Common bile duct obstruction caused by the hydatid daughter cysts

Echinococcosis is a human parasitary disease. In 2002, 29 new cases of liver echinococcosis were recorded in Croatia. Liver is the most common site of hydatid cysts. Nine patients with echinoccocal liver disease were operated in our department in 2002. Here we present a case where a patient with verified hydatid cyst in the left liver lobe developed high fever, jaundice, nausea, vomiting and pain in the upper abdomen. The symptoms were initially ascribed to the acute cholangitis. After unsuccessful antibiotic treatment, computerized tomography and endoscopic retrograde cholangiopancreatography (ERCP) were performed, demonstrating daughter cysts in the common bile duct. During ERCP, papilotomy was made and daughter cysts were extracted. Hydatid cyst was surgically removed, and a communication between the cyst and left hepatic duct was noted during surgery. Pericystectomy, choledochotomy, removal of remaining daughter cysts from the common bile duct, and sutures of left hepatic duct were performed. The patient recovered fully after the surgery. One of the possible complications of the liver hydatid cysts is the communication between cyst and the biliary tree. Such communications are usually asymptomatic, but symptoms can also mimic acute cholangitis and jaundice, which may lead to the misdiagnosis of the patient's condition.     

Foregut Cysts

Foregut cysts frequently cause symptoms in the first three decades of life. The symptoms consist of dyspnea, wheezing, cough and sputum, dysphagia, stridor, and those associated with right heart strain. Symptoms and the radiological appearance of the uncomplicated cyst mimic mediastinal tumour and mediastinal obstruction. The symptoms and radiological appearance of the ruptured infected cyst simulate those of lung abscess, diaphragmatic hernia, ruptured hydatid cyst, cavitated peripheral carcinoma and pulmonary tuberculosis. In this series the differentiation from other cysts was made thus: with intralobar sequestration, a systemic arterial blood supply was demonstrated; with hydatid cyst, there was a positive intradermal skin test and (radiologically) following rupture, the appearance of a pericystic pneumatocele followed by the water-lily sign was diagnostic; with emphysematous cysts, the signs of associated bronchitis were present; in the presence of pseudocysts, there was a previous history of lung abscess, staphylococcal infection or tuberculosis. Cysts should be removed when first diagnosed.     

Free amino acid concentration in hydatid cyst fluids from fertile and infertile human and animal Echinococcus granulosus.

The aim of this study was to search and compare free amino acid composition of fertile and infertile cyst fluids obtained from humans and animals infected naturally with Echinococcus granulosus, by using automated analysis based on cation-exchange chromatography with post-column ninhydrin derivatization system. 11 free amino acids from fertile (sheep origin), nine from infertile (cattle origin), 13 from infertile (human origin) hydatid cyst fluids and 19 amino acids from sera of patients with hydatid infection were detected. The levels of glycine, alanine, valine and lyrosine in fertile and infertile hydatid cysts fluids were significantly higher than in sera from patients with hydatid cysts. Glycine level in the fertile hydatid cyst fluids (sheep origin) was significantly higher than those of infertile cysts fluids (cattle and human origin) and sera with hydatid patients. Glycine level in fertile hydatid cyst fluids was about two times more concentrated in infertile cattle cyst fluids, 10 times more concentrated in infertile human hydatid cyst fluids and 13 times more concentrated in sera with hydatid patients. On the other hand, alanine and valine concentration in the fertile and infertile cyst fluids were at similar level with the exception that valine level in fertile cyst fluids was 12 times more concentrated in infertile human cyst fluids. The levels of tyrosine, citrulline, leucine, isoleucine and lysine amino acids in fertile and infertile hydatid cyst fluids were similar. Our findings with respect to fertile and infertile cysts fluids showed that free amino acids concentrations in cyst fluids were significantly, higher in sera from patients with hydatid cyst. Total amount of free amino acids content in fertile and infertile cyst fluids was three to eight times higher from that of human sera with hydatid patients.     

Giant hydatid cyst of the liver with a retroperitoneal growth: a case report

ABSTRACT: INTRODUCTION: Hydatid disease is a helminthic anthropozoonosis with worldwide distribution due to the close associations among sheep, dogs, and humans. It can occur almost anywhere in the body with a variety of imaging features, which may change according to the growth stage, associated complications, and affected tissues. A definitive diagnosis requires a combination of imaging, serologic and immunologic studies. Ultrasonography, computed tomography and magnetic resonance imaging are highly accurate in detecting a hepatic hydatid cyst. However, hepatic hydatid cysts in an unusual location and/or of an unusual dimension, with atypical imaging findings, may complicate the differential diagnosis. Surgical treatment remains the best treatment. CASE PRESENTATION: We describe an unusual case of a giant hydatid cyst, with exophytic growth from the right lobe of the liver of a 55-year-old Egyptian man. The cyst was strongly adhered to his ipsilateral kidney, which was displaced in a downwards and anterior direction, close to his abdominal wall, simulating a retroperitoneal origin. This atypical growth raised doubts about the most appropriate surgical approach. Magnetic resonance imaging easily clarified the origin of the cyst as our patient's liver, allowing accurate surgical planning. CONCLUSION: Rarely, hydatid cysts can reach an extremely large size without any additional symptoms. Giant cysts need radical therapy because they might lead to perforation and anaphylaxis in some patients. Magnetic resonance imaging is very useful in the study of hydatid disease because of its capacity to allow a large field of view, multiplanar acquisition, and high contrast resolution. In some unusual hepatic presentations, magnetic resonance imaging can be used to determine the correct anatomical relationships.     

Apoptosis as a possible mechanism of infertility in Echinococcus granulosus hydatid cysts

Echinococcus granulosus is a parasitic cestode causing hydatidosis in intermediate hosts (human and herbivorous). Most symptoms of the disease occur by the pressure exerted on viscera by cysts that are formed upon ingestion of the parasite eggs excreted by definitive hosts (canines). Protoscoleces, the developmental form of the parasite infective to definitive hosts, are formed in the germinal nucleated layer of fertile hydatid cysts. For unknown reasons, some cysts are unable to produce protoscoleces (infertile hydatid cysts). In this study, analysis of DNA fragmentation using TUNEL and agarose gel electrophoresis showed higher levels of apoptosis in infertile cysts as compared to fertile cysts. Additionally, caspase 3 was detected both in fertile and infertile cysts; the activity of this enzyme was found to be higher in infertile cysts. We conclude that apoptosis may be involved in hydatid cyst infertility. This is the first report on the presence of programmed cell death in E. granulosus.     

Comparative cytotoxicity of secondary hydatid cysts, protoscoleces, and in vitro developed microcysts of Echinococcus granulosus.

Infection with the metacestode of Echinococcus granulosus is characterized by a concomitant immunity. Survival of established and developing hydatid cysts in the intermediate host implies a mechanism to modulate its immunological reactions. In order to investigate this mechanism, secondary hydatid cysts were isolated from intraperitoneally infected laboratory white mice (strain NMRI) 12 months p.i. A number of hydatid cysts were freed from the surrounding host adventitial tissue. Monolayer cultures of non-stimulated peritoneal macrophages of NMRI mice were prepared and incubated in the presence of the hydatid cysts. By means of a trypan blue exclusion test and by measuring the incorporation of tritium labelled uridine, it was found that the presence of hydatid cysts reduced the viability of the macrophages in vitro. Toxic substances are probably secreted since the medium of cultured hydatid cysts also displayed cytotoxic activity. Hydatid cysts with adventitia, as well as culture medium of those cysts, were less toxic. When toxins, partially purified from hydatid cyst fluid, were previously incubated on a collagen coated surface, a reduced level of toxicity was found, suggesting that collagen of the host adventitia may play a role in controlling the liberation of toxins by the hydatid cyst. Virtually no toxicity was exerted by protoscoleces or by the medium of cultured protoscoleces, in contrast to in vitro vesiculated protoscoleces (so called microcysts). The results reveal a novel feature of hydatid cysts that may play a role in the survival of the parasite in the immunized host.     

Multiple unusual locations of hydatid cysts including bladder, psoas muscle and liver

Our case concerns 66-year-old female with a multiple unusual locations of hydatid cysts including bladder, psoas muscle and liver. Coexistence of hydatid cysts in these localizations has not been previously reported. The diagnosis of vesical hydatid cyst was facilitated by the coexistence of other echinococcosis locations. Treatment consists of the excision of the cysts in the same session without any postoperative anthelmintic drugs. In a two-year follow-up no recurrence has occurred.     

Comparative electrophoretic study of phosphoglucose isomerase,phosphoglucose mutase and tetrazolium oxidase in some hydatid cysts of Echinococcus granulosus collected from different mammal hosts

Hydatid cyst scolexes of lung and liver from sheep and water buffalo were electrophoreticaily examined for phosphoglucose isomerase (PGI), phosphoglucose mutase (PGM) and tetrazolium oxidase (Te) activity. One each of phosphoglucose isomerase, phosphoglucose mutase and tetrazolium oxidase activities were found in all of the hydatid cysts studied. PGI and PM in ail hydatid cysts studied appeared te be controlled by two codominant alleles. PGI and PGM proved to be a good taxonomic criterion to differentiate the hydatid cysts of the water buffalo from those from sheep. On the other hand, TO failed to differentiate between the sheep and water buffalo hydatid cysts. The hydatid cysts that parasitise the sheep's organs can be considered as arising from a different strain from the cysts that parasitise the water buffalo organs, while lung and liver hydatid cysts of the sheep appeared to be a similar strain.     

Medical treatment of pulmonary hydatid disease: for which child?

There have been many encouraging studies on medical treatment of pulmonary hydatid disease due to Echinococcus granulosus infection. Our aims were to demonstrate the safety and efficacy of medical treatment in pulmonary hydatid disease and to describe a pediatric population who would benefit from medical treatment, especially in respect to the diameter of the hydatid cyst. All patients were treated with mebendazole or albendazole. Treatment outcome was defined as cure, improvement or failure. Among 82 patients, 34.1% were cured, 34.1% improved and 31.8% failed. When 102 cysts were individually evaluated, 36.31% were cured, 32.4% improved and 31.3% failed. The cure and the failure rates were statistically insignificant in cysts treated with mebendazole and albendazole; however statistically significantly more cysts were improved with albendazole. The results were statistically insignificant between continuous and cyclic albendazole treatment. The mean size of successfully treated cysts was 5.3+/-3.4 cm, but "failed" for cyst with a mean size of 7.3+/-4.3 cm. There was a positive, weak and statistically significant correlation between the cyst size and treatment results. The major complication was infection. We suggest that selected pediatric patients with uncomplicated pulmonary hydatid cysts sized less than 5 cm should have a trial of medical treatment with a very close follow up.     

Hydatid cyst in soft tissues mimicking malignant tumors. Diagnosis by fine needle aspiration cytology

OBJECTIVE: To evaluate the role of fine needle aspiration cytology in the diagnosis of soft tissue hydatid cysts. STUDY DESIGN: Five cases of soft tissue hydatid cyst were diagnosed primarily by fine needle aspiration cytology. RESULTS: In all cases, large fragments of acellular material, finely lamellated, were found. There were no complications related to fine needle aspiration, and histologic studies confirmed the diagnosis of hydatid cyst. CONCLUSION: When acellular, laminated fragments suggestive of a laminated layer are identified on smears, hydatid cyst should be considered in the differential diagnosis, even in atypical locations and in the absence of hooklets, protoscolices or both.     

Primary Renal Hydatid Cyst: Mis-Interpretation as a Renal Malignancy

Primary renal echinococcosis, a rare disease involving the kidney, accounts for 2-3% of human echinococcosis. A 64-year-old female patient from Uzbekistan presented with complaints of left flank pain. A CT scan revealed a cystic mass in the upper to midpole of the left kidney. We regarded this lesion as a renal malignancy and hand-assisted laparoscopic radical nephrectomy was performed to remove the renal mass. The mass consisted of a large unilocular cyst and multiple smaller cysts without any grossly visible renal tissue. The final pathologic diagnosis was a renal hydatid cyst. For patients from endemic areas, hydatid cyst should be included in the differential diagnosis. Here, we present a case of renal hydatid cyst in a female patient who relocated from Uzbekistan to Korea.     

Echinococcus granulosus (Cestoda: Taeniidae) infections in moose (Alces alces) from southwestern Quebec

Investigation of the distribution of larval Echinococcus granulosus in a moose population from southwestern Quebec revealed a distinct and stable pattern of infection with a prevalence of 44% (n = 580). Positive correlations between moose age and the intensity, mean cyst weight and biomass of the hydatid cysts suggested a process of continued parasite acquisition and cyst growth. The distribution of cyst sizes within individual moose provided circumstantial evidence of interaction between cysts, perhaps mediated through the host's immunological response.     

Clustering of hydatid infection in macropodids

The introduced parasite, Echinococcus granulosus, has been reported in numerous macropodid species in various areas of Australia, but no extensive studies investigating the prevalence and risk factors for infection in wild macropodids have been reported. In this study, 2998 macropodid carcasses were examined following commercial culling on 21 properties in southern Queensland. Of the 71 infected animals, all had cysts in the lung tissue, while two also had cysts in the pleural cavity and one animal had a liver cyst. The number of cysts in infected animals ranged from 1 to 17, with the majority of animals (n=64) having one to three cysts. Estimated total cyst volume varied from 0.2 to 1075 cm3. Some animals had a total lung cyst volume likely to have impacted significantly upon respiratory function and cyst degeneration was only seen in approximately one-third of infected animals. Multilevel models were used to investigate putative risk factors at both kangaroo and property levels. At the kangaroo level, females were twice as likely to be infected as males. After adjusting for sex, no property-level risk factors were significantly associated with the presence of hydatid infection. Prevalence varied substantially between properties (range 0-12%) and this high degree of clustering of infection was reflected in a high intra-class correlation co-efficient in the final model (0.333). These results have important implications for both public health and conservation strategies, and suggest that there are important unidentified risk factors for hydatid infection associated with properties. They also demonstrate that spatial clustering should be considered when analysing hydatid infection data in macropodids, particularly when assessing area-level risk factors.     

Echinococcus granulosus: DNA extraction from germinal layers allows strain determination in fertile and nonfertile hydatid cysts

A method for the isolation of Echinococcus granulosus DNA from germinal layers of hydatid cysts is described. The method includes a hexadecyltrimethylammonium bromide/chloroform extraction and an adsorption to diatomaceous earth suspension. DNA suitable for polymerase chain reaction was obtained and used for parasite strain determination by mitochondrial cytochrome c oxidase I gene sequencing. Fertile and nonfertile cyst isolates from sheep, cattle, pigs, and humans were characterized. Hitherto, no direct parasite strain characterization has been made on nonfertile hydatid cysts, whereas here we report that nonfertile hydatid cysts were produced by sheep strain (G1 genotype) in sheep, cattle, and humans and by pig strain (G7 genotype) in pigs.     

DNA damage, RAD9 and fertility/infertility of Echinococcus granulosus hydatid cysts

Hydatidosis, caused by the larval stage of the platyhelminth parasite Echinococcus granulosus, affects human and animal health. Hydatid fertile cysts are formed in intermediate hosts (human and herbivores) producing protoscoleces, the infective form to canines, at their germinal layers. Infertile cysts are also formed, but they are unable to produce protoscoleces. The molecular mechanisms involved in hydatid cysts fertility/infertility are unknown. Nevertheless, previous work from our laboratory has suggested that apoptosis is involved in hydatid cyst infertility and death. On the other hand, fertile hydatid cysts can resist oxidative damage due to reactive oxygen and nitrogen species. On these foundations, we have postulated that when oxidative damage of DNA in the germinal layers exceeds the capability of DNA repair mechanisms, apoptosis is triggered and hydatid cysts infertility occurs. We describe a much higher percentage of nuclei with oxidative DNA damage in dead protoscoleces and in the germinal layer of infertile cysts than in fertile cysts, suggesting that DNA repair mechanisms are active in fertile cysts. rad9, a conserved gene, plays a key role in cell cycle checkpoint modulation and DNA repair. We found that RAD9 of E. granulosus (EgRAD9) is expressed at the mRNA and protein levels. As it was found in other eukaryotes, EgRAD9 is hyperphosphorylated in response to DNA damage. Our results suggest that molecules involved in DNA repair in the germinal layer of fertile hydatid cysts and in protoscoleces, such as EgRAD9, may allow preserving the fertility of hydatid cysts in the presence of ROS and RNS.     

Fine structure of the germinal membrane of Echinococcus granulosus cysts.

The ultrastructure of the hydatid cyst germinal membrane was studied. It was divided into 3 regions, the tegument, the tegumental cell region, and the innermost area bordering the cyst cavity. The morphology of tegumental, muscular, flame, duct, and glycogen-containing cells and cells containing lysosomal-like bodies is described. The significance of these findings is discussed in terms of the possible function of these structures and present knowledge on the penetration of macromolecules into hydatid cysts.     

Treatment of hepatic hydatid cysts by percutaneous aspiration and hypertonic saline injection: results of a cooperative work

Percutaneous puncture-aspiration-injection-reaspiration (PAIR) of hydatid liver cysts, was performed in 38 patients 14-80 years old, with a total of 60 liver hydatid cysts. After aspiration under computed tomography guidance, hypertonic saline was injected into the cystic cavities of patients as a scolecidal agent. No major complications were associated with the procedures. In the follow-up period of 18 months, control CT scans of 35 cysts revealed a gradual decrease in cyst size with a mean volume reduction of 66%. Complications included two cases of urticaria, one case of anaphylaxis and one subcapsular hematoma. No mortality occurred. It is concluded that percutaneous aspiration and hypertonic saline injection for liver hydatid cysts appears to be an effective form of treatment and may eventually prove to be an alternative to surgical intervention.     

Intraabdominal hydatid cyst: a case report

BACKGROUND: Hydatid disease is caused by Echinococcus granulosus, endemic in cattle and sheep-raising regions of the world such as Central Europe, South America, Australia, New Zealand and South Africa. Although hydatid disease is more common in liver and lung, it also affects brain, kidney, spleen and muscle. We present a case of intraabdominal hydatid cyst, diagnosed by fine needle aspiration cytology, producing an indentation of the liver, which is uncommon. CASE: A male patient presented with right side abdominal pain. On ultrasonography an intraabdominal solid mass (right hypochondrial) was revealed, and subsequently FNA was done. Smears were diagnostic of hydatid cyst. CONCLUSION: FNAC is a sensitive and rapid technique in diagnosis of hydatid cysts. The present case is unusual, owing to its presentation as a solid abdominal mass seeding over the liver and mimicking malignancy radiologically.     

Observations on the suitability and importance of the domestic intermediate hosts of Echinococcus granulosus in Uttah Pradesh, India

The present study investigated the suitability and importance of buffaloes, camels, sheep, goats and pigs in maintaining the life-cycle of Echinococcus granulosus in Aligarh, India. A total of 565 (36%) of 1556 buffaloes, 20 (2%) of 1208 goats, 5 (1%) of 559 pigs, 6 (6%) of 109 sheep and two of three camels were found to harbour hydatid cysts. The frequency distribution of the hydatid cysts in each intermediate host species was over-dispersed and in buffaloes cyst fertility increased with increasing cyst size. Of 2171, 95 and four buffalo, goat, and camel cysts examined 327 (15%), two (2%) and three cysts respectively were fertile. No pig or sheep cysts were found to contain protoscoleces. The unfenced buffalo abattoir and the large number of dogs allowed access to the abattoir coupled to the number of buffalo slaughtered in comparison to the other potential hosts, indicates that the buffalo is the most significant host for maintaining the life-cycle of the parasite in this area of India. Applicable control measures for the region are suggested.     

Effect of mouse strain variations and cortisone treatment on the establishment and growth of primary Echinococcus multilocularis hydatid cysts

The main purpose of this study was to determine the effects of cortisone on the number and size of primary Echinococcus multilocularis cysts developing in a moderately resistant strain of mice, i.e., C3H/HeJ. Computerized image analysis was used to measure the surface area occupied by hydatid cysts 10 wk after inoculation of the mice with E. multilocularis eggs. Our second objective was to compare the infectivity of primary E. multilocularis hydatid cysts in C57BL/6J-Ay/a (lethal yellow) mice with that in C57BL/6J-a/a (non-agouti black) mice. The data obtained show no difference between the C3H/HeJ and C57BL/6J-a/a strains of mice; yet, the image analysis method was able to detect a slight increase in the total cyst size within the Ay/a mutant of the C57BL/6J strain. Treatment of C3H/HeJ mice with cortisone drastically increased both the number of cysts and the average size of each cyst when the treatment occurred early in the infection.