Giant hydatid lung cysts in the Canadian northwest: outcome of conservative treatment in three children

Trust the Capitonnage in the Giant Cyst: Case Report

Cyst hydatid in the lung is still a health problem for many countries. It develops in the lung and can grow into the lung parenchyma. When it is diagnosed as a giant cyst, surgery should be performed. In the surgery, capitonnage is necessary to protect the lung parenchyma.

Global Distribution of Alveolar and Cystic Echinococcosis

Alveolar echinococcosis (AE) and cystic echinococcosis (CE) are severe helminthic zoonoses. Echinococcus multilocularis (causative agent of AE) is widely distributed in the northern hemisphere where it is typically maintained in a wild animal cycle including canids as definitive hosts and rodents as intermediate hosts. The species Echinococcus granulosus, Echinococcus ortleppi, Echinococcus canadensis and Echinococcus intermedius are the causative agents of CE with a worldwide distribution and a highly variable human disease burden in the different endemic areas depending upon human behavioural risk factors, the diversity and ecology of animal host assemblages and the genetic diversity within Echinococcus species which differ in their zoonotic potential and pathogenicity. Both AE and CE are regarded as neglected zoonoses, with a higher overall burden of disease for CE due to its global distribution and high regional prevalence, but a higher pathogenicity and case fatality rate for AE, especially in Asia. Over the past two decades, numerous studies have addressed the epidemiology and distribution of these Echinococcus species worldwide, resulting in better-defined boundaries of the endemic areas. This chapter presents the global distribution of Echinococcus species and human AE and CE in maps and summarizes the global data on host assemblages, transmission, prevalence in animal definitive hosts, incidence in people and molecular epidemiology.

Cystic echinococcosis: Future perspectives of molecular epidemiology

Human cystic echinococcosis (CE) has been considered to be caused predominantly by Echinococcus granulosus sensu stricto (the dog-sheep strain). Molecular approaches on CE, however, have revealed that human cases are also commonly caused by another species, Echinococcus canadensis. All indices for classification and standardization of CE pathology including available images, epidemiology, diagnostics and treatment are currently based largely on a mixture of infections which include at least E. granulosus s.s. and E. canadensis. Involvement of other species of Echinococcus in CE including E. ortleppi or otherwise cryptic diversity demonstrated recently in Africa requires further elucidation. Molecular identification of the causative species in CE cases is essential for better understanding of pathogenesis and disease. This article stresses the importance of molecular species identification of human CE as a foundation for re-evaluation of evidence-based epidemiology.

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.

An autochthonous case of cystic echinococcosis in Finland, 2015

We report a case of pulmonary cystic echinococcosis in a child from eastern Finland with no history of travelling abroad. The cyst was surgically removed and the organism molecularly identified as Echinococcus canadensis genotype G10. This parasite is maintained in eastern Finland in a sylvatic life cycle involving wolves and moose; in the present case, the infection was presumably transmitted by hunting dogs.

The present situation of echinococcoses in Mongolia

This review presents the historical and current situation of echinococcoses in Mongolia. Since the collapse of the Soviet Union in 1991, Mongolia's health surveillance infrastructure has been very poor, especially as it pertains to chronic diseases, including neglected zoonotic diseases (NZDs). Although there is anecdotal evidence of people dying from hepatic disease due to infection with the larval stage of Echinococcus spp., there are very few published reports. All confirmed cases of echinococcoses in Mongolia are from hospitals located in the capital city of Ulaanbaatar. Cases of cystic echinococcosis (CE), caused by either Echinococcus granulosus sensu stricto or Echinococcus canadensis are believed to be relatively common throughout Mongolia. In contrast, cases of alveolar echinococcosis (AE), caused by Echinococcus multilocularis, are believed to be rare. Recent wild-animal surveys have revealed that wolves (Canis lupus) are the major definitive hosts of E. canadensis, whereas both wolves and red foxes (Vulpes vulpes) are the primary definitive hosts of E. multilocularis. Although wild-animal surveys have begun to elucidate the transmission of Echinococcus spp. in Mongolia, there have yet to be large-scale studies conducted in domestic dogs and livestock. Therefore, further epidemiological studies, in addition to education-based control campaigns, are needed to help combat this NZD.

Echinococcosis: An Economic Evaluation of a Veterinary Public Health Intervention in Rural Canada

Echinococcosis is a rare but endemic condition in people in Canada, caused by a zoonotic cestode for which the source of human infection is ingestion of parasite eggs shed by canids. The objectives of this study were to identify risk factors associated with infection and to measure the cost-utility of introducing an echinococcosis prevention program in a rural area. We analyzed human case reports submitted to the Canadian Institutes for Health Information between 2002 and 2011. Over this 10 year period, there were 48 cases associated with E. granulosus/E. canadensis, 16 with E. multilocularis, and 251 cases of echinococcosis for which species was not identified (total 315 cases). Nationally, annual incidence of echinococcosis was 0.14 cases per 100 000 people, which is likely an underestimate due to under-diagnosis and under-reporting. Risk factors for echinococcosis included female gender, age (>65 years), and residing in one of the northern territories (Nunavut, Yukon, or Northwest Territories). The average cost of treating a case of cystic echinococcosis in Canada was $8,842 CAD. Cost-utility analysis revealed that dosing dogs with praziquantel (a cestocide) at six week intervals to control cystic echinococcosis is not currently cost-effective at a threshold of $20,000-100,000 per Quality Adjusted Life Year (QALY) gained, even in a health region with the highest incidence rate in Canada ($666,978 -755,051 per QALY gained). However, threshold analysis demonstrated that the program may become cost-saving at an echinococcosis incidence of 13-85 cases per 100,000 people and therefore, even one additional CE case in a community of 9000 people could result in the monetary benefits of the program outweighing costs.

In Canada, Echinococcus spp. tapeworms cycle primarily among wildlife hosts. People are infected with this parasite when they accidentally consume microscopic eggs spread by canids (e.g. dogs, wolves, coyotes, and foxes), and develop larval cysts, often in the liver or lungs. Echinococcosis can be a life-threatening medical condition with long-term health consequences and can be an economic burden for infected individuals and for the public health system. We analysed national health records to measure echinococcosis incidence and risk factors in Canada, and then used this information to determine if a program that facilitated dog deworming to prevent human infection might be economically feasible. Our model suggested that treating infected individuals is currently less expensive than preventing infection, even in the highest risk regions of Canada. However, deworming dogs might be feasible in small rural communities where at least one case was identified. Furthermore, the prevention program has many add-on benefits that contribute to overall community health, but are not measured by our model.

Parasite prevalence in fecal samples from shelter dogs and cats across the Canadian provinces

BACKGROUND

In Canada, surveys of enteric parasites in dogs and cats have been reported sporadically over the past 40 years, mostly focusing on a specific region. The present work was performed to determine the current prevalence of various parasites in fecal samples from shelter dogs and cats across the Canadian provinces.

METHODS

A total of 1086 dog and 636 cat fecal samples from 26 shelters were analysed using a sugar solution double centrifugal flotation technique. Prevalences (national, regional, provincial, age and parasite-specific), were calculated and compared using the Fisher-Exact test. A multiplex PCR was performed to distinguish Taenia spp, Echinococcus granulosus and E. multilocularis on samples positive for taeniid eggs.

RESULTS

Overall, 33.9% of dogs and 31.8% of cats were positive for at least one parasite. Toxocara canis and T. cati were the most prevalent parasite present in fecal samples followed by Cystoisospora spp. Prevalence in dogs was similar across the Atlantic, East, West and Pacific regions, while prevalence in cats varied regionally. Eggs of E. granulosus/E. canadensis were detected in samples from dogs from BC, AB, and ON.

CONCLUSIONS

Data from this study will help in the development of strategies, based on the level of risk per geographic location for the prevention and response to these parasites in pets and free-roaming and shelter animals in Canada.

Tradition and transition: parasitic zoonoses of people and animals in Alaska, northern Canada, and Greenland

Zoonotic parasites are important causes of endemic and emerging human disease in northern North America and Greenland (the North), where prevalence of some parasites is higher than in the general North American population. The North today is in transition, facing increased resource extraction, globalisation of trade and travel, and rapid and accelerating environmental change. This comprehensive review addresses the diversity, distribution, ecology, epidemiology, and significance of nine zoonotic parasites in animal and human populations in the North. Based on a qualitative risk assessment with criteria heavily weighted for human health, these zoonotic parasites are ranked, in the order of decreasing importance, as follows: Echinococcus multilocularis, Toxoplasma gondii, Trichinella and Giardia, Echinococcus granulosus/canadensis and Cryptosporidium, Toxocara, anisakid nematodes, and diphyllobothriid cestodes. Recent and future trends in the importance of these parasites for human health in the North are explored. For example, the incidence of human exposure to endemic helminth zoonoses (e.g. Diphyllobothrium, Trichinella, and Echinococcus) appears to be declining, while water-borne protozoans such as Giardia, Cryptosporidium, and Toxoplasma may be emerging causes of human disease in a warming North. Parasites that undergo temperature-dependent development in the environment (such as Toxoplasma, ascarid and anisakid nematodes, and diphyllobothriid cestodes) will likely undergo accelerated development in endemic areas and temperate-adapted strains/species will move north, resulting in faunal shifts. Food-borne pathogens (e.g. Trichinella, Toxoplasma, anisakid nematodes, and diphyllobothriid cestodes) may be increasingly important as animal products are exported from the North and tourists, workers, and domestic animals enter the North. Finally, key needs are identified to better assess and mitigate risks associated with zoonotic parasites, including enhanced surveillance in animals and people, detection methods, and delivery and evaluation of veterinary and public health services.

Worldwide epidemiology of liver hydatidosis including the Mediterranean area

The worldwide incidence and prevalence of cystic echinococcosis have fallen dramatically over the past several decades. Nonetheless, infection with Echinococcus granulosus (E. granulosus) remains a major public health issue in several countries and regions, even in places where it was previously at low levels, as a result of a reduction of control programmes due to economic problems and lack of resources. Geographic distribution differs by country and region depending on the presence in that country of large numbers of nomadic or semi-nomadic sheep and goat flocks that represent the intermediate host of the parasite, and their close contact with the final host, the dog, which mostly provides the transmission of infection to humans. The greatest prevalence of cystic echinococcosis in human and animal hosts is found in countries of the temperate zones, including several parts of Eurasia (the Mediterranean regions, southern and central parts of Russia, central Asia, China), Australia, some parts of America (especially South America) and north and east Africa. Echinococcosis is currently considered an endemic zoonotic disease in the Mediterranean region. The most frequent strain associated with human cystic echinococcosis appears to be the common sheep strain (G1). This strain appears to be widely distributed in all continents. The purpose of this review is to examine the distribution of E. granulosus and the epidemiology of a re-emerging disease such as cystic echinococcosis.

Lung hydatic cysts in children: comparison study between giant and non-giant cysts

PURPOSE

The aim of this study is to review our experience in pediatric giant pulmonary hydatid cysts focusing on clinical symptoms, location of the cyst, type of the intervention, postoperative complications and long-term results.

METHODS

Between June 2002 and May 2007, 118 children were operated on for hydatid lung cysts. Two groups were defined: Group 1, 32 children with giant hydatid cysts and Group 2, 86 children with non-giant cysts. The statistical significance between the groups was estimated using paired samples t test.

RESULTS

The mean age was 11.8 years in G1 and 9.7 years in G2. All of the patients were symptomatic in G1 but only 18% in G2 (P=0.003). The right lower lobe was most frequently involved in both G1 and G2. Surgical parenchymal resection was performed in five patients in G1 (16%) and in 2% in G2 (P=0.033). Postoperative complications in G1 were more significant comparatively to G2 (P=0.003).

CONCLUSION

Giant hydatid lung cysts represent a distinct pathology. They affect essentially adolescents and may reach a large size causing parenchymal destruction. Thus, surgical resections are frequently used and postoperative complications rate is high.

Infections in the natural environment of British Columbia, Canada

The Canadian province of British Columbia has a luxurious environment, complete with the multitude of wildlife and insects, and would at first glance appear to be suitable for the transmission of diseases in nature communicable to humans. Despite this potential, such diseases are relatively uncommon, although several have the potential for serious consequences. Attention has been recently focused on hantavirus infection, water-borne toxoplasmosis and parasitic diarrheal diseases, cryptococcosis on Vancouver Island, and rabies. West Nile virus has not yet caused endemic human infection in this province as of 2008. We review the cumulative science in this area.

Cystic echinococcosis in the Americas

Echinococcus granulosus and related genotypic variants, the agents of cystic hydatid disease, occur widely in the American continents from Alaska and Northern Canada in North America to Tierra del Fuego in South America. Here we review the historical and current distribution and prevalence of these infections throughout the American countries and the results of programs to control or eliminate the infection.

Primary pulmonary hydatid cysts in children-a report of three cases

Three children with a total of six primary pulmonary hydatid cysts, all of whom underwent surgical management, are presented. Of these six hydatid cysts, two were treated with thoracotomy with cyst enucleation and capittonage, three with thoracoscopy-assisted minithoracotomy with enucleation and capittonage, and one with limited resection.

Atypical pulmonary giant hydatid cyst as bilaterally symmetrical solitary cysts

A pulmonary giant hydatid cyst, a special clinical entity, is rare. Our case involves a young patient who presented with a bilaterally symmetrical solitary cyst in each lung, a feature consistent with congenital lung cysts. The radiological and immunological findings were equivocal. A diagnosis of giant hydatid cyst was made intraoperatively and both cysts were removed conservatively. A follow-up showed complete recovery.

Accidental drainage of a cerebral hydatid cyst into the peritoneal cavity

Intracranial hydatidosis is more common in children than in adults. The most severe complication is anaphylactic response after direct rupture into the subarachnoid spaces. We report a case of brain hydatid cyst that was accidentally drained into the peritoneal cavity and was not complicated by an anaphylactic response or dissemination.

Radiological characteristics of pulmonary hydatid disease in children: less common radiological appearances

OBJECTIVE

To evaluate the chest roentgenogram and CT characteristics of pulmonary hydatid disease (PHD).

MATERIAL AND METHODS

Forty-seven (27 male and 20 female, aged between 3 and 11 years) consecutive pediatric patients with surgically proven pulmonary hydatid cysts were enrolled for the study. Posteroanterior and lateral chest roentgenograms, CT of the chest, and laboratory findings (latex agglutination, Casoni skin test, and eosinophil count) were obtained from all of the patients. The radiological features (localization, internal architecture, number, diameter) were determined.

RESULTS

On CT examination, a total of 79 cysts were determined. On chest roentgenogram, 57 of 79 cysts were detected in all patients. Single cysts were seen in 33 patients, while multiple cysts were seen in 14. Median CT density of the cysts was 21 Hounsfield units (HU) (0-80). There were six giant cysts (>10 cm of cyst diameter). The crescent sign, water lily sign, and air-fluid level were seen in two, five and eight of the cysts, respectively. Apart from the classically described features of pulmonary hydatid cysts of the lung, a crescent-shaped rim of air at the lower end of the cyst (inverse crescent sign) was detected in three cysts. All of the liquid content of the cyst was expelled to the bronchial system (dry cyst sign) was observed in seven cysts. There were two infected cysts. Heavily calcified curvilinear cyst wall was present in one cyst. Pericystic reaction in the lung tissue was observed in five patients. Other features included pleural effusion (n=2), mediastinal shift (n=6) and atelectasis (n=7).

CONCLUSIONS

Chest roentgenogram is helpful for diagnosis of intact cysts but, it is impossible to define entire morphology of the complicated cysts. CT imaging recognize certain details of the lesions and discover others that are not visible by conventional radiography. In conclusion, CT examination should be done to elucidate cystic nature of the lung mass and for accurate localization in the preoperative period. In addition, inverse crescent sign should be recognized as feature of pulmonary hydatid cysts on CT.

Hydatid lung disease (echinococcosis/hydatidosis)

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.

Cisto hidático pulmonar gigante: relato de um caso

Os autores relatam o caso de um paciente do sexo masculino, com 55 anos de idade, branco, com diagnóstico radiológico e histopatológico pós-cirúrgico de cisto hidático pulmonar gigante. A epidemiologia, fisiopatologia e características radiológicas desta doença são discutidas.

Giant hydatid lung cysts

OBJECTIVE

In this clinical retrospective study, we aimed to evaluate giant hydatid lung cyst cases as a different clinical entity that recorded in last 10 years in our clinic.

METHODS

Between February 1990 and May 2000, a total of 305 hydatid lung cyst cases from patients that had been operated were reviewed, and 67 (21.9%) cysts with more than 10 cm in diameters of them were regarded as a giant hydatid lung cyst. Further investigations were made with respect to different factors.

RESULTS

Thirty-six (54%) cases were male and 31 (46%) were female. The ages ranged between 5 and 54 (mean 21.6) years. The most common symptoms recorded were; cough (68%), thoracic pain (55%) and dyspnea (52%). Cyst sizes were ranged between 10 and 22 cm (mean 13.4) in diameters. Forty-two (62%) of them were in the right, 22 (33%) were in the left hemithorax, and three (5%) were located bilaterally. Cystotomy or cystectomy and capitonnage was the most frequent applied operation procedure (71%). Resection was performed in nine (13%) cases. Thirteen (19%) cases had air leakage more than 10 days in which five (7%) of them empyema occurred postoperatively. One case died due to respiratory failure in fourth postoperative day. The postoperative hospital stay ranged between 6 and 43 (mean 10.5) days. No recurrence was recorded in 1-5 years of a follow-up period.

CONCLUSIONS

Giant hydatid lung cysts must be regarded as a different clinical entity because of their early occurrence, having more serious symptoms, with frequent operative complications, and they need prolonged care with higher cost effects.

Pulmonary echinococcosis (hydatidosis) in children: results of surgical treatment

From 1986-1996, 33 children with 49 pulmonary hydatid cysts underwent surgical treatment in Vienna and Istanbul. Cysts were unilateral in 28 and bilateral in 5 cases; unruptured cysts (URC) were diagnosed in 19 patients, and 14 children presented with ruptured cysts (RC). Ten patients had cysts in other organs (liver, spleen, central nervous system) in addition to pulmonary cysts. Diagnosis was primarily based on chest X-ray and computed tomography scan. In Austrian children, a new combination of serological tests was used successfully (71% positive). The standard surgical procedure was cystotomy followed by capitonnage. The main postoperative complications were fever and wound infection. There were two recurrences after a mean follow-up of 4.8 years, and one patient died because of multiple organ involvement. We conclude that the therapy of choice in pediatric pulmonary hydatidosis is complete surgical elimination of the cyst by cystotomy and capitonnage, whereas more extended resections should be avoided. Ideally, benzimidazole treatment should be combined with surgery. New serological tests can improve diagnostic accuracy.

Giant hydatid cysts of the lung

BACKGROUND

Hydatid disease is a parasitic infection caused by Echinococcus granulosus, characterized by cystic lesions in the liver, lungs, and, rarely, in other parts of the body. The large cysts in the lung are a special clinical entity called giant hydatid cysts. Characteristics on presentation, operative techniques, and postoperative morbidity and mortality rates in 47 patients with 50 giant pulmonary hydatid cysts 10 cm in diameter or larger were reported in this study.

METHODS

Cystotomy plus the obliteration of the residual cavity by imbricating sutures from within (capitonnage) was the most frequently used operative technique (n = 31), followed by pericystectomy plus capitonnage (n = 6), closure of bronchial openings plus pericystectomy (n = 6), and lobectomy (n = 3).

RESULTS

The mean age of patients with giant hydatid cyst of the lung was lower than the age of those with usual-sized cysts (p = 0.04). Five patients had prolonged air leaks (more than 10 days), three had empyema, and one had pneumonia in the opposite lung after the operation. One patient died of cardiorespiratory collapse during the operation. There was one recurrence during follow-up.

CONCLUSIONS

The increase in the diameter of the cyst in younger ages was correlated with higher lung tissue elasticity and the delay in diagnosis because of delayed symptoms in these patients. Although postoperative complications occurred in 19.1% of patients, all were managed by conservative measures, and there were no indications that the affected lung should have been treated with resection instead of a parenchyma-saving operation.