Immunodiagnosis of human hydatid disease: Where do we stand?

Update on the Seroepidemiology of Human Cystic Echinococcosis and Associated Risk Factors in Iran: A Systematic Review and Meta-Analysis

Background and Aims

Cystic echinococcosis (CE) poses a significant public health challenge in developing countries, including Iran. This systematic review and meta-analysis aim to enhance our understanding of CE prevalence by providing an updated assessment of the general prevalence of human CE in Iran through a comprehensive review of the literature.

Methods

PubMed, Scopus, Web of Science, Google Scholar, Magiran, and Scientific Information Database (SID) databases were searched for relevant literature published between January 1990 and December 2023. All peer-reviewed original papers evaluating the seroprevalence of human CE were included. Meta-analysis was performed using a random-effects model with 95% confidence intervals (CIs). Heterogeneity among the included studies was assessed using Cochran's Q and I 2 tests. The funnel plot and Egger's test were used to evaluate potential publication bias.

Results

Sixty-eight studies met the inclusion criteria. The overall seroprevalence of human CE in Iran's general population was 4% (95% CI 3%-6%). Significant differences in seropositivity to human CE were observed among age groups, urban versus rural residence, diagnostic methods, and in relation to the presence of dogs at home or on farm. Substantial heterogeneity was observed across the included studies (I 2 = 99.47%; p < 0.001). The funnel plot and Egger's test revealed considerable publication bias (Egger's test; p < 0.001).

Conclusion

Our findings demonstrate that CE remains prevalent in Iran, necessitating intensified health interventions and the development of targeted strategies for prevention and control. Recommendations include deworming dogs with praziquantel and vaccination of sheep with recombinant EG95 protein, removing raw offal or carcasses from the diet of dogs, hand washing, fencing of slaughterhouses with offal disposal systems, community participation for the control program and screening strategies for the diagnosis of asymptomatic cases and their timely treatment.

Cardiac Hydatid Cyst in a 34-Year-Old Ethiopian Woman With Heart Failure

Although the majority of hydatid cysts are found in the liver and lungs, cardiac hydatid cysts, particularly those in the left ventricle and interventricular septum, pose unique challenges because of their extremely rare manifestation of cystic echinococcosis, critical location, and potential for serious complications. Although uncommon, a hydatic cyst of the heart should be investigated in a patient with an intracardiac mass-particularly if it is cystic-and in a patient with symptoms of heart failure caused by a mass shown in imaging examinations. We present a case of left ventricular hydatid cyst in a 34-year-old woman who had been complaining of worsening dyspnea, shortness of breath, orthopnea, and cough for 3 weeks.

A ten-year evaluation of central nervous system cystic echinococcosis in a highly endemic area of Iran: Molecular epidemiology and clinicopathological characteristics

Cystic echinococcosis can involve various organs in humans with the brain and spine being particularly vulnerable. This research aimed to study clinicopathological features and molecular analysis of the central nervous system (CNS) echinococcosis cases in a central hospital for hydatid cyst surgery in northeastern Iran. CNS echinococcosis cases from surgically managed human CE cases at Ghaem hospital in northeastern Iran were analyzed from 2012 to 2022. Demographic and clinicopathological data were collected for CNS echinococcosis cases and formalin-fixed paraffin-embedded (FFPE) blocks were used for molecular analysis. The total prevalence of CNS echinococcosis cases was 1. 8 %. Most of the CE cases were reported in women (64. 7 %) and from rural areas (58. 8 %). The highest number of cases (41. 2 %) were aged ≤18 years, with majority being ranchers (47. 1 %). Thirteen cases (76.5 %) were found to have cysts in their brain, particularly in the supratentorial site. Headache was the most commonly reported sign in cases (9/13, 69.2 %). Infiltration of eosinophils, polymorphic inflammatory cells, and giant cells, gliosis, and foreign body granulomatous reaction, along with mild infiltration of mononuclear cells showing degeneration and necrotic foci in the brain infections. Spine infections included bone cartilage, ligaments, and hydatid cyst wall fragments. PCR analysis conducted on 17 samples revealed the presence of 13 isolates of E. granulosus sensu lato. Among these, 11 were classified within the E. granulosus sensu stricto (G1 and/or G3) complex, while 2 isolates were identified as belonging to the E. canadensis G6/G7. Cerebrospinal infection is a significant aspect of CE cases in northcentral Iran, with a higher prevalence among women and in rural areas. Children were the most affected age group, with the E. granulosus s.s. genotypes being the most common.

Hydatid Cysts of the Psoas Muscle: Insights from the Past Five Years

Echinococcosis represents a major public health issue and continues to be endemic in various regions around the world. Hydatid cysts are commonly located in the liver (primary site), followed by the lungs (secondary site). However, they are also found in less typical organs such as the spleen, kidneys, peritoneum, retroperitoneum, pancreas, gallbladder, and various other organs, as well as in striate muscles. Hydatid cysts involving the psoas muscle are rare, and in the past five years, only a few articles have addressed this condition due to its low incidence. Symptoms can be quite vague, and serological testing might return negative, making imaging studies crucial for an accurate diagnosis. Treatment options involve surgery alongside antiparasitic agents. Despite having a low mortality rate, the recurrence of hydatid disease remains high. This paper aims to provide new clinical data through our case presentation, while also offering a review of the cases of hydatid cysts involving the psoas muscle that have been published over the past five years.

An unexpected case of an adnexal hydatid cyst in a pregnant woman: a case report

BACKGROUND

Cystic echinococcosis, also known as hydatid disease, is a chronic and endemic illness caused by infection with a parasite called Echinococcus granulosus. In Romania, this disease has an incidence rate of 5.6 per 100,000 individuals, which is the highest in the Dobrogea region. The liver is the most affected site, accounting for 68.8% of cases, followed by the lungs at 17.2%. While cases of hydatid disease in the genital organs are rare, occurring at an incidence rate of only 0.5%, it is worth noting that cases of this disease in pregnancy worldwide are also rare, occurring at an incidence rate of 1 in 20,000 to 1 in 30,000 pregnancies.

CASE REPORT

A 15-year-old Eastern-European woman who was 12 weeks pregnant presented to the emergency room with acute pelvic pain, dysuria, and frequent urination. Her laboratory tests showed that she had a urinary tract infection, and pelvic ultrasound revealed that she had a mass on her right adnexa. Despite receiving treatment, her symptoms did not improve, and she had to undergo surgery to remove the mass, which turned out to be a hydatic cyst. She also had to undergo a cesarean section to deliver her baby owing to fetal distress during labor.

CONCLUSIONS

This medical case report provides a detailed description of a pelvic hydatid cyst that was discovered during pregnancy. What makes this case particularly noteworthy is the cyst's unusual location-it was found at the level of the right broad ligament of the uterus. Despite the complexity of the situation, the patient was able to receive effective treatment and the cyst was successfully managed with great outcomes for both the patient and the newborn. We hope that this report serves as a valuable example of how medical professionals can navigate challenging cases and provide optimal care for their patients.

Endobronchial Inflammatory Myofibroblastic Tumour Masquerading as a Ruptured Hydatid Cyst

Inflammatory myofibroblastic tumours (IMTs) represent a rare group of neoplastic lesions characterized by a diverse clinical presentation. Endobronchial involvement is infrequently reported, and its manifestation mimicking the symptoms of a ruptured hydatid cyst adds an additional layer of complexity to the diagnostic challenge. This case report delves into an exceptional clinical scenario where an endobronchial IMT masqueraded as a ruptured hydatid cyst, initially confounding the diagnostic team. Through a detailed examination of the patient's clinical history, radiological imaging, bronchoscopy findings and subsequent histopathological analysis, we aim to contribute to the existing medical literature and shed light on the nuances encountered in accurately identifying and differentiating these two entities.

Primary Pelvic Hydatid Cyst in Adolescent Female

Primary pelvic hydatid cyst occurs through hematogenous or lymphatic route. Adolescent female presented with complaints of suprapubic discomfort and constipation. Imaging revealed a cystic lesion in pouch of Douglas and removed surgically. This case emphasizes considering hydatid disease as a differential diagnosis of cystic pelvic mass, especially in the endemic regions.

Does the expression of granzyme B participate in inflammation, fibrosis, and fertility of hydatid cysts?

Echinococcus granulosus (sensu lato), a cestode that is endemic in Egypt, causes cystic echinococcosis (CE), a significant but neglected zoonotic disease that is prevalent throughout the world. Infected hydatid cysts are classified as fertile or non-fertile based on the presence of protoscoleces; nevertheless, the mechanism of non-fertile CE cysts remains unknown. The study aimed to assess whether granzyme B (GrB) expression and CD4 + /CD8 + could be related to the induction of non-fertile CE cysts. A total of fifty-eight individuals diagnosed with visceral hydatid cysts were selected, and they were further divided according to cyst fertility into fertile and non-fertile. Immunohistochemistry for CD4, CD8, and GrB was done. According to the results, hydatid cysts are common in adults and have no gender preference. The same clinical and laboratory data were shared by patients with fertile and non-fertile cysts (p = 0.186). GrB expression was not impacted by the fibrous deposition inside the hydatid cyst wall (p = 0.85); however, GrB was significantly correlated with the inflammatory density (p = 0.005). GrB expression was also found to be significantly higher in non-fertile cysts (p = 0.04). GrB expression is positively correlated with CD4 and CD8 expression. In conclusion, the expression of GrB in hydatid cysts may exacerbate the inflammatory response and impede cyst fertility while not affecting the fibrous deposition in the cyst wall.

Hydatid Disease of the Liver

Background

Echinococcosis also known as hydatid disease is a zoonotic parasitic disease caused by a tapeworm. It has a worldwide distribution. For long, it was thought to be a problem of the poorly sanitized "third world" and not given the importance it deserved. However, its occurrence in countries like Australia and New Zealand and recently in countries in Central Europe has meant that it is included in a WHO list of neglected diseases, has recently been the subject of extensive epidemiological studies, and has been the recipient of increased research funding.

Summary

The diagnosis is still based on clinical presentation in an endemic area corroborated with typical findings on imaging which routinely include ultrasound and CT scan. Serological tests have been used in some centers to support the diagnosis. Treatment depends on the site of involvement and can vary from wait and watch to extensive radical surgical procedures. The common element of all treatments is the addition of albendazole which forms an essential cornerstone of all treatment protocols. Inspite having been used for a fairly long time, there is still no consensus on the dose, duration, and timing of therapy with albendazole.

Key Message

Hydatid disease continues to be a significant global health problem inspite of a good understanding of its life cycle and rising standards of public sanitation. Though diagnosis is straightforward and not expensive, treatment can sometimes be complicated. The addition of albendazole to all treatment protocols is an important advance, but firm guidelines on duration of its use are still awaited.

Synchronous Left Ventricular and Endocranial Mass

Myocardial cysts represent a miscellaneous and infrequent spectrum of conditions, with each of them coming from a different etiological background. Congenital myocardial cysts, neoplasia, cysts of infectious origin (bacterial, viral, or parasitic), and cardiac pathologies that may fake cystic content are all encompassed in this group. Although most patients are asymptomatic, some may occasionally present with obstruction, valvular dysfunction, or heart failure. Even more uncommon is the coexistence of a myocardial cyst with other extracardiac locations causing extracardiac symptoms. In this direction, the coexistence of a myocardial and endocranial cyst is extremely rare and can cause symptomatology from the affected organs (e.g., seizures). Cardiac investigation in this context is mainly dependent on non-invasive diagnostic modalities, and laboratory procedures. In this case report, we present a 26-year-old Congolese male admitted with dyspnea and epileptic seizures. Echocardiography revealed left ventricular and both mitral and tricuspid valve dysfunction and the presence of two myocardial cysts, while brain computed tomography showed an additional frontal cystic lesion. A precise diagnostic workup with a combination of non-invasive imaging, laboratory results, and epidemiology data assisted the diagnosis and guided the most suitable therapeutic choice.

Hospital-based retrospective analysis of 224 surgical cases of lung hydatid cyst from southern Iran

BACKGROUND

The lungs are considered the second-most frequent location for hydatid cyst in human. The current retrospective hospital-based study aimed to assess the epidemiological data, clinical presentation, and treatment outcomes of lung hydatid cyst in patients who underwent surgery for this disease in Fars province, southern Iran.

METHODS

In this retrospective study, hospital records of 224 pulmonary hydatid cyst patients were assessed in two main university-affiliated hospitals in Fars Province, southern Iran. Clinical features of patients, epidemiological data, cyst features, surgical interventions, and treatment outcomes were reviewed and analyzed.

RESULTS

A total of 224 hydatid cyst cases of the lung were reviewed. Male patients accounted for the majority of cases (60.4%). The average age of the patients was 31.13 (± 19.6), ranging from 2 to 94 years old. Of the 224 patients, 145 (75.9%) cases had only one single cyst and mostly 110 (53.9%) located in the right lung. Also, 6 (2.9%) cases had cysts in both lungs. The lower lobe of the lungs was the most common location of the hydatid cyst. The average size of lung hydatid cyst was 7.37 cm (SD = 3.86; rang: 2-24) while for the cyst areas was 42.87cm2 (SD = 52.76; range: 2-488). Regarding the surgical method, 86 (38.6%) cases were operated by lung resection surgery while 137 (61.4%) cases had lung preserving one. The chief complaints of the patients were cough (55.4%) and dyspnea (32.6%). Relapse was documented in 25 (11.16%) of cases.

CONCLUSIONS

Lung hydatid cyst is a common infection in southern Iran. Lung preserving surgery is the method of choice for the management of hydatid cyst. Relapse, which was not uncommon in our study, is a challenging feature of hydatid cyst management.

Molecular characterization and serodiagnostic evaluation of the Echinococcus ortleppi recombinant glutaredoxin 1 protein for cystic echinococcosis in buffalo (Bubalus bubalis)

Cystic echinococcosis (CE), caused by the metacestode of Echinococcus granulosus sensu lato (s.l.), adversely affects the physiology of the vital organs in which they grow. Condemnation of meat causes substantial economic loss to the livestock industry. Conventionally the infection is detected by necropsy as serological diagnosis of the infection in livestock is ambiguous. Identification of specific diagnostic antigens would be a substitute for the cyst fluid antigens which lack adequate diagnostic sensitivity and specificity. BLAST analysis supported by the negligible pairwise nucleotide distance of the 389 nt COX1, 489 nt NAD1, and 425 nt ITS1 with the related sequences of E. ortleppi ascertained the association of E. ortleppi with CE in buffaloes. Given the extensive distribution of glutaredoxin 1 in every developmental stage of Echinococcus granulosus s.l that makes it an ideal serodiagnostic antigen for CE, we expressed the 14 kDa E. ortleppi glutaredoxin 1 (rEoGrx1) protein in E. coli BL21 (DE3) and tested a total of 225 sera samples, including 126 sera samples from the necropsy-positive buffalo, by the rEoGrx1 IgG-ELISA. The ELISA could detect a total of 82/126 sera samples as positive. The diagnostic sensitivity and specificity of the rEoGrx1 IgG-ELISA were 65.1 % and 51.5 %, respectively. The protein showed serological cross-reaction against Fasciola gigantica, Toxoplasma gondii, and Sarcocystis sp. The in silico bioinformatics analysis of the E. ortleppi, F. gigantica, and T. gondii glutaredoxin sequences revealed fully conserved amino acids at positions 11 and 21, the substitution of conserved amino acids at positions 14 and 6, and semi-conserved substitutions at positions 3 and 4, respectively. The findings partly explain the molecular basis of the serological cross-reactivity of the protein.

Pulmonary Hydatid Cyst in Children and Adults: Diagnosis and Management

Hydatid cyst disease induced by Echinococcus granulosus is a parasitic disease known since ancient times. Today, it continues to be seen in many countries and creates serious problems. The lung is the second most frequently affected organ by hydatid cysts after the liver. Lung involvement is more prevalent in children than adults, and the growth of the cyst is faster in children. Hydatid cysts are mostly seen in the right lower lobe of the lung. Common symptoms are chest pain, cough, and shortness of breath, with the most diagnostic symptom being the expectoration of cyst fluid or membranes. In endemic areas, the diagnosis of hydatid cysts can usually be made easily by clinical findings, serology tests, and radiological findings. When the hydatid cyst ruptures and becomes complicated, it is clinically and radiologically confused with many diseases, especially lung cancer. Surgery is accepted as primary treatment of lung hydatid cysts all over the world. The surgical approach is related to several factors such as the size of the cyst, whether it is intact or complicated, unilateral or bilateral, solitary or multiple, and the presence of destruction of the lung parenchyma. Although it is stated by some surgeons that capitonnage is not required, the most frequently applied surgical technique is cystotomy and capitonnage. Pulmonary resection should be avoided as much as possible, particularly in children. Albendazole or mebendazole treatment in pulmonary hydatid cyst is generally used after surgery and to prevent recurrences.

Serological Follow-up of Human Cystic Echinococcosis in the Thrace Region, Turkey

Background

Parasites of the genus Echinococcus are common worldwide and are important cestodes that cause serious infections in humans and animals. This retrospective study evaluated the indirect hemagglutination (IHA) test results of serum samples obtained from patients with a pre-diagnosis of cystic echinococcosis (CE) within ten years. In addition, the role of the IHA test results of the patients in the follow-up of the treatment and determining possible recurrences was investigated.

Methods

The IHA test results of 2426 serum samples of patients with a pre-diagnosed CE admitted to Trakya University Health Center for Medical Research and Practice in Edirne, Turkey, between January 2011 and December 2020 were evaluated retrospectively. The data of 53 patients with CE who had medical treatment and/or postoperative follow-up serological records were evaluated.

Results

Of 2426 IHA tests, 376 (15.5%) were seropositive, and 2050 (84.5%) were seronegative. It was determined that 376 serum samples detected as positive belonged to 207 patients with CE. Of 207 CE patients, 109 (52.7%) were female and 98 (47.3%) were male. The most common organ involvement was the liver in 186 (89.9%) cases. Of 53 patients, 16 were considered relapse cases. The median follow-up period for 16 recurrent cases was 31.8 (1-77) months. Our results showed a statistically significant correlation between long-term serological follow-up and recurrence detection (P=0.034).

Conclusion

Long-term serological follow-up after treatment is considered useful in determining possible recurrent cases. CE is an important public health problem for endemic regions, including our country, and we think our study results will contribute to the status and follow-up of the disease.

Serosurvey of Cystic Echinococcosis and Related Risk Factors for Infection in Fars Province, Southern Iran: A Population-Based Study

Cystic echinococcosis (CE) is a common zoonotic infection in all provinces of Iran, especially in areas where people live on agriculture and animal husbandry. The current cross-sectional population-based study is aimed at determining the seroprevalence of CE in Kavar County, Fars province, southern Iran. Blood samples were collected from 1500 individuals (749 males and 751 females). Anti-hydatid cyst antibodies were detected, using a recombinant B8/1 antigen of Echinococcus graunlosus in an ELISA system. Multivariate logistic regression analysis was used to find out the independent risk factor for CE seropositivity. Anti-hydatid cyst antibodies were detected in the sera of 131 out of 1500 participants, corresponding to a seroprevalence rate of 8.73%. With a statistically significant difference (p < 0.05), the seroprevalence of hydatid cyst in males and females was 5% and 7%, respectively. Differences in the seropositivity of hydatid cysts were also statistically significant by occupation (p < 0.05). The seroprevalence of hydatid cyst was significantly higher in the age group of 35-45 years than in other age groups (p < 0.05). Multivariate logistic regression showed that only age was associated with seropositivity to CE (OR = 2.23, 95% CI: 1.33-3.72). Moreover, there was a statistically significant association between seropositivity to hydatid cysts and underlying diseases such as hypertension (p = 0.049) and fatty liver (p = 0.048). The findings of this study indicate that the seroprevalence rate of CE is relatively high in the Fars province, southern Iran, and this high rate of infection is mainly linked to people's jobs and lifestyles.

Turkish HPB Surgery Association consensus report on hepatic cystic Echinococcosis (HCE)

OBJECTIVES

Cystic Echinococcosis (CE) is one of the important problems of the Eurasian region. We aimed to prepare a consensus report in order to update the treatment approaches of this disease. This study was conducted by Turkish HPB Surgery Association.

MATERIAL AND METHODS

This study was conducted with the modified Delphi model. For this purpose, we conducted a three-stage consensus-building approach.

RESULTS

Six topics, including diagnosis, medical treatment, percutaneous treatment, surgical treatment, management of complications and posttreatment follow-up and recurrences in HCE were discussed.

CONCLUSION

The expert panel made recommendations for every topic.

Evaluation of two heterologous recombinant antigens for the serological diagnosis of human polycystic echinococcosis

Polycystic echinococcosis (PE) is a zoonosis endemic in the Neotropical region of the Americas. It is caused by the larval stage of the cestode Echinococcus vogeli, which develops as harmful cysts that slowly grow in the liver, lungs and other organs of humans and other host species. Human PE diagnosis is usually based on clinical and epidemiological aspects and imaging techniques, often requiring confirmation by immunological assays. The currently available serological tests for detecting antibodies against Echinococcus spp. are mostly based on complex, variable and poorly characterized mixtures of native parasite antigens, which impairs specificity and/or sensitivity. In this scenario, the evaluation of well-characterized alternative antigens is urgently needed for the improvement of PE diagnosis. Here, two subunits (AgB8/1 and AgB8/2) of the major secretory antigen from Echinococcus granulosus (antigen B (AgB)), of diagnostic value for cystic echinococcosis, were validated for PE diagnosis. These antigens, produced as pure recombinant proteins (rAgB8/1 and rAgB8/2) in Escherichia coli, allowed detecting specific immunoglobulin G antibodies in sera from PE patients in an enzyme-linked immunosorbent assay, with sensitivities of 83.72% and 81.40%, respectively, and specificities of 83.12% and 80.09%, respectively. The use of recombinant proteins overcomes difficulties to obtain parasite material and reduced non-specific reactions and costs. Our results demonstrated reproducibility and accuracy high enough to be considered valid according to the acceptance criteria for Food and Drug Administration assay validation. This qualifies rAgB8/1 and rAgB8/2 as potential substitutes for the currently used parasite crude or partially purified antigens.

Comparison of the multi-epitope recombinant antigen DIPOL and hydatid fluid for the diagnosis of patients with cystic echinococcosis

The use of serological tests containing multiple immunodominant antigens rather than single antigens have the potential to improve the diagnostic performance in Cystic Echinococcoses (CE) as a complement tool to clear the inconclusive imaging data. Here, we comparatively evaluated the diagnostic value of Hydatid Fluid (HF) and the recently described recombinant multi-epitope antigen DIPOL in IgG-ELISA in a clinically defined cohort of CE patients. The serum samples from 149 CE patients were collected just before surgical or Percutaneous- Aspiration- Injection- Reaspiration (PAIR) procedures. Additionally, serum samples of patients with other parasitic infections (n=49) and healthy individuals (n=21) were also included in the study as controls. To investigate the association between the genotype of the parasite and DIPOL, cyst materials from 20 CE patients were sequenced. In terms of overall sensitivity, HF was higher than DIPOL (82.55%,78.52%, respectively). However, while the sensitivity of HF was higher than DIPOL in patients with active and transitional cysts (83.3%, 75.4%, respectively), sensitivity of DIPOL in inactive cysts was higher compared to HF (95.6%, 78.3%, respectively). The sensitivity of DIPOL depending on cyst stage was statistically significant (P= 0.041). In terms of specificity, DIPOL was found to be better than HF (97.71%, 91.43%, respectively). By genotyping, the majority of 20 patients showed G1 genotype (80%). All patients harboring G3 and G1/G3 cyst genotypes were positive with both antigens, while 87.5% of patients with G1 genotype were seropositive with HF and 75% with DIPOL. The overall sensitivity and high specificity of DIPOL suggest that this recombinant protein containing immunodominant epitopes is a potential substitute for the HF by serological tests for the diagnosis of CE.

Hydatid disease as a rare cause of neck swelling: Two cases report

INTRODUCTION

Despite the fact that hydatid disease is endemic in some countries, its cervical location remains very rare.

PRESENTATION OF CASE

We report two cases of primary cervical hydatid disease in two children from rural areas. The imaging was not specific, since the location is rare; the diagnosis was only confirmed after surgery.

DISCUSSION

Hydatid cyst is a rare pathology. Thus clinical presentation, radiological examinations, fine needle aspiration and serology can be useful to suspect the diagnosis.

CONCLUSION

Hydatid disease should be considered when dealing with slow-growing renitent neck swelling in endemic countries.

Determining the Frequency of Cystic Echinococcosis among Suspected Cases Referred to Health Centers Southwest Iran, and Post-Treatment Serologic Follow-up

Background:

This study was designed to determine the frequency of hydatidosis in Khuzestan Province, Iran and to evaluate the antibody changes in infected individuals after treatment.

Methods:

Overall, 454 sera were collected from health centers of Khuzestan Province, southern Iran (from 2013 to 2018). Demographic data such as age, gender and history of disease were recorded. Serum samples were investigated for antibody against CE by ELISA using antigen B. Thirty six of cases were followed up after treatment.

Results:

Among the 454 evaluated cases, antibody against CE was detected in 184 (40.52%) including 115 (62.5%) females and 69 (37.5%) males. Age distribution was from 8–97 yr, the highest prevalence of hydatid cyst was observed in age group 40–49 years. Liver was the most infected organ (76.63%). Relapse of CE occurred in 23 of patients. In the majority of patients the antibody decreased, whereas in some cases increased CE antibody observed during post-treatment follow up.

Conclusion:

Current study indicated the high prevalence of hydatidosis and rate of relapse after treatment among suspected patients. Therefore, long periods and regular follow-up of patients after treatment is necessary and for these monitoring, antibody assay can be an appropriate method.

Screening of Cystic Echinococcosis and Toxocariasis in Urmia Municipal Workers, Northwest Iran

BACKGROUND

Echinococcus granulosus and Toxocara spp., the causative agents of hydatid cyst and toxocariasis in humans and animals, are zoonotic infections with medical and veterinary significance respectively.

AIM

Herein, we aimed to investigate the seroprevalence of toxocariasis and cystic echinococcosis in Urmia municipal workers (gardeners and sweepers) in 2018 using ELISA assay.

OBJECTIVE

There is no precise report on the seroprevalence of toxocariasis and cystic echinococcosis in Urmia municipal workers using ELISA assay. Therefore, this study found an opportunity to investigate this subject.

METHODS

A total of 220 blood samples were obtained from municipal workers with an average age of 41.31 ± 9.42. Commercial anti-Toxocara canis and hydatid cyst ELISA kits were used to assess the seroprevalence rates.

RESULTS

Approximately, 14.5% and 2.3% of individuals were seropositive for toxocariasis and hydatidosis, respectively. Consuming unboiled milk and/or raw/uncooked meat and rural conditions are risk factors for toxocariasis. Regarding hydatidosis, consuming unwashed vegetables was the only statistically significant risk factor. Toxocara infection (p = 0.01), but not hydatid cyst (p = 0.05), is more prevalent among sweepers than municipal gardeners.

CONCLUSION

Due to the occupational condition of municipal workers, they are exposed to many infectious agents; thus, more researches should be done on these populations.

Echinococcosis of the spine

Echinococcosis or hydatid disease affecting the spine is an uncommon manifestation of Echinococcus granulosus infection of the spine.More commonly found in endemic areas, it causes significant morbidity and mortality as it grows slowly and produces symptoms mainly by compressing the spinal cord.As diagnostic methods are non-specific, diagnosis and management are usually delayed until the disease is advanced, thereby therapy is usually unlikely.Treatment is usually surgical, aiming at cyst excision, spinal cord decompression and spinal stabilization.This article summarizes the clinical findings of echinococcosis of the spine, discusses the specific laboratory and diagnostic findings, lists the current treatment options, and reviews the patients' outcomes.The aim is to prompt clinicians to be aware of the possibility of echinococcosis as a possible diagnosis in endemic areas. Cite this article: EFORT Open Rev 2021;6:288-296. DOI: 10.1302/2058-5241.6.200130.

Extra-hepatopulmonary cystic echinococcosis in Bulgaria: frequency, management and outcome of the disease

In the endemic countries, human cystic echinococcosis (CE) poses a serious medical and social problem. Because it most often affects the liver and lungs we aimed to define the proportion of cases with different organ localization, the diagnostic and therapeutic approaches in such cases, and the outcome of them. For a period 2010-2019, a total of 2863 cases of CE were registered in Bulgaria, of which 148 (5.17%) with organ localization other than liver and/or lung. The majority of patients with extra-hepatopulmonary localization of CE were adults. The distribution by gender showed predominance of female patients (57.43%) over those of males and primary cases (85.14%) exceeded the cases of recurrence. According to our study most common is the spleen involvement, followed by involvement of the abdominal cavity, kidneys and muscle/subcutaneous tissue. Other extra-hepatopulmonary organ localizations are significantly less common. This study shows that the extra-hepatopulmonary localization of CE is not so rare, and in most cases it is a primary disease. In respect of this, clinicians should consider hydatidosis in the differential diagnosis when cystic formation(s) is found, regardless of the organ involved.

Promising proteins detected by Western blot from Echinococcus granulosus protoscoleces for predicting early post-surgical outcomes in CE-affected Tunisian children

BACKGROUND

Cystic echinococcosis (CE) affects predominantly young patients in highly endemic areas. Improved serological methods are needed for the follow-up of CE cases, especially given the high rates of post-surgical relapse that require detection as soon as possible.

METHODS

We designed a study to investigate the value of antigenic proteins extracted from Echinococcus granulosus (E. granulosus) protoscoleces, and of recombinant B2t and 2B2t proteins, for assessing the efficacy of surgical treatment carried out on CE-affected children. This study was performed on 278 plasma samples collected from 59 Tunisian children surgically treated for CE and monitored for 3 years post-surgery. The patients were classified according to post-surgical outcomes into a "non-relapsed" (NRCE) and a "relapsed" (RCE) group. We performed in-house ELISAs to measure anti-B2t and anti-2B2t IgG and immunoblotting for the detection of IgG against SDS-PAGE-resolved E. granulosus protoscoleces-specific antigens. The Wilcoxon test was applied to assess anti-B2t and anti-2B2t IgG levels. We applied the Cochran Q test to compare the distribution of immunoblotting antigenic bands between 1-month and 1-year post-surgery.

RESULTS

The probability of being "relapse-free" when a decrease in antibody titers occurred between 1 month and 1 year post-surgery was 81% and 75%, respectively, for anti-B2t and anti-2B2t IgG. We identified five protoscolex protein bands of 20, 26/27, 30, 40 and 46 kDa as highly immunoreactive by immunoblot for both RCE and NRCE patients at 1 month post-surgery, and significantly lower immunoreactivity after 1 year (p < 10^-4) for NRCE compared to RCE patients. The proteins at 26/27 and 40 kDa displayed the best performance in predicting the outcome, with an 84% probability of being relapse-free when the reactivity against the 40 kDa antigen, the doublet at 26/27 kDa, or both was absent or disappeared between 1 month and 1 year post-surgery, and a 93% probability of being relapsed when both bands remained reactive or increased in intensity between the two time points.

CONCLUSIONS

The B2t protein could be useful for the prediction of CE early post-surgical outcomes. The proteins of E. granulosus protoscoleces, especially the doublet P26/27 and P40, could be promising predictive biomarkers for the post-surgical follow-up of CE cases as well.

Seroprevalence of Cystic Echinococcosis Using Recombinant Antigen B-ELISA in North Khorasan Province, Northeast of Iran

Background

Cystic echinococcosis (CE) is one of the most important helminthic parasitic diseases in Iran. The current study aimed to assess the seroprevalence of CE in North Khorasan Province, Northeast of Iran in 2018.

Methods

The study was carried out in seven cities of North Khorasan Province. Venous blood samples were collected from 932 individuals referring to health centers of those seven cities. A questionnaire was used to obtain the data regarding the subject's gender, age, residence and risk factors linked to the hydatid cyst. Sera samples were evaluated for anti-hydatid cyst antibodies in an ELISA system, using a recombinant B8/1 antigen of E. granulosus.

Results

Of the 932 recruited subjects, 496 (53.2%) were male and 436 (46.8%) were female. The range of participants' age was between 11 to 83 yr old and the mean age of the subjects was 35.4 (±12.7) years. Anti-hydatid cyst antibodies were detected in the sera of 37 out of 932 subjects, corresponding to a seroprevalence rate of 3.96%. From these, 20 (54.05%) were male and 17 (45.95%) were female. There were no associations between seropositivity to hydatid cyst and age, the gender of the participants, residential areas and having contact with dogs (P>0.05).

Conclusion

CE is relatively prevalent throughout the North Khorasan Province in the Northeast of Iran. Rate of CE infection in this Province is somewhat similar to the rate of infection in other parts of the country.

Robot-Assisted Nephron-Sparing Surgery of Renal Hydatid in Pregnancy: A Predicament in Management

Background: Hydatid disease is a parasitic zoonosis caused by Echinococcus granulosus. Dog and other carnivores are the definitive hosts, which harbor adult worm. Humans are the accidental and dead-end hosts that acquire the infection by ingestion of eggs released from the intestinal tract of these carnivores, mainly dogs. The primary organ of echinococcosis in humans is the liver and lung, while the kidney is the third most commonly involved organ. Occurrence of hydatid disease of kidneys in isolation or with multiple organ involvement and their management has been reported and well described. The concurrent hydatidosis and pregnancy are an unusual clinical condition and poses a clinical challenge. Case Details: In this study, we present a case of 36-year-old woman with symptomatic hydatid disease of the right kidney during the first trimester of pregnancy. A multidisciplinary team discusses the pros and cons of hydatid during pregnancy with the patient. After taking informed consent from the patient, she was effectively managed by medical termination of pregnancy followed by robot-assisted laparoscopic pericystectomy. Conclusion: The co-occurrence of symptomatic renal hydatid and pregnancy is quite unusual. Medical or surgical management of hydatid during pregnancy can have some detrimental effect on the fetus. Hence these patients could be managed with medical termination of pregnancy followed by robot-assisted nephron-sparing surgery. Robot-assisted surgery for the renal hydatids is safe and effective, and has a shorter learning curve.

A case of human cystic echinococcosis acquired in Ireland

Cystic echinococcosis (CE) is caused by the cestodes of the Echinococcus granulosus sensu lato complex and, in the majority of cases, is associated with hepatic or pulmonary involvement. Human CE is not thought to be endemic in Ireland. We describe the first reported case of human CE possibly acquired in Ireland.

Cystic Echinococcosis: Clinical, Immunological, and Biomolecular Evaluation of Patients from Sardinia (Italy)

Cystic echinococcosis (CE), a zoonotic disease caused by the larval stage of the tapeworm Echinococcus granulosus sensu lato (s.l.), is a worldwide public health problem. Echinococcus granulosus sensu stricto (s.s.), associated with G1 and G3 genotypes, is endemic with high prevalence in the Mediterranean basin. The parasite's life cycle comprises definitive hosts (canids) and intermediate hosts (ruminants) and can occasionally involve humans. The main aim of this research was to confirm the diagnosis of 13 patients suspected of CE who presented different complications and needed the surgical removal of the cysts. We also wanted to understand and clarify more the diagnosis of echinococcosis in humans. For this purpose, the patients first underwent cyst evaluation by ultrasound (US), immunological analysis, and then total pericystectomy, followed by parasitological, histopathological, and molecular biology examinations of the cysts. US stadiated one CE1, one CE2, eight CE3b, one CE4, and two CE5; immunology evidenced nine positives; histopathology confirmed 11 CE cysts, of which 8 fertile presenting protoscoleces were identified as E. granulosus s.s. by molecular biology, genotyped as three G1 and four G3 by neighbor-joining (NJ) phylogenetic tree. In conclusion, the results showed that 11 patients were affected by E. granulosus s.s. G1 orG3, and 2 cystic neoformations were of non-parasitic origin.

Serodiagnosis of human cystic echinococcosis based on recombinant antigens B8/1 and B8/2 of Echinococcus granulosus

BACKGROUND

Cystic echinococcosis (CE) is a widespread parasitic disease caused by the larval stage of Echinococcus granulosus. Since current methods for the diagnosis of CE are not efficient enough, rapid, and reliable tests are required for the acceleration of CE diagnosis. The present study aimed to produce recombinant B8/1 and B8/2 antigens of E. granulosus and evaluate their sensitivities and specificities separately and simultaneously for the diagnosis of CE.

METHODS

The recombinant B8/1 and B8/2 antigens were produced and used in an ELISA system for the diagnosis of CE. The sera specimens including 30 sera from pathologically confirmed CE patients, 30 from other non-CE patients, and 30 from healthy controls, were evaluated by the ELISA, using AgB8/1 and AgB8/2.

RESULTS

The results showed a sensitivity of 93.33%, 90%, and 96.7% for AgB8/1, AgB8/2, and their combination, respectively. The specificities were 91.7%, 93.33%, and 93.33% for AgB8/1, AgB8/2, and their combination, respectively.

CONCLUSION

Simultaneous usage of AgB8/1 and AgB8/2 increased the test sensitivity for the diagnosis of CE. Furthermore, the specificity of AgB8/1 and AgB8/2 combination was more than AgB8/1 and equal to AgB8/2 alone. The findings revealed that the simultaneous usage of AgB8/1 and AgB8/2 could be a suitable approach for the diagnosis of CE.

Diagnostic performance of Echinococcus granulosus protoscolices antigens in the serodiagnosis of human cystic echinococcosis

The development of suitable serological tests for the diagnosis of CE is still necessary. This study aimed to evaluate the efficacy of ELISA in the diagnosis of human cystic echinococcosis (CE), using parasite protoscolices antigens. Liver hydatid cysts were isolated from sheep infected with hydatid cysts and the protoscolices were isolated from the hydatid cyst fluid. Protoscolices crude antigen was prepared by mechanical disruption, plus freeze-thawing and sonication methods. Thirty sera samples of confirmed hydatid cyst patients, 30 samples of healthy individuals, and 30 samples of people with other infections were collected and the samples were evaluated in an ELISA system, using the crude protoscolices antigen. The sera samples were also simultaneously evaluated by antigen B-ELISA. The estimated value of sensitivity and specificity for the ELISA, using the crude protoscolices antigens, was 93.3% (95% CI: 76.4-98.8%) and 90% (95% CI: 78.8-95.8%), respectively. These values were 86.6 (95% CI: 68.3-95.6) and 91 (95% CI: 80.81-96.9) for the antigen-B based ELISA. Antigens prepared from protoscolices of hydatid cyst are suitable candidates for the serologic diagnosis of human CE. Further studies are needed to identify a single specific antigen among the protoscolices antigens to improve the diagnostic performance of these antigens.

Sero-epidemiology of Hydatidosis Among General Population of Jolfa County, Northwestern Iran Using IHA, ELISA and Western Blot (2017-2018)

BACKGROUND

Human hydatidosis is mostly a latent and neglected disease with known endemicity in Iran.

AIMS

Due to the importance of this infection in the country and its latent nature, we aimed to evaluate the serological status of hydatid cyst in northwestern Iran.

OBJECTIVES

Herein, we evaluated the serological status of hydatid cyst in urban and rural inhabitants of Jolfa county, northwestern Iran during 2017-2018.

METHODS

In total, 1296 blood samples were obtained from human individuals and the presence of anti-E. granulosus antibodies was investigated using IHA, ELISA and WB.

RESULTS

Based on results, 25 IHA positive person were detected in the examined population, however ELISA test showed 14 of 25 IHA positive patients as negative. Also, 269 IHA negative fellows were shown as negative by ELISA. WB analysis of sera from 25 IHA positive subjects revealed consistent results with the ELISA test, and the most reactive SHCF Ag was a 37 KDa protein. The age-standardized seroprevalence of hydatidosis among Jolfa's general population was 1.12% with 95%CI: 1.02-1.20. Moreover, there existed a significant association between keeping/- contact with dogs (P = 0.022) as well as vegetable consumption (P < 0.001) with ELISA positive test results.

CONCLUSION

Along with such serological evidence in this region, we highly suggest physical examination and applying imaging techniques for suspected cases in the area for a better understanding of CE.

Human cystic echinococcosis: Serological diagnosis by indirect hemagglutination test, enzyme-linked immunosorbent assay, immunoelectrophoresis, and immunoblotting in surgically confirmed patients versus cases diagnosed by imaging techniques

INTRODUCTION

Human cystic echinococcosis (CE) diagnosis is based on imaging findings and serology. Serology is the first-line test followed by imaging tests.

MATERIALS AND METHODS

A total of 268 serum samples from CE patients were included in this study. The serodiagnosis was made simultaneously by indirect hemagglutination assay (IHA), enzyme-linked immunosorbent assay (ELISA), immunoblotting test (IB), and immunoelectrophoresis (IEP).

RESULTS

In serum samples belonging to surgically confirmed CE patients, we observed a percentage of positivity of 83.7% [77.2%-89.0%] and 80.7% [73.9%-86.4%] for IHA and IgG-ELISA, respectively. IgG-IB was associated with a higher positivity rate than IEP with 81.3% [74.6%-86.9%] and 62.0% [54.2%-69.5%], respectively. IHA and ELISA results were analyzed using cut-off generated by receiver operating curves. The best diagnostic performances were achieved by IHA (cut-off ≥1/128) and ELISA (>1.16 index). Sensitivities reported in patients with suggestive imaging findings and positive Echinococcus IB were 86.2% [78.0%-92.2%], 72.5% [62.8%-80.9%], 49.0% [39.0%-59.1%] for IHA, IgG-ELISA, and IEP, respectively. All tests gave false negative results in the confirmed CE group. Overall, 18.6% of negative results were obtained by IgG-IB test. Cross-reactivities with non-hydatid serum samples were observed in all tests. Only one patient carrying Taenia saginata serum cross-reacted with 8/12 kDa band by IB. We observed specificity at 73% [63.2%-81.4%], 87% [78.8%-92.9%], 99% [94.6%-100.0%], and 99% [94.6%-100.0%] with IHA, IgG-ELISA, IEP, and IgG-IB, respectively. Serology was less sensitive (74%) in lung cysts. Sensitivity was better in liver cysts, especially by IgG-IB (96%).

Comparison of the Utility of Recombinant B8/2 Subunit of the Antigen B, Native Antigen, and a Commercial ELISA Kit in the Diagnosis of Human Cystic Echinococcosis

BACKGROUND

Cystic echinococcosis (CE) is a helminthic disease caused by the larval form of Echinococcus granulosus. In the present study, the B8/2 subunit of antigen B (AgB) of E. granulosus was expressed in E. coli host and then applied in a diagnostic ELISA set up.

METHODS

The DNA sequence of AgB8/2 subunit from E. granulosus was extracted from the GenBank and codon-optimized according to E. coli codon usage. The target sequence was cloned in an expression vector (pGEX-4T-1). The produced antigen was used in an ELISA system, and its performance for the diagnosis of human hydatid cyst was evaluated, using sera from CE and non-CE patients, along with the sera from healthy subjects. Moreover, the diagnostic value of the recombinant protein was compared with native AgB, as well as with a commercial kit.

RESULTS

Antibodies to hydatid cyst were detected in 27 out of 30 patients corresponding to a sensitivity of 90% (95% CI: 73-98%). Cross-reaction with sera of non-CE subjects was seen in two cases resulted in a specificity of 93.5% (95% CI: 82-98%) for the test. A sensitivity of 87% and specificity of 90% were found for the native form of the antigen, while the ELISA commercial kit had a sensitivity of 97% and specificity of 95%.

CONCLUSION

Our data show that rEgAgB8/2 is an appropriate source of antigen for the serological diagnosis of human hydatid cyst. Co-expression of the rEgAgB/2 along with other subunits of AgB may enhance the performances of these antigens for the serodiagnosis of human CE.

Progress on the development of rapid diagnostic tests for foodborne neglected zoonotic helminthiases: A systematic review

BACKGROUND

Foodborne Neglected Zoonotic Helminths (FNZH) are parasites of both economic and public health importance. They include Taenia solium, Echinococcus granulosus sensu lato, Echinococcus multilocularis and Foodborne trematodes (FBT). FNZH are earmarked for major interventions for control, elimination and eradication. This systematic review highlights the progress towards development of rapid tests for the diagnosis of FNZH since 2010 when they were listed as neglected tropical diseases.

METHODOLOGY

A systematic search was conducted in three databases, World of Science, Embase and PubMed using the same search phrase. The search produced 480 hits. Three studies from back referencing were included. Only 22 of these met the inclusion criteria. Data was extracted from these and presented qualitatively.

RESULTS

Twenty-five rapid diagnostic tests were found to have been developed since 2010, eight for diagnosis of T. solium infections, eight for echinococcosis and nine for FBT infections. The rapid tests for diagnosing T. solium infections included six antibody detecting and two antigen detecting tests. They constitute a combination among them, with some tests providing qualitative, others quantitative results. Similarly, seven out of the eight rapid tests developed for Echinococcus infections were antibody detecting tests save for one loop mediated isothermal amplification test. All of them were qualitative tests. For FBT infections, nine rapid tests were described; two antibody and one nucleic acid detecting test for diagnosis of Fascioliasis; three nucleic acid detecting tests for Opisthorchiasis; one antibody detecting test for Paragonimiasis; and for Clonorchiasis, one antibody and one nucleic acid detecting test. The FBT infection rapid tests were all qualitative in nature. Most of these tests have not undergone field evaluation in endemic areas where they will be used most.

CONCLUSION

This review describes the development and evaluation of rapid diagnostic tests, while highlighting the need for in depth validations of the tools to determine how well they can perform in endemic areas.

Retrospective Study of Cystic Echinococcosis in a Recent Cohort of a Referral Center for Liver Surgery

BACKGROUND

Cystic echinococcosis (CE) is a zoonosis endemic in Spain caused by the larval stage of the cestode Echinococcus granulosus and is one of the 18 neglected tropical diseases recognized by the WHO. The aim of this study was to describe the epidemiological and clinical data of CE in a surgical referral hospital.

METHODS

A retrospective descriptive study of all adults' patients diagnosed with CE and followed at Vall d'Hebron University Hospital in Barcelona, Spain, between 2000 and 2015.

RESULTS

We found 151 cases, 78 (51.7%) women, and median age at diagnosis was 68 (range, 15-92) years. Diagnosis was a radiological finding in 97 (64.2%) and the most frequent location was the liver [135 (89.4%) patients]. Nearly 80% of the cysts were calcified and serology was positive in 48 (51.6%). The WHO-IWGE classification was only available in 70 of the 104 (67.3%) cases of liver cysts that had an ultrasound. First therapeutic plan was "watch and wait" followed by surgery. International recommendations were not always followed, particularly in CE4 and CE5 stages, and 20% needed a change of treatment because of progression or recurrence. Patients treated surgically were younger, more symptomatic, and had larger and less calcified cysts in multiple sites. Serology was not useful for CE diagnosis and neither serology nor calcification of the cyst helped to predict viability.

CONCLUSIONS

The formation of multidisciplinary teams in reference hospitals could help to improve CE diagnosis, its management, and follow-up, since international recommendations are not usually followed.

Seroprevalence of cystic echinococcosis in a high-risk area (Al-Mafraq Governorate) in Jordan, using indirect hemagglutination test

Hydatid disease (HD) is a zoonotic disease of humans and animals which is caused by infection with the larval stages of the taeniid cestodes of the genus Echinococcus. HD is endemic in many countries of the Middle East, including Jordan. The seroprevalence rate of HD in areas of elevated risk in Jordan has not previously been investigated using indirect haemagglutination (IHA) testing. In the present study, 512 blood samples were collected from recruited outpatients from an internal medicine clinic in Al-Mafraq Governmental Hospital in Jordan. Each participant signed a consent form and completed a questionnaire. The presence of antibodies specific for E. granulosus antigens was detected using an IHA test. Statistical analysis was performed by SPSS software using the Chi-square test. In all, 4.1% of the study participants were seropositive for E. granulosus IgG antibodies. There was a significant correlation between unexplained weight loss among seropositive patients (P = 0.018). Seropositivity was significantly higher in patients who slaughtered sheep inside their houses (P = 0.023). HD seroprevalence did not correlate with gender (P = 0.433), age (P = 0.880), residency status (P = 0.938), or educational level (P = 0.808). The vast majority (75.2%) of participants reported no prior knowledge about HD, and 99.8% were not aware about the etiology of the disease.

Expansion of a highly sensitive and specific ELISA test for diagnosis of hydatidosis using recombinant EgB8/2 protein

Objective(s):

Hydatidosis is a zoonotic infection and endemic in Iran. Due to the serological cross-reactivity (of sera) with other parasitic infection, diagnosis of hydatid cyst is considered to be problematic. In this regard, application of recombinant antigens improves serological diagnosis for human hydatidosis. Here, we present an ELISA test based on B8/2 recombinant antigen of Echinococcus granulosus with particular regard to its capability to diagnose human hydatidosis.

Materials and Methods:

The synthesized E. granulosus B8/2 (EgB8/2) gene was sub-cloned into pET28b (+) plasmid. Nde1 and Hind3 restriction enzymes were used to confirm the recombinant plasmid extraction. Cloning was verified by colony PCR, digestion enzymes, and sequence determination methods. To express rtEgB8/2, strains of Escherichia coli BL21 (DE3) pLysS and Rosetta (DE3) were induced with isopropyl β-D-1-thiogalactopyranoside (IPTG). A Ni-NTA column was used for purification, and the expressed protein was analyzed by SDS-PAGE as well as western blotting. ELISA test was used to identify the antigenicity of produced protein.

Results:

The presence of EgB8/2 gene fragment in the recombinant plasmid was confirmed. SDS-PAGE showed that the BL21 (DE3) pLysS strain had the highest level of expression and a protein band of 11 kDa was observed in induced bacteria. Western blotting approved the purity of rtEgB8/2 protein, and ELISA test measured sensitivity and specificity as 95% and 97.5%, respectively.

Conclusion:

E. granulosus metacestode contains a high amount of antigen B protein. These results confirm the reproducibility of high-quality rtEgB8/2 recombinant antigen as a reliable candidate in serological test.

Expression and purification of truncated recombinant B8/1 protein of Echinococcus granulosus for diagnosis of hydatid infection in human

Hydatidosis is one of the most important diseases common between animals and human beings. Caused by Echinococcus granulosus tapeworm, the disease has a global epidemic. The serological diagnostic tests that are now utilized to confirm the imaging approaches have some drawbacks such as low sensitivity and cross-reaction with the serum of the patients infected with other parasites. The application of recombinant and synthetic antigens has proven improvement in the functionality of serological diagnostic tests. The purpose of this study was to demonstrate the expression and purification of truncated recombinant B8/1 (trB8/1) antigen and its application in ELISA for diagnosis of hydatid infection in human. The tEgB8/1 was colonized in the expression vector pET28b (+) and expressed in different strains of E. coli. This protein was purified by Ni²⁺-NTA chromatography. The antigenicity of the protein was evaluated by Western blotting and ELISA. In the test, 50 positive serum samples from hydatid infected patients, 50 samples from healthy people, and 30 serum samples from patients with other parasitic diseases were used to determine the sensitivity and the specificity of this antigen. The measured sensitivity and specificity of this antigen were identified to be 75.75% and 96.38% respectively. The P value of <0.0001 by using ROC curve, confirmed that this antigen is able to differentiate between healthy and hydatid-infected individuals. Considering the excellent specificity of this antigen and in order to enhance the sensitivity, it is recommended to use a combination of this antigen with other antigens (e.g., EgB8/2-8/5).

Validation of a one-step PCR assay for the molecular identification of Echinococcus granulosus sensu stricto G1-G3 genotype

The Italian National Reference Center for Echinococcosis (CeNRE, Sassari, Italy) set up a diagnostic protocol of "one-step-PCR" useful for the detection of E. granulosus sensu stricto (E.g.s.s.) and the identification of its genotype (G1-G3). The purpose of this work was to perform the validation of the "PCR E.g.s.s." method. The procedures were performed employing the criteria of the World Organization for Animal Health as well as of the Italian Accreditation Body (ACCREDIA) based on the Regulation UNI CEI EN ISO/IEC 17025. Positive DNA samples belonging to E. granulosus, E. ortleppi, E. multilocularis, E. canadensis species were used for the experiments. Analytical specificity evidenced primer pairs Cal (Calreticulin l gene of 1001 bp) with an specificity higher respect to Ef1 (Elongation-Factor 1 Alpha gene of 706 bp) and NAD (Dehydrogenase-subunit 1 gene of 219 bp). The analytical sensitivity presented the capability to detect a very low amount of parasite DNA corresponding to a concentration of 12.5 pg/µl; accuracy and precision related to the operator performance, along with repeatability and reproducibility, evidenced high concordance among results and demonstrated an excellent κ values of Cohen. According to the good performance related to the evaluated parameters, the method "PCR E.g.s.s." was suitable for the validation procedure, and consequently, to be undergone to the accreditation process. In conclusion, the results demonstrated an elevated robustness and reliable features of the "PCR E.g.s.s." able to perform a rapid diagnosis of E. granulosus in only "one step", hence, it is likely to avoid the sequencing step.

Seroepidemiological study of cystic echinococcosis in nomadic communities in the southwest of Iran: A population-based study

The current study aimed at the seroepidemiological survey of human cystic echinococcosis (CE) in nomadic people in Boyer-Ahmad District in the southwest of Iran. One thousand and five nomads were selected by cross-sectional sample collection in nomadic tribes of Boyer-Ahmad District in the southwest of Iran. Blood samples were taken from each individual, and the sera were tested for detection of anti-hydatid cyst antibodies using antigen B-ELISA. A predesigned questionnaire which contained basic epidemiological and individual information related to hydatid cyst was filled for each subject during sample collecting. Subjects of the study were 227 males (22.6%) and 778 (77.4%) females. The mean age of the participants was 40.4 years old (±16.6). Anti-hydatid cyst antibodies were detected in 81 (8.1%) of the subjects. Seroprevalence rate for CE in females (9%) was more than males (4.8%). Multivariate logistic regression revealed significant associations between CE seropositivity and sex (odds ratio [OR] = 1.88; 95% confidence interval [CI] = 0.93-3.80) and dog ownership (OR = 8.3; 95% CI = 3.94-16.37). The rate of infection with CE in nomadic people in southwest of Iran is considerable. Treatment of dogs and increasing the level of people awareness may contribute a substantial advancement in the control of the disease in the area.

Genetic Variability of Antigen B8/1 among Echinococcus granulosus Isolates from Human, Cattle, and Sheep in Fars Province, Southern Iran

BACKGROUND

Cystic echinococcosis (CE), known as hydatid cyst, is a zoonotic parasitic infection caused by the larval stage of Echinococcus granulosus (E. granulosus). Antigen B, the major component of hydatid cyst fluid, is encoded by members of a multigene family. The present study aimed to evaluate the genetic diversity of the gene encoding antigen B8/1 (EgAgB8/1) among the main intermediate hosts of E. granulosus.

METHODS

Twenty-eight hydatid cyst isolates (10 sheep, 9 human, and 9 cattle) were collected in Fars province, Iran. DNA was extracted from each cyst and PCR, followed by DNA sequencing was used to identify potential EgAgB8/1 sequence variation and polymorphism. A phylogenetic tree was constructed using MEGA 7.0 software and the maximum likelihood method.

RESULTS

Using EgAgB8/1 primers, an approximately 315 bp band was amplified from all the isolates. The PCR products were sequenced, and the sequences were deposited in GenBank (accession numbers, KY709266-KY709293). The polymorphism variation among the isolates was 0.0, while intra-species variation within the isolates and related sequences in GenBank was 0.5-1%. Analysis of the phylogenetic tree revealed that the isolates from humans, sheep, and cattle all cluster in one group and are homologous to the EgAgB8/1 M1 allele.

CONCLUSION

Findings of this study revealed close similarity between the EgAgB8/1 of human, sheep, and cattle E. granulosus isolates. However, differences were found between the EgAgB8/1 sequences in our study and those reported from other CE endemic areas. Whether such similarities and differences exist in other subunits AgB subunits require further study.

DNA extraction from hydatid cyst protoscolices: Comparison of five different methods

Aim:

The current study aimed to find out a simple, practical and high throughput DNA isolation method for extraction of DNA from hydatid cyst samples.

Materials and Methods:

Cattle and sheep isolate of hydatid cysts were obtained from the slaughterhouse, and hydatid fluid and protoscolices were collected in a sterile condition. Protoscolices were washed, 3 times with phosphate buffered saline, and DNA was extracted by different methods including manual extraction with freeze/thawing and phenol-chloroform, Triton X-100 extraction, and by a commercial kit (YTA, Yekta Tajhiz Azma, Iran) with three different modifications in the kit’s manufacturer instructions. The obtained DNA from the different methods was evaluated by Nanodrop in terms of the yield of DNA and carbohydrates or protein contaminations. To compare the quality of the extracted DNA, two pieces of the mitochondrial genome of Echinococcus granulosus, cox1, and nad1, were polymerase chain reaction (PCR)-amplified, using each of the DNA prepared by different methods. Electrophoresis of PCR products was carried out on the agarose gel.

Results:

The DNA extracted by manual method, using phenol/chloroform, had the highest yield, yet with the highest level of protein and carbohydrate contamination. The DNA extracted using two-step incubations, initially at 60°C for 2 h and then overnight at 37°C, was the most purified DNA with the lowest rate of contamination.

Conclusion:

Findings of the study demonstrated that modification in the currently available commercially DNA extraction kit resulted in the development of a high throughput DNA isolation method. This method can be recommended for the extraction of DNA from hydatid cysts, especially the cattle isolate where the extraction of DNA in these samples are usually problematic.

Echinococcosis: Unexpected Occurrence and the Diagnostic Contribution of Routine Histopathology

Echinococcus is the smallest of the major tapeworms. Humans are incidental hosts who become infected by exposure to soil contaminated with ova from the feces of the canine definitive hosts. The major species are E. granulosus (cystic echinococcosis) and E. multilocularis (alveolar or sylvatic echinococcosis), both common worldwide but unusual and not reportable in the United States. Human disease is characterized by slowly growing visceral cystic masses often containing daughter cysts and hydatid sand. In nonendemic areas, the clinical evaluation includes imaging, serology, and surgery; metastatic tumor is a major consideration. The diagnosis depends on the morphologic recognition of scolices and hooklets, albeit degenerated, within the cyst or attached to the cyst wall. Highly suggestive cyst wall features are an acellular hyaline lining surrounded by focally calcific fibrous tissue and chronic inflammation. We report 7 patients encountered in the Chicago area (5 E. granulosus, 2 E. multilocularis) who presented with cystic masses affecting the liver, lung, soft tissue, and spleen. The initial diagnosis was established or suggested by intraoperative evaluation of cyst fluid or cyst wall histopathology. Organism parts were found in 5 cases; 1 patient had a hyalinized cyst wall with a positive IgG (enzyme-linked immunosorbent assay), and 1 had a positive Western blot and a 30-year history of treatment. Treatment included cyst resection, hepatic lobectomy, intraoperative cyst injection, and benzimidazole therapy. There was 1 death. In a nonendemic area, the awareness of the pathologist to the possibility of this disease will exclude a neoplasm and facilitate prompt antihelminthic treatment.