Brood Capsules Research Articles

Aspectos morfológicos e impactos patológicos da equinococose cística no fígado de ovelhas abatidas e relação hospedeiro-parasita

ABSTRACT Cystic echinococcosis (CE) is a parasite-borne disease caused by the larval stage of Echinococcus granulosus belonging to family Taeniidae, is an endemic disease, distributed worldwide as a neglected parasite with socioeconomic repercussions. It causes severe alterations in liver of infected host, and it could be fatal if untreated. The main objective of the present study is to measure and evaluate the condition of hydatidosis in slaughtered sheep in Al Baha region, Saudi Arabia. A total of 601 slaughtered sheep in Al Baha abattoirs were examined for hydatidosis during the year 2020. Various organs were examined for the presence of parasite cysts, and the cyst contents were examined by light microscopy. Also, liver sections infected with cysts were examined for pathological alterations and host-parasite interactions. Forty-two animals were infected (6.09%) with the highest prevalence during summer. During gross examination, it was observed that the sheep liver is the most affected organ by the disease. The liver contained multiple cysts with varying sizes, filled with clear to slightly turbid fluid containing protoscoleces. Detailed sections of the infected liver revealed significant fibrosis around the central vein, portal vein congestion, infiltration of inflammatory cells, and necrosis. Sections through hydatid cysts showed the presence of three surrounding layers with a laminar membrane bordering the cyst lined by a germinal epithelium surrounding several brood capsules with many protoscolesces inside supported by a set of rostellar hooklets. Considerable efforts should be spent to control the transmission of parasitic cysts and inhibit the incorrect disposal of infected meat from slaughterhouses. Also, more focus should be done on epidemiological and control programs of these parasites.

Transforming growth factor-β signalling regulates protoscolex formation in the Echinococcus multilocularis metacestode.

The lethal zoonosis alveolar echinococcosis (AE) is caused by tumor-like, infiltrative growth of the metacestode larval stage of the tapeworm Echinococcus multilocularis. We previously showed that the metacestode is composed of posteriorized tissue and that the production of the subsequent larval stage, the protoscolex, depends on re-establishment of anterior identities within the metacestode germinative layer. It is, however, unclear so far how protoscolex differentiation in Echinococcus is regulated. We herein characterized the full complement of E. multilocularis TGFβ/BMP receptors, which is composed of one type II and three type I receptor serine/threonine kinases. Functional analyzes showed that all Echinococcus TGFβ/BMP receptors are enzymatically active and respond to host derived TGFβ/BMP ligands for activating downstream Smad transcription factors. In situ hybridization experiments demonstrated that the Echinococcus TGFβ/BMP receptors are mainly expressed by nerve and muscle cells within the germinative layer and in developing brood capsules. Interestingly, the production of brood capsules, which later give rise to protoscoleces, was strongly suppressed in the presence of inhibitors directed against TGFβ/BMP receptors, whereas protoscolex differentiation was accelerated in response to host BMP2 and TGFβ. Apart from being responsive to host TGFβ/BMP ligands, protoscolex production also correlated with the expression of a parasite-derived TGFβ-like ligand, EmACT, which is expressed in early brood capsules and which is strongly expressed in anterior domains during protoscolex development. Taken together, these data indicate an important role of TGFβ/BMP signalling in Echinococcus anterior pole formation and protoscolex development. Since TGFβ is accumulating around metacestode lesions at later stages of the infection, the host immune response could thus serve as a signal by which the parasite senses the time point at which protoscoleces must be produced. Overall, our data shed new light on molecular mechanisms of host-parasite interaction during AE and are relevant for the development of novel treatment strategies.

Cough, bloody sputum, eosinophil elevation and lung shadow

A 47-year-old man was referred to the pulmonary clinic with a 2-year history of productive cough and 3-month history of hemoptysis. Two years ago, his chest CT scan revealed a 2 cm×2 cm well-defined nodule in the right upper lung. His cough was alleviated without treatment. Three months ago, he had a productive cough with the bloody sputum after a running to catch the bus. Physical examination was normal. Complete blood count (CBC) showed an elevated eosinophil count (42.61%). Chest CT scan showed that the enlargement of the right upper lobe nodule (3.4 cm×3.3 cm), with bilateral pathy lesions distributed in the right upper lobe and the left lower lobe. Pathological study of needle specimen biopsy showed the lamellated cyst wall of hydatid cyst, brood capsule formation and hooklet. Pulmonary hydatidosis was diagnosed. It was recommended that the patient should be treated by surgery combined with albendazole. His symptoms relieved and lung nodules were shrinking without treatment after 5 years follow-up.

Radiological, Laparoscopic, Cytology-Histology Correlation of Hepatic and Pelvic Hydatid Cyst

•Hydatid cyst results when humans get infected by ingesting the eggs of Echinococcus Granuloses. The oncospheres penetrate the intestinal wall and migrate to various organs. They develop into hydatid cyst and gradually is filled with daughter cysts.•We present a 69-year-old female, a native of Uzbekistan, who presented with vague right upper quadrant pain. Radiologically 20 cm liver cyst and multiple pelvic cysts with a stage of CE2 (Fig. A). Serology for Echinococcal antibody was positive.•After 2 months of Albendazole, she underwent Laparoscopic puncture aspiration and injection with 20% saline (PAIR) and peri-cystectomy of the pelvic cysts. After uneventful recovery and further Albendazole, she underwent a Robotic-assisted PAIR and partial peri-cystectomy of the liver cyst with the repair of the duct to cyst communication. (Fig. F, G, H, I). She did need a post-operative ERCP with Sphincterotomy and then was asymptomatic 2 weeks after. Her Serology tuned intermediate 2 months later.•Pathology:1.Cytology: Aspirate: Scattered scolices, inflammatory cells, and abundant amorphous debris consistent with hydatid cyst (Fig. B)2.Gross: Bilateral 5-cm pelvic cysts with pale yellow, soft to firm walled, multiple cavities (Fig. C)3.Microscopy - Fibrofatty outermost layer and a two-layered cyst wall including a thin germinal epithelium covered by a thick acellular outer membrane (Fig. D), Multiple parasites, some eosinophilic (Fig. E)4.Liver cyst - daughter cysts of Echinococcus and brood capsule with protoscolices (Fig. H)•Our case highlights the role of correlating various modalities in the diagnosis of hydatid disease.

Movement of Echinococcus granulosus under a light microscope

Echinococcosis, also known as hydatid cyst infection in humans and dwarf tape worm infection in dogs, is a zoonotic disease with a worldwide distribution. Echinococcosis is a significant health issue and carries commercial losses. It is caused by the metacestode stage of the dog tapeworm Echinococcus granulosus. This is a small worm, less than 1 cm long, that attaches to the intestinal villi. The life cycle of the genus Echinococcus involves two mammalian hosts. The definitive hosts are carnivorous dogs that become infected by ingestion of protoscoleces, consumed within the hydatid cyst as free brood capsules in contaminated meat, or within the tissue of the intermediate host.

Hepatic echinococcus granulosus: a clinicopathological analysis of thirteen cases

Objective: To investigate the clinicopathologic characteristics of hepatic echinococcus granulosus (HEG). Methods: Thirteen cases of HEG were collected from Linzhi People's Hospital between January 2017 to October 2020, and their clinicopathologic features, ultrasound classification, immunophenotype and histochemical data were analyzed, retrospectively and the relevant literature was reviewed. Results: Thirteen patients (5 male patients, 8 female patients) were included in this cohort, and the mean age was 40 years. The most common clinical presentation was mild abdominal distention and pain (9/13). Based on WHO-IWGE ultrasound standardized classification, these cases were classified into 5 types, including type CL (1 case), type CE1 (2 cases), type CE2 (4 cases), type CE3 (3 cases) and type CE4 (3 cases). Gross examination revealed a solitary cyst localized in the liver, varying from 2.7 to 13.5 cm in diameter, and most of them(10/13)were more than 10 cm. Histopathologically, these cysts possessed a thin inner germinal layer and outer adventitial layer, and a central cavity filled with a clear"hydatid"fluid. The germinal layer was continuous and generated brood capsules and protoscoleces. The laminated membranes were clearly demonstrated by elastic fiber and Gomori's stains. Inside the"mother"cyst, there were a varying number of"daughter"vesicles of variable sizes. The inflammatory reaction around the cyst consisted of eosinophils, mononuclear cells immediately next to the cyst layer and sometimes formed granuloma and giant cells resembling the Langhan's type giant cells. The lymphoid cells were positive for CD20 and CD3. The CD68 immunohistochemistry clearly demonstrated epithelioid cells of granuloma in two cases. Moreover, immunohistochemistry revealed plasma cells were locally positive for CD38, IgG and IgG4, but not meeting the criteria for IgG4 related lesion. Conclusions: Hepatic echinococcus granulosus is a zoonotic parasitic disease prevalent in pastoral areas such as Tibet. It is important to understand its clinical features, ultrasound characteristics and histological morphology.

Cytology-Histology Correlation of Hydatid Cyst: A Case Study and Literature Review

Abstract Casestudy: Hydatid cyst results when humans get infected by ingesting the eggs of Echinococcus Granulosus. Upon release, the six-hooked oncospheres penetrate the intestinal wall and migrate via circulation to various organs, mostly liver and lung. Here, they develop into hydatid cyst. The cyst enlarges gradually and is filled with daughter cysts and protoscolices. We report the case of a 69-year old female, native of Uzbekistan, who presented with right upper quadrant pain. Imaging showed a 20 cm liver cyst and multiple pelvic cysts with a stage of CE2 implying that they were most likely functional. Serum Echinococcal antibody was positive. After 2 months of Albendazole treatment, there was no radiological change. The patient underwent laparoscopic puncture aspiration and injection with 20% saline (PAIR) and pericystectomy of the pelvic cysts. The aspirate revealed scattered scolices, inflammatory cells and abundant amorphous debris consistent with hydatid cyst. Bilateral 5-cm pelvic cysts had pale yellow, soft to firm walled, multiple cavities. Microscopy revealed a fibrofatty outermost layer with chronic inflammation and a two-layered cyst wall including a thin germinal epithelium covered by a thick acellular outer membrane. Multiple parasites, some degenerate (dense eosinophilic) were present, confirming the cytologic diagnosis of cystic echinococcosis. Following further treatment with Albendazole, she underwent a robotic assisted PAIR and partial peri-cystectomy of the liver cyst with repair of the duct to cyst communication. The liver cyst contained daughter cysts of Echinococcus and brood capsule with protoscolices. After 2 months more of Albendazole her Elisa was intermediate. A prior study reported cytopathologic diagnosis of hydatid cyst in 17 patients evaluated for various masses. Our case highlights the role of cytology sampling in confirming the diagnosis of hydatid disease. Potentially fatal in untreated patients, this entity has to be considered in the differential diagnosis of cystic lesions.

Ultrastructure of Human Fertile Hydatid Cysts Using a Scanning Electron Microscope (SEM)

Introduction: Echinococcosis and hydatidosis caused by the metacestode of Echinococcus granulosus are among the most important zoonotic diseases in the world. This study aims to study the ultrastructure of fertile hydatid cysts that infect humans using a scanning electron microscope (SEM). Materials and Methods: Twenty samples of human fertile hydatid cysts were collected from the human liver and lung after performing surgery operations and examined with an SEM. Results: The results of the electron microscopy with different magnifications revealed that the laminated layer (LL) consists of sheets that appeared more compact and aligned. The brood capsules appeared, consisting of a net of finger-shaped structures that emerged from bulges of various sizes and shapes. Conclusion: Under a transmission electron microscope, it was found that the LL had a coherent and flexible structure, settling on a three-dimensional microscopic network of hydrophilic fibers, with high humidity. These fibers were arranged irregularly and had a diameter of about 10 nm; therefore, the fibers adjacent to the germinal layer (GL) were possibly attached to microtriches of tegument, which reached a thickness of 1 mm in the LL.

In vitro culture of Echinococcus multilocularis producing protoscoleces and mouse infection with the cultured vesicles.

BackgroundAlveolar echinococcosis (AE) is a lethal zoonosis caused by the fox-tapeworm Echinococcus multilocularis. The disease is difficult to treat and an effective therapeutic drug is urgently needed. Reliable models are essential for drug development. In this study, we developed both in vitro and in vivo models of larval E. multilocularis.ResultsThe protoscoleces (PSC) of E. multilocularis from jirds were successfully cultured in a modified RPMI1640 based medium containing 25 % (v/v) fetal bovine serum (FBS). After 100 days of culture, PSC developed to larval vesicles (small unilocular cysts) and the fast growing vesicles produced PSC in brood capsules. In addition, mice were intraperitoneally injected with 30 cultured small vesicles and 100 % of the mice had resulting metacestode masses.ConclusionsLarval protoscoleces and vesicles of E. multilocularis grow healthily in vitro in the RPMI1640 based medium containing 25 % FBS. Echinococcus multilocularis in vitro and in vivo models provide a valuable platform for investigating the biology of the parasite and screening effective therapeutic drugs against AE.

An Echinococcus multilocularis Antigen B3 Proteoform That Shows Specific Antibody Responses to Active-Stage Alveolar Echinococcosis.

Alveolar echinococcosis (AE), caused by the Echinococcus multilocularis metacestode, represents one of the most frequently fatal zoonoses. Early diagnosis significantly reduces morbidity and mortality associated with AE. Diagnosis of AE largely depends on a combination of imaging and serological tests due to its minimal clinical manifestations. Several antigens derived from the whole worm and protoscolex have been targeted for AE serodiagnosis, while the antigenic properties of E. multilocularis hydatid fluid (EmHF) are unclear. We observed two AE-specific 6- and 8-kDa antigen proteoforms through an immunoproteome array of the EmHF. We identified these proteins as representing an E. multilocularis antigen B3 (EmAgB3) isoform, and the proteins were shown to be encoded by the same gene. We cloned the gene and expressed the recombinant EmAgB3 protein (rEmAgB3) in Escherichia coli. rEmAgB3 exhibited sensitivity of 90.9% (80/88 cases) and specificity of 98.5% (597/606 samples) by immunoblotting. The positive and negative predictive values were 89.9% and 98.6%, respectively. The protein did not show antibody responses to 33 AE sera collected during posttreatment follow-up monitoring. Mouse sera experimentally infected with AE protoscoleces began to demonstrate specific antibody responses to native and recombinant EmAgB3 6 months after infection. At that stage, fully mature metacestode vesicles that harbored the brood capsule, primary cell, and protoscolex were observed within an AE mass(es). The response declined along with worm degeneration. Our results demonstrate that the immune responses to this EmAgB3 isoform were highly correlated with worm viability accompanied with AE progression. rEmAgB3 is a promising biomarker for serological assessment of AE patients.

Pulmonary hydatidosis in a tertiary care hospital.

Background:Hydatid disease is caused by the larval stage of Echinococcus. Liver is the most commonly involved organ followed by the lungs. Pulmonary hydatidosis can be primary or secondary. The disease may be asymptomatic for several years. Cause of concern is the fatal anaphylaxis, which may be life threatening.Materials and Methods:The present retrospective study is over a period of ten years (2003-2012). The demographic data including the clinical features, radiological findings, other organ involvement, surgical and medical management done and histopathological findings were compiled from the records.Results:During the study period a total of eight cases, five male and three female, with age ranging from eight to 43 years were diagnosed as pulmonary hydatid disease. Five patients had presented with complicated cysts. Six patients had solitary cysts involving the lung while bilateral lung involvement was seen in two cases. One patient had multiple pulmonary cysts. Three patients had associated cysts in liver and two in spleen. Surgical lobectomy was done in four cases. Histopathology showed acellular laminated ectocysts in all the cases, whereas endocyst with brood capsules was seen in five cases.Conclusions:Pulmonary hydatidosis is not uncommon. Anaphylaxis, although rarely seen, may be a disastrous event. High index of clinical suspicion and mass awareness for interruption of transmission of parasite can lead to proper treatment and possible eradication.

Studies on the Protoscoleces and Hooks of Echinococcus Granulosus from Libya by Scanning Electron Microscope

Introduction: Protoscolex and hook morphology had been used to identify different strains of Echinococcus granulosus. Method: In the present study, hydatid sand was isolated from infected organs such as liver, lung and spleen from slaughtered animals in several abattoirs in the selected study areas in Libya. Scanning Electron Microscope (SEM) was used to describe the outer surface of the Protoscoleces and the hooks. Result: SEM pictures showed different morphological characters of the outer surface of the different parts of the same protoscolex. Also, the buds on the outer surface of brood capsule, and showed some differences between the large and small hooks. These findings appeared the that there was a correlation with significant statistical difference between the measurements of large as well as small hooks from the same organs of each host as well as between different hosts. Conclusion: Finally, it was difficult to determine whether these cases are not real distortions in the morphology of E. granulosus. They possibly could be caused by mutation or related to a special strain of E.granulosus. Thus, the findings of the present study would suggest that there is a need to consider relationships between the different characters of hooks with different strains of E.granulosus.

A rare case of spleenic hydatidosis in a buffalo: patho-morphological study.

Hydatidosis, a zoonotic disease caused by the metacestode of Echinococcus granulosus is considered an economically important disease due to the condemnation of affected visceral organs of domestic animals. The lungs and liver are the most commonly affected organs and is less frequently observed in spleen particularly in buffaloes compared to cattle. Out of 980 slaughtered buffaloes screened for hydatidosis a case of spleenic hydatidosis was noticed. A single cyst projecting from the surface of the spleen was observed. On incision clear watery fluid along with granular structures (protoscolices) escaped out. The inner surface of cyst contained thin, white, translucent membrane studded with cluster of brood capsules. Microscopic examination revealed germinal layer with protoscolices along with eosinophilic laminated layer. There was fibrous connective tissue proliferation around the laminated layer and a mild depletion of the lymphoid cells in the surrounding white follicles.

Cerebral Cystic Echinococcosis in the Light of Our Experience

Cerebral cystic echinococcosis (CCE) is rare and constitutes 1-2% of all cystic echinococcosis. The cysts are usually solitary and most frequently located in the supratentorial region. CCE is classified as primary and secondary. The primary cysts developed from the embryos which escaped from the filter systems are more frequent and usually solitary and fertile. The secondary cysts result from spontaneous, traumatic or surgical rupture of the primary CCE by embolization of scolices. They are usually multiple and infertile and do not have brood capsule or scolices. Symptoms usually develop slowly and are usually due to increased intracranial pressure and depend on the location of the cyst. Diagnosis is made by evaluation of both clinical and laboratory findings. Computed tomography and magnetic resonance imaging is successful in the diagnosis. The cysts are observed as spherical, well defined, with thin regular margins by these methods. The most appropriate treatment method is total surgical removal of the cyst without rupture by using Dowling's method. However, when it is not possible to remove without rupture, the cyst should be removed totally after puncture and aspiration of contents of the cyst. After removal of large cysts, complications such as porencephalic cysts and subdural hemorrhage can occur postoperatively.

A rare case of primary multiple hydatid cysts of the brain in a 10-year-old child

Echinococcus is a cestode. The most common Echinococcus species causing human infection are E. granulosus and E. multilocularis [1]. The commonest sites for cysts are the liver (59%–75%), followed in frequency by lung (27%), kidney (3%), bone (1%–4%) and brain (1%–2%). Other sites such as the heart, spleen, pancreas and muscles are very rarely affected [2]. Multi-organ involvement without liver cysts is reported [3]. Brain cysts caused by E. granulosus are rare; they occur during childhood in endemic areas [4]. Cerebral hydatid cysts are usually supratentorial and tend to occur in the middle cerebral artery distribution [5]. The cyst’s predilection for white matter is undisputed, but the exact reason for this is unknown; some believe it is because of the arterial distribution [6]. Cerebral hydatid cysts are solitary. Multiple hydatid cysts in brain parenchyma are very rare and result from spontaneous, traumatic or postsurgical rupture of cysts in the brain or elsewhere; with embolization of hydatid to brain, multiple cysts may arise in the brain itself [5–8]. Cerebral hydatid cysts are classified as primary or secondary. Primary intracranial hydatid cyst results from direct infestation of the brain by the larva without involvement of other organs such as liver and lungs. Primary cysts are fertile, containing brood capsules and scolices, and their rupture may result in recurrent intracranial hydatid cyst. Primary cysts are usually solitary. Primary multiple cerebral hydatid cysts are quite unusual, resulting from multiple larvae infecting the brain after bypassing the liver and lungs [8,9]. Secondary cysts are generally multiple and result from the rupture of hydatid cysts in the brain or in other organs of body. These cysts lack germinal membranes and are infertile, with negligible risk of recurrence after rupture [6,7,10]. Here we report a rare case of primary multiple hydatid cysts of the brain in a 10-year-old child, with a total of 73 cysts removed from his cerebrum and 5-year follow-up. Written informed consent was obtained from the patient’s parents for publication of this case report and any accompanying images. A copy of the written consent is available for review by the Eastern Mediterranean Health Journal’s Editor-In-Chief.

Echinococcus multilocularis: Single hepatic lesion experimentally established without metastasis in rats

We herein describe the establishment of single hepatic lesions of Echinococcus multilocularis in rats. A 3mm incision was made on the liver with a surgical knife, and one small round vesicle of E. multilocularis (between 1×1mm and <2×2mm in diameter) was transplanted into the incision and covered with absorbable hemostat gauze. The presence and growth of the transplanted vesicle was monitored for 12weeks using magnetic resonance imaging (MRI). Hepatic lesions, the metacestode of this parasite were confirmed in 12 of 17 infected rats (70.6%) by MRI and macroscopic examinations. The average size of the metacestodes with brood capsules at 12weeks after the experimental transplantation of a single vesicle was 6.1±2.5mm×4.4±1.5mm. The smallest size of the metacestodes detected by MRI was approximately 3×3mm. This new approach of establishing single hepatic metacestodes of E. multilocularis in experimental animals is expected to be useful for analyzing the immune-pathological mechanisms of hepatic AE.

Anatomy and development of the larval nervous system in Echinococcus multilocularis

BackgroundThe metacestode larva of Echinococcus multilocularis (Cestoda: Taeniidae) develops in the liver of intermediate hosts (typically rodents, or accidentally in humans) as a labyrinth of interconnected cysts that infiltrate the host tissue, causing the disease alveolar echinococcosis. Within the cysts, protoscoleces (the infective stage for the definitive canid host) arise by asexual multiplication. These consist of a scolex similar to that of the adult, invaginated within a small posterior body. Despite the importance of alveolar echinococcosis for human health, relatively little is known about the basic biology, anatomy and development of E. multilocularis larvae, particularly with regard to their nervous system.ResultsWe describe the existence of a subtegumental nerve net in the metacestode cysts, which is immunoreactive for acetylated tubulin-α and contains small populations of nerve cells that are labeled by antibodies raised against several invertebrate neuropeptides. However, no evidence was found for the existence of cholinergic or serotoninergic elements in the cyst wall. Muscle fibers occur without any specific arrangement in the subtegumental layer, and accumulate during the invaginations of the cyst wall that form brood capsules, where protoscoleces develop. The nervous system of the protoscolex develops independently of that of the metacestode cyst, with an antero-posterior developmental gradient. The combination of antibodies against several nervous system markers resulted in a detailed description of the protoscolex nervous system, which is remarkably complex and already similar to that of the adult worm.ConclusionsWe provide evidence for the first time of the existence of a nervous system in the metacestode cyst wall, which is remarkable given the lack of motility of this larval stage, and the lack of serotoninergic and cholinergic elements. We propose that it could function as a neuroendocrine system, derived from the nervous system present in the bladder tissue of other taeniids. The detailed description of the development and anatomy of the protoscolex neuromuscular system is a necessary first step toward the understanding of the developmental mechanisms operating in these peculiar larval stages.

First Case of &lt;i&gt;Echinococcus multilocularis&lt;/i&gt; Infection in a Zoo-Housed Flying Squirrel (&lt;i&gt;Pteromys volans orii&lt;/i&gt;)

A 33 month-old male flying squirrel kept in a zoo developed progressive dyspnea and died. Macroscopically, the liver and lung were enlarged with numerous nodular vesicles. Histologically, these organs were replaced by numerous collapsed vesicles demarcated by fibrous tissues. The cysts lined by a cellular, germinal layer contained numerous brood capsules with abundant production of well-developed protoscolices. Protoscolices were about 80-100 μm in diameter, and had hooks being visible as refractive structures. This zoo locates in the east of Hokkaido where is an endemic area of Echinococcus multilocularis infection. From epidemiology and pathological findings, this animal was diagnosed as E.multilocularis infection. This report describes the pathology of the first case of E. multilocularis infection in a flying squirrel.

Co-infections of the cestode Echinococcus vogeli and the nematode Calodium hepaticum in the hystricomorphic rodent Agouti paca from a forest reserve in Acre, Brazil

The helminth fauna of Agouti paca (Linnaeus, 1766) has seldom been studied. In this paper, we report an unusual mixed infection of Echinococcus vogeli Rausch & Bernstein, 1972 and Calodium hepaticum (syn. Capillaria hepatica Bancroft, 1863) in free-ranging paca from a forested region in Acre (Brazil). Gross morphological examination revealed that paca liver contained multiple spherical to subspherical white or translucent lesions, which were isolated or frequently contiguous and partially covered by Glisson's capsule. Microscopic examination revealed unilocular cystic structures that contained abundant brood capsules in which numerous protoscolices budded from the inner surface. The protoscolices possessed rostellar hooks (33-41μm in length), a morphological characteristic of the blade and calcareous corpuscles that is consistent with the metacestode E. vogeli. The diagnosis of C. hepaticum infection was based on the morphology and morphometry of the egg-shaped ellipsoids with bipolar plugs (44.8±1.9μm (length)×24.4±2.0μm (width)) and liver histopathology. This finding expands the known range of C. hepaticum hosts in South America and, to the best of our knowledge, it is the first case of a mixed infection of E. vogeli and C. hepaticum. Furthermore, our data provide evidence that wild animal meat may be a source of C. hepaticum infection.

Comparative studies on the biochemical composition and polypeptide profiles of the cyst walls from sterile and fertile hydatid cysts of Echinococcus granulosus from buffalo host

Abstract In the present study, biochemical composition and polypeptide profiles of the cyst walls of sterile and fertile hydatid cyst, collected from the lungs of naturally infected Bubalus bubalis have been investigated. Significant quantitative differences in various biochemical components as well as in protein banding patterns were observed between the two types of cyst walls, suggesting variations in their metabolic states. The cyst wall collected from fertile cysts had significantly less glycogen, lipids and triglycerides but more RNA and DNA as compared to sterile cyst wall. Among phospholipid fractions, lysophosphatidylethanolamine and phosphatidylethanolamine were significantly higher in the fertile, whereas, sphingomyelin showed higher values in the sterile cyst wall. The numbers of polypeptides resolved in the fertile cyst wall were more than those in sterile cyst wall possibly due to the presence of extra proteins required for production of brood capsules and protoscoleces. Detection of more polypeptides by silver than CBBR-250 staining could be due to high sensitivity of silver stain which also detects conjugated proteins such as lipo-, phospho- and glycoproteins. The characteristic polypeptides specific to either types of the cyst wall have the potential to be exploited for diagnostics.