caused by malignancy, parapneumonic effusion, and tuberculosis. Parasitic infections are rare causes of massive pleural effusion. Echinococcosis or hydatid disease is a major public health problem in poor hygienic environments. The liver and lungs are the most frequently involved organs. Pulmonary disease appears to be more common in younger individuals. Echinococcus multilocularis causes alveolar echinococcosis, which accounts for <5% of all cases of hydatid liver disease and less frequently lung disease. Here, we present an unusual case of multilocular pulmonary hydatid cysts mimicking massive pleural effusion in a 25-year-old young male.

A Case of Echinococcal Cyst of the Lung

Echinococcosis, also known as Hydatid disease, is caused by the larvae of the tapeworm Echinococcus. It is globally prevalent and is a major clinical health concern. It is endemic in most underdeveloped regions including Asia, the Mediterranean, South America and Africa. There are four species within the genus Echinococcus, with E. granulosus and E. multilocularis being the most common, causing Cystic Echinococcosis (CE) and Alveolar Echinococcosis (AE). The clinical presentation of the disease is non-specific. It commonly involves the liver, lungs, brain and adrenal glands. Pulmonary disease is significant for its propensity to affect children and young adults. This young population accounts for ∼50% of pulmonary hydatid cysts [1]. Cysts are known to grow extensively in size. Many patients are asymptomatic and have only a solitary cyst. Symptoms arise from enlargement of the cyst and from eroding and pressure applied by the cyst to blood vessels and organs. If rupture of the cyst occurs it can lead to immunologic reactions such as asthma and anaphylaxis. Echinococcus in the lung can pose diagnostic dilemmas, as their homogeneous density and tendency to occur alone may cause them to be confused with squamous cell carcinoma, adenocarcinoma, solitary metastasis, and abscess [2]. Our case is of such a patient who was found to have a 6 cm mass in the right middle lobe (RML) found on a chest X-ray during evaluation of back pain. Echinococcus should always be included in a differential diagnosis of any mass lesions especially in immigrant populations from endemic countries.

Echinococcosis mimicking liver malignancy: A case report

INTRODUCTION

Human Alveolar Echinococcosis - Alveolar Hydatid disease (AE) is an omitted zoonotic infection presenting with focal liver lesions. Cause of AE is a larval stage of Echinococcus multilocularis tapeworms.

CASE PRESENTATION

In this report an extraordinary case of a 38 year-old female examined due to 2 liver tumors and 2 pulmonary nodules is described. The patient underwent pulmonary and liver surgery for suspected advanced cholangiocellular carcinoma and surprisingly AE was found.

DISCUSSION

Distinguishing intrahepatic AE from other focal liver lesion can be complicated and in many cases is diagnosed incorrectly as intrahepatic cholangiocarcinoma or other liver malignancy.

CONCLUSION

AE is a rare but potentially fatal parasitic infection primarily affecting liver, although it can metastasise to lung, brain and other organs. The diagnosis and treatment can be difficult and clinical misinterpretation as malignancy is not rare. The principal treatment of AE is surgery accompanied with chemotherapy.

Seronegative, complicated hydatid cyst of the lung: A case report

Cystic echinococcosis (CE) is an important helminthic zoonotic disease that commonly affects the liver and lungs. Imaging methods and serology establish the diagnosis in most cases. Chest x-ray can diagnose uncomplicated pulmonary hydatid cysts, whereas superinfection and/or rupture of the hydatid cyst (complicated cysts) may change the radiographic appearance and lead to delayed diagnosis and treatment. We report the case of a patient with hemoptysis and chest pain, where computer tomography scan of the lung suggested a large, ruptured hydatid cyst. However, serological tests with indirect hemagglutination (IHA)for Echinococcus granulosus antibodies were negative, and there was massive growth of Streptococcus pneumoniae in sputum. Based on this, we concluded that the patient had a bacterial lung abscess. The diagnosis of CE was only made after surgical removal of the cyst followed by microscopy and polymerase chain reaction.

Cystic pulmonary hydatidosis

Cystic echinococcosis (CE) is a zoonotic parasitic disease caused by the larval stages of the cestode Echinococcus granulosus. Worldwide, pulmonary hydatid cyst is a significant problem medically, socially, and economically. Surgery is the definitive therapy of pulmonary hydatidosis. Benzimidazoles may be considered in patients with a surgical contraindication. This review will focus on pathogenesis, lifecycle, clinical features, and management of pulmonary hydatid disease.

Middle lobe syndrome: a singularly rare presentation of complicated pulmonary hydatid disease

Imaging is crucial to the diagnosis of pulmonary hydatid disease, as it is often the first modality that raises suspicion of the disease. Middle lobe syndrome (MLS) as a presentation of this disease is a distinct rarity. A 45-year-old woman, a never-smoker, presented with cough and streaky haemoptysis. Imaging demonstrated a trapezoidal opacity with its base towards the hilum and contiguous with the right cardiac border. The reformatted sagittal view confirmed the diagnosis of MLS. Fibreoptic bronchoscopy (FOB) revealed an avascular white membranous structure wholly occluding the medial segment of the middle lobe. This was completely removed through gentle suction. Bronchial aspirate revealed hooklets of hydatid and echinococcal serology was positive. Subsequently, three cycles of albendazole were administered with remarkable clinical and radiological improvement. To the best of our knowledge, this is the first detailed description of MLS caused by pulmonary hydatidosis that was completely removed through FOB.

Parasitic pneumonia and lung involvement

Parasitic infestations demonstrated a decline in the past decade as a result of better hygiene practices and improved socioeconomic conditions. Nevertheless, global immigration, increased numbers of the immunocompromised people, international traveling, global warming, and rapid urbanization of the cities have increased the susceptibility of the world population to parasitic diseases. A number of new human parasites, such as Plasmodium knowlesi, in addition to many potential parasites, have urged the interest of scientific community. A broad spectrum of protozoal parasites frequently affects the respiratory system, particularly the lungs. The diagnosis of parasitic diseases of airway is challenging due to their wide varieties of clinical and roentgenographic presentations. So detailed interrogations of travel history to endemic areas are critical for clinicians or pulmonologists to manage this entity. The migrating adult worms can cause mechanical airway obstruction, while the larvae can cause airway inflammation. This paper provides a comprehensive review of both protozoal and helminthic infestations that affect the airway system, particularly the lungs, including clinical and roentgenographic presentations, diagnostic tests, and therapeutic approaches.

[Multiple extrapulmonary thoracic hydatidosis]

INTRODUCTION

Extrapulmonary intrathoracic hydatid cysts are unusual but they may be multiple, particularly during a secondary dissemination. With the aim to clarify the origins of this dissemination, we report our experience in the treatment of multiple thoracic extrapulmonary hydatidosis (MTEH).

MATERIAL AND METHODS

Between January 1995 and December 2004, 41 patients were operated on for MTEH in our department. Chest roentgenogram and computed tomography were the main means of diagnosis. The treatment consisted of total surgical removal of the intact cysts. The approach was a postero-lateral thoracotomy (right in 29 cases, left in 8 cases, bilateral in 3 cases) and a median sternotomy in one case. All patients received complementary medical treatment with Albendazol.

RESULTS

The MTEH was secondary to haematogenous dissemination in 6 patients (15%), to a hydatid cyst of the lung in 7 patients (17%) and to a hydatid cyst of the liver in 28 patients (68%). 75% of these patients had had a previous surgical intervention for hepatic cyst and 88% of them had diaphragm involvement. There were no deaths among our patients but the recurrence rate was 12%.

CONCLUSION

Secondary intrathoracic extrapulmonary hydatidosis is generally seen among patients operated on for hydatid cyst of the liver. Necessary precautions must be taken at the time of surgery to avoid any intrathoracic dissemination.

Eosinophilia in returning travelers and migrants

INTRODUCTION

Eosinophilia in travelers returning from tropical countries is often caused by helminths. The high eosinophil counts arise particularly from tissue migration of invasive larvae.

METHODS

Review of literature selected by means of a Medline search using the MeSH terms "eosinophilia" and "helminth."

RESULTS

The patient's geographic and alimentary history may suggest infection with particular parasitic worms. A targeted diagnostic approach is suggested. The physician should concentrate on the principal signs and be guided by the geographic and alimentary history. Elaborate diagnostic measures are seldom indicated.

DISCUSSION

Although eosinophilia alone has low positive predictive value for a worm infection, it points clearly to helminthosis if the patient has recently returned from the tropics and the eosinophilia is new.

Cavitary pulmonary disease

A pulmonary cavity is a gas-filled area of the lung in the center of a nodule or area of consolidation and may be clinically observed by use of plain chest radiography or computed tomography. Cavities are present in a wide variety of infectious and noninfectious processes. This review discusses the differential diagnosis of pathological processes associated with lung cavities, focusing on infections associated with lung cavities. The goal is to provide the clinician and clinical microbiologist with an overview of the diseases most commonly associated with lung cavities, with attention to the epidemiology and clinical characteristics of the host.

Imaging of Parasitic Diseases of the Thorax

A broad spectrum of parasitic infections frequently affects the lungs, mediastinum, and thoracic wall, manifesting with abnormal imaging findings that often make diagnosis challenging. Although most of these infections result in nonspecific abnormalities, familiarity with their imaging features and the diagnostic pathways help the radiologist to formulate an adequate differential diagnosis and to guide diagnosticians in reaching a definitive diagnosis.

Parasitic diseases of the respiratory tract

PURPOSE OF REVIEW

The human pulmonary system can be affected by a variety of parasites. This review focuses on the most common parasitic infestations involving the lung, except for protozoon disease.

RECENT FINDINGS

In many parasitic lung conditions, the clinical manifestations and the imaging findings are non-specific and can make diagnosis challenging. Hydatid disease and paragonimiasis involve the lung directly. Chronic schistosomiasis can lead to pulmonary hypertension. Strongyloides stercoralis infestation is capable of transforming into a fulminant fatal disease. In many types of nematode infestations, the pulmonary phase can cause acute eosinophilic pneumonia. Chest radiographs of patients with paragonimiasis and dirofilariasis can cause diagnostic confusion. Cases of tropical pulmonary eosinophilia typically present with refractory bronchial asthma. Most of these diseases are initially diagnosed by detecting eggs or larvae in stool, sputum, pleural fluid or tissue, and are confirmed by serologic testing. Cystic hydatid disease generally requires surgical treatment, whereas almost all other parasitic lung conditions can be treated medically.

SUMMARY

Although most parasites that affect the lung are endemic to tropical and subtropical regions, immigration and travel practices have resulted in transfer of these diseases to other areas. It is important for physicians to know the epidemiologic characteristics, clinical presentations, and treatments of choice for these conditions.

Neuroparasitic infections: cestodes, trematodes, and protozoans

Parasitic infection of the nervous system can produce a variety of symptoms and signs. Because symptoms of infection are often mild or nonspecific, diagnosis can be difficult. Familiarity with basic epidemiological characteristics and distinguishing radiographic findings can increase the likelihood of detection and proper treatment of parasitic infection of the nervous system. This article discusses the clinical presentation, diagnosis, and treatment for some of the more common infections of the nervous system caused by cestodes, trematodes and protozoans: Echinococcus spp., Spirometra spp. (sparganosis), Paragonimus spp., Schistosoma spp., Trypanosoma spp., Naegleria fowlerii, Acanthamoeba histolytica, and Balamuthia mandrillaris.

[Complete extraction of a hydatid membrane by bronchial fibroscopy]

Pulmonary hydatid cyst is exceptional in our country. The diagnosis is generally established on the basis of imaging. Surgical treatment is indicated in most patients. We report a case of pulmonary hydatid cyst in a 74-year-old smoker (11 package-years) who presented cough with mucopurulent expectoration and occasional hemoptysis. The chest x-ray demonstrated a poorly delimited heterogeneous opacity in the upper third of the left lung which persisted after antibiotic therapy. Bronchial fibroscopy revealed a hydatid membrane in the left superior bronchus which was totally removed by aspiration. A control radiography after the fibroscopy demonstrated a clear regression of the opacity. A thoracic CT-scan was performed and revealed a residual cavity in the left upper lobe with bronchial dilatation. The indication for surgery was not retained. Treatment of pulmonary hydatid cyst by endoscopy is an exceptional event. Our exceptional case illustrates an atypical radiological presentation and the use of "therapeutic" fibroscopy.

Thoracic Manifestations of Tropical Parasitic Infections: A Pictorial Review

Parasitic infections are distributed worldwide and affect hundreds of millions of individuals-primarily those living in endemic areas or in regions with a high rate of immigration from endemic areas-causing significant morbidity and mortality. A broad spectrum of parasitic infections (eg, amebiasis, malaria, trypanosomiasis, ascariasis, strongyloidiasis, dirofilariasis, cystic echinococcosis, schistosomiasis, paragonimiasis) frequently affect the lungs, mediastinum, and thoracic wall, manifesting with abnormal imaging findings that often make diagnosis challenging. Although most of these infections result in nonspecific abnormalities, familiarity with their imaging features as well as their epidemiologic, clinical, and physiopathologic characteristics may be helpful to the radiologist in formulating an adequate differential diagnosis.

Epidemiology, clinical manifestations and diagnosis of zoonotic cestode infections: an update

This paper reviews the literature on zoonotic cestode infections with specific reference to the years 1999-2003. The sources and prevalence of various zoonotic tapeworm infections caused by adult and larval stages of the genera Taenia, Echinococcus, Diphyllobothrium, Hymenolepis and Dipylidium continue to be an important cause of morbidity and mortality, not only in most underdeveloped countries but also in industrialized countries, particularly in rural areas or among immigrant groups from endemic areas. The review gives a detailed report on recent molecular epidemiological studies on the taxonomy and phylogenetic variations in Echinococcus granulosus, immunological tests and imaging techniques used in epidemiological surveys and clinical investigations of important adult and larval tapeworm infections of animals and humans. Larval stages or metacestodes of Taenia solium, Echinococcus spp. and pseudophyllidean tapeworms (Spirometra syn. Diphyllobothrium spp.) may reside in various tissues of their intermediate hosts, including humans. In particular, Cysticercus cellulosae (T. solium) and the larvae of E. granulosus, and E. multilocularis, which are predominantly located in the liver, lungs and central nervous system forming various types of cysts, lead to a complex of systemic diseases such as cysticercosis, cystic echinococcosis and alveolar echinococcosis, respectively. Relatively rare clinical manifestations are seen in the muscles, subcutaneous tissue, spleen, kidneys, bones and body cavities.

The crystal structure of Echinococcus granulosus fatty-acid-binding protein 1

We describe the 1.6 A crystal structure of the fatty-acid-binding protein EgFABP1 from the parasitic platyhelminth Echinococcus granulosus. E. granulosus causes hydatid disease, which is a major zoonosis. EgFABP1 has been implicated in the acquisition, storage, and transport of lipids, and may be important to the organism since it is incapable of synthesising most of its lipids de novo. Moreover, EgFABP1 is a promising candidate for a vaccine against hydatid disease. The crystal structure reveals that EgFABP1 has the expected 10-stranded beta-barrel fold typical of the family of intracellular lipid-binding proteins, and that it is structurally most similar to P2 myelin protein. We describe the comparison of the crystal structure of EgFABP1 with these proteins and with an older homology model for EgFABP1. The electron density reveals the presence of a bound ligand inside the cavity, which we have interpreted as palmitic acid. The carboxylate group of the fatty acid interacts with the protein's P2 motif, consisting of a conserved triad R em leader R-x-Y. The hydrophobic tail of the ligand assumes a fairly flat, U-shaped conformation and has relatively few interactions with the protein.We discuss some of the structural implications of the crystal structure of EgFABP1 for related platyhelminthic FABPs.