Cystic Echinococcosis in Pakistan: A Review of Reported Cases, Diagnosis, and Management

Total Cystectomy in the Management of Primary Retroperitoneal Echinococcal Cysts: Current Evidence and Future Directions

Echinococcal cysts (ECs) are a significant public health concern globally, particularly in endemic regions. Among these, primary retroperitoneal echinococcal cysts (PRECs) present unique challenges due to their location and complex presentations. Total cystectomy, involving complete removal of the EC and surrounding tissue, is a surgical option for managing PRECs. However, evidence regarding its efficacy and safety is limited. We conducted a systematic review following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines to evaluate the role of total cystectomy in managing PRECs. A comprehensive search of databases yielded four relevant studies. These studies reported favorable outcomes following total cystectomy, including low recurrence rates and minimal postoperative complications. However, challenges such as technical complexity and proximity to vital structures were noted. Future research should focus on evaluating minimally invasive approaches, exploring adjuvant therapies, identifying predictors of recurrence, and assessing cost-effectiveness. This systematic review underscores the need for further investigation to optimize the management of PRECs and improve patient outcomes.

Past and Present of Diagnosis of Echinococcosis: A Review (1999-2021)

The larval forms of taeniid cestodes belonging to the genus Echinococcus are the source of the zoonotic infection known as echinococcosis. Alveolar and cystic echinococcosis are caused by Echinococcus multilocularis and Echinococcus granulosus (s. s) respectively. It is endemic in several regions of the world. In this systematic review, we describe diagnosis, and the species (human, canids, livestock, and small rodents) affected by cystic (CE) and alveolar echinococcosis (AE). From 1999 to 2021, we searched the online directory through PubMed, SCOPUS, Web of Science, and google scholar. Among the 37,700 records found in the online databases, 187 publications met our eligibility requirements. The majority of investigations employed a range of diagnostic methods, such as ELISA, imaging, copro-PCR, necropsy or arecoline hydrobromide purgation, morphological cestode confirmation, and fecal sieving/flotation to detect and confirm Echinococcus infection. ELISA was the most commonly used method followed by PCR, and imaging. The research team retrieved data describing the incidence or assessment of the diagnostic test for E. multilocularis in humans (N = 99), canids (N = 63), small ruminants (N = 13), large ruminants (N= 3), camel (N= 2), pigs (N=2) and small mammals (N= 5). This study was conducted to explore the diagnostic tools applied to detect echinococcosis in humans as well as animals in prevalent countries, and to report the characteristic of new diagnostic tests for disease surveillance. This systematic review revealed that ELISA (alone or in combination) was the most common method used for disease diagnosis and diagnostic efficacy and prevalence rate increased when recombinant antigens were used. It is highly recommended to use combination protcols such as serological with molecular and imaging technique to diagnose disease. Our study identified scarcity of data of reporting echinococcosis in humans/ animals in low-income or developing countries particularly central Asian countries. Study reports in small rodents indicate their role in disease dissemination but real situation in these host is not refected due to limited number of studies. Even though echinococcosis affects both public health and the domestic animal sector, therefore, it is important to devise new and strengthe implementation of the existing monitoring, judging, and control measures in this estimate.

An Epidemiological Survey to Investigate the Prevalence of Cystic Echinococcosis in Slaughtered Bovine Hosts in Punjab, Pakistan

Cystic echinococcosis (CE) is a neglected zoonotic disease of worldwide geographical distribution. CE is most common in underdeveloped and herding communities where people survive on animal husbandry and agricultural activities. The prevalence of CE in livestock and its risk factors are widely underreported, because of inefficient surveillance systems. The aim of this study was to evaluate the epidemiological characteristics and prevalence of CE in cattle in Punjab, Pakistan. Data were collected from slaughterhouses from September 2021 to February 2022. Ante- and postmortem examination and cyst characterization were performed. Epidemiological, demographic, and one health data were collected. A total of 8877 animals (8096 buffalo, 781 cattle) were examined, and the prevalence of CE was 6.22% (n = 552) in all animals, with a higher prevalence in cattle (15.20% vs. buffalo 5.83%). Prevalence was not significantly different in males and females. Of the 23 districts studied, the highest prevalence was in the Haripur district of KP (20.85%). The majority of animals studied were older than 3 years. Most cysts were found in animals older than 5 years. Lungs and liver were the predominant sites for the presence of cysts (65.58% and 31.34%, respectively. Of the collected cysts, 29.71% were fertile. The findings may be useful in estimating the eco-epidemiology of CE and improving surveillance and prevention programs in Pakistan.

A Retrospective Cohort Study on Human Cystic Echinococcosis in Khyber Pakhtunkhwa Province (Pakistan) Based on 16 Years of Hospital Discharge Records

Human cystic echinococcosis (CE) is a worldwide-distributed parasitic zoonotic disease, which represents a threat for both human and animals. The current study aimed at estimating the prevalence of human CE in Khyber Pakhtunkhwa (KPK) province of Pakistan. Clinical records from four major hospitals in this region were reviewed for CE human cases during the period of 2006–2021. Out of 251 (0.00071%) CE patients identified during the considered period, 142 (56.6%) were females, and 109 (43.4%) were males. The highest number of CE cases was recorded in the 21–30 (27.9%) age group, followed by 31–40 (23.1%) and 41–50 (16.3%). Most of the CE patients in KPK province were members of the Afghani ethnic group (17.1%); secondarily, they were Pakistani (6.4%), while for 76.5% ethnicity data were not available. The liver (41%) and the lungs (4.8%) were the most infected organs identified among CE patients in KPK province. The present study identified CE as a significant public health problem in KPK province, and the current findings demonstrated a constant endemicity of CE during the last 15 years. Further filed studies on the active search of CE carriers by means of ultrasound population-based surveys are needed to fill knowledge gaps on clinical and molecular epidemiology of human CE in Pakistan.

An Adrift and Homeless Cyst within the Peritoneal Cavity

Introduction

Echinococcosis is a zoonotic infection caused by Echinococcus species. Iran is endemic for Echinococcus granulosus. Here, we present a case of hydatidosis in an 85-year-old man, presented with acute, dull, constant, and generalized abdominal pain. A computed tomography scan (CT scan) showed an intact hydatid cyst on the bladder dome and several hydatid cysts in the liver. Open surgery revealed a cyst with hepatic origin, confirmed with histopathological studies.

Conclusion

Although a primary abdominal hydatid cyst is very rare, it can be transferred to the abdominal cavity without any rupture as secondary ones. In this case, rupture of the liver wall was the reason for this transfer. As a result, there should be a suspicion of hydatidosis in a patient with a similar presentation.

Detection of Anti-Echinococcus granulosus Antibodies in Humans: An Update from Pakistan

Human cystic echinococcosis (CE) is a zoonotic disease caused by the larval stage of Echinococcus granulosus sensu lato that causes economic losses by affecting livestock and also poses a public health threat worldwide. The present study is the first retrospective report on the seroprevalence of anti-E. granulosus antibodies in humans in Pakistan. The study used data from 93 blood analysis reports of patients suspected of having CE from different medical centers in Lahore, Pakistan. Out of 93 sera samples, 20 (21.5%) were seropositive, and higher seropositivity (17.2%) was recorded with the indirect hemagglutination test (IHA) than with enzyme-linked immunosorbent assay (ELISA). The findings indicated that age, gender, and year had no significant relationship with the seropositivity of CE. The current study provides directions towards the management of the disease in the near future in Pakistan.

Molecular characterization and phylogenetic studies of Echinococcus granulosus and Taenia multiceps coenurus cysts in slaughtered sheep in Saudi Arabia

Taeniids, consisting of two genera Echinococcus and Taenia, are obligatory tapeworms of mammals, and their pathogenicity was due to infection with larval stages. Hydatid (the larval stage of Echinococcus granulosus) and coenurus (the larval stage of Taenia multiceps) cysts are prevalent in domestic, wild ruminants, livestock, swine, and dogs, and accidentally they could also be found in humans. They lead to different clinical manifestations that cause economic loss in livestock and human morbidity. In Saudi Arabia, few studies were performed on hydatid and coenurus cyst genetic variations. The main goal of the present study was to identify E. granulosus and T. multiceps cyst isolates collected from slaughtered Harri sheep in Saudi Arabia by partial sequencing with PCR amplification of the cytochrome C oxidase 1 (COX1) gene. Molecular and phylogenetic evaluation based on COX1 sequences indicated that cyst isolates belong to E. granulosus and T. multiceps, respectively, successfully submitted in NCBI Genbank. Molecular characterization showed a low nucleotide diversity with two submitted isolates of coenurus with related isolates of Genbank. Conversely, E. granulosus isolates showed higher nucleotide diversity. The reported data could serve as a foundation for future molecular epidemiological and biological studies.

Estimation of the monetary burden of treated human cystic echinococcosis in Pakistan

Cystic echinococcosis (CE), caused by the larval stage of Echinococcus granulosus sensu lato tapeworms, continues to be a public health problem in many endemic countries, including Pakistan. Patient level data, including age, sex, and cyst(s) location for surgically managed CE patients for the years 2013-2016 from hospitals located in Punjab and Khyber Pakhtunkhwa provinces were obtained from medical charts. Direct and indirect costs associated with surgically managed CE patients treated in private and public hospitals were then estimated and applied to country-level case numbers estimated through the Global Burden of Disease Study. A total cost of US$4,068,666 (95% CI: US$3,097,684 - US$5,295,702) was estimated for the year 2017, with US$3,951,853 (95% CI: US$2,981,400 - US$5,177,610) attributable to direct diagnosis and treatment-related costs and US$117,137 (95% CI: US$91,841 - US$146, 979) attributable to wage losses during the treatment period. Mean direct cost per patient (US$1,056) was approximately 72% of the country's per capita gross domestic product (GDP). Surgical management continues to be the treatment of choice for CE patients in Pakistan. If physicians were to adhere to World Health Organization Informal Working Group on Echinococcosis (WHO-IWGE) cyst stage-specific treatment guidelines, it is likely that the number of surgical interventions would decrease as would treatment costs.

Albendazole Nanocrystal-Based Dissolving Microneedles with Improved Pharmacokinetic Performance for Enhanced Treatment of Cystic Echinococcosis

Cystic echinococcosis (CE) is a zoonosis caused by Echinococcus spp., affecting both humans and animals' lives. Current treatment of CE by oral administration of albendazole (ABZ) is hampered by several limitations. The poor aqueous solubility and the rapid metabolism of ABZ in the liver are the main issues, leading to lack of efficacy of the treatment. In the present study, we developed a nanocrystalline (NC) formulation of ABZ to be delivered intradermally using dissolving microneedles (DMNs). The NC formulation was developed using milling in an ultrasmall-scale device. Following several screenings, Pluronic F127 was selected as a suitable stabilizer, producing NCs with around 400 nm in size with narrow particle distribution. The crystallinity of ABZ was maintained as observed by DSC and XRD analysis. The NC approach was able to improve the dissolution percentage of ABZ by approximately three-fold. Furthermore, the incorporation of NCs into DMNs using the combination of poly(vinylpyrrolidone) and poly(vinyl alcohol) formed sharp needles with sufficient mechanical strength and insertion properties. Dermatokinetic studies revealed that >25% of ABZ was localized in the dermis of excised neonatal porcine skin up to 48 h after DMN administration. In in vivo pharmacokinetic studies, the AUC and relative bioavailability values of ABZ delivered by NC-loaded DMNs were found to be significantly higher than those obtained after oral administration of coarse suspension of ABZ or ABZ-NCs, as well as DMNs delivering coarse ABZ as indicated by the relative bioavailability values of >100%. Therefore, the combination approach developed in this study could maintain the systemic circulation of ABZ, which could be possibly caused by avoiding the first-pass metabolism in the liver. This could be beneficial to improve the efficacy of ABZ in CE treatment.

Haplotype comparisons of Echinococcus granulosus sensu lato via mitochondrial gene sequences (co1, cytb, nadh1) among Pakistan and its neighbouring countries

Echinococcus granulosus sensu lato (s.l.) is a zoonotic parasite that causes cystic echinococcosis (CE) in humans. However, E. granulosus sensu stricto (s.s.) is considered the predominant species in CE infections worldwide. According to the population genetic diversity and structure of E. granulosus s.l., gene flow can explain the parasite drift among the neighbouring countries of Pakistan. The mitochondrial (mt) co1 (n = 47), nadh1 (n = 37) and cytb (n = 35) nucleotide sequences of E. granulosus s.l. isolates from Pakistan, Iran, China and India were retrieved from the National Centre for Biotechnology Information database to determine the genealogical relationships. The sequences were grouped as the mt-co1 (genotypes G1 and G3, G6-G7), mt-cytb (genotypes G1 and G3), and mt-nadh1(genotypes G1 and G3). The data were analysed using bioinformatic tools. A total of 19 polymorphic sites for the mt-co1 sequence (374 bp) were observed of which 31.6% (6/19) were parsimony-informative sites. Unique singleton haplotypes within the E. granulosus s.s. haplotype network based on the mt-co1 gene were highly prevalent (68.4%; 13/19) in Pakistani isolates followed by Chinese, Indian and Iranian isolates; four polymorphic sites were detected in the E. canadensis (G6/G7). In E. canadensis mt-co1 haplotype network, 75% (3/4) unique singleton haplotypes were from the Iranian isolates. Twelve polymorphic sites were found using the mt-cytb sequence (547 bp); 25% (3/12) were parsimony-informative and there were 66.7% (8/12) unique singleton haplotypes within the mt-cytb haplotype network in E. granulosus s.s. with the most reported from Pakistan followed by Iran and China. 20 polymorphic sites were detected in E. granulosus s.s. mt-nadh1 sequences (743 bp); 20% (4/20) were parsimony-informative. There were 66.7% (8/12) main single haplotypes within the mt-nadh1 haplotype network, with the most reported from Pakistan followed by that from India, Iran and China. The sequence analyses show low nucleotide diversity and high haplotype diversity in general.

Factors Affecting the Choice of Treatment in Hepatic Hydatid Cyst Surgery

OBJECTIVE

We aimed to determine the effective factors in the selection of treatment methods for patients with hepatic hydatid cyst undergoing surgery and the variables effective when performing postoperative endoscopic retrograde cholangiopancreatography (ERCP). In addition, we aimed to reveal the factors affecting the recurrence, postoperative complications, and length of stay of these patients.

MATERIALS AND METHODS

A total of 107 patients diagnosed with hepatic hydatid cysts were treated surgically. Data were obtained from the records of these patients. Chi-square test was used for the analysis. The variables that were found to be significant in the chi-square analysis were included in the logistic regression (Backward: LR) analysis.

RESULTS

Of all patients, 6.5% underwent the puncture, aspiration, injection, and reaspiration (PAIR) technique, 67.3% underwent conservative surgery, and 26.2% underwent radical surgical treatment. In paired comparisons, a significant difference was found among the ultrasonographic size of the cyst (p = 0.033), the radiological classification of the cyst (0.006), and history of previous surgery and treatment methods for the cyst. The risk of performing ERCP was 25.710 [95% confidence interval (CI): 1.721-284.013] folds higher for cysts located in the left lobe, whereas it was 19.992 (95% CI: 2.004-199.488) folds higher for cysts located in both right and left lobes. When the radical surgical treatment method was taken as a reference, the status of ERCP implementation was 29.785 (95% CI: 1.844-480.996) folds higher for PAIR and 3.628 (95% CI: 0.355-37.103) folds higher for conservative surgery.

CONCLUSION

In conclusion, radical surgery is a significant treatment for hepatic hydatid cyst as its ultrasonographic cyst size increases with time. The location and treatment method of the cyst increases the complication of biliary fistula and requires ERCP.

Echinococcoses in Iran, Turkey, and Pakistan: Old Diseases in the New Millennium

Echinococcosis is considered a cosmopolitan zoonosis caused by different species of small taeniid tapeworms of the genus Echinococcus and is regarded as a neglected zoonosis. Cystic and alveolar echinococcoses are endemic diseases of Tibetan, Pamir, and Iranian plateaus. All of the countries within the Iranian plateau are affected by echinococcosis. Pakistan, Turkey, and Iran are the three most populous countries of the region, in which echinococcosis is highly endemic. The three neighboring countries share strong cultural and socioeconomic ties. The present study aimed to provide a broad review of the status of cystic and alveolar echinococcosis, summarizing the current knowledge about geographical distribution, molecular epidemiology, and transmission dynamics of Echinococcus granulosus sensu lato and Echinococcus multilocularis in this region. Additionally, we aimed to understand disease burden and risk factors as basic requirements for establishing a surveillance system and planning prevention and control programs. A considerable body of information is available on different aspects of echinococcosis in this region; however, several information and research gaps need to be filled before planning control programs. None of the countries in the region have an elaborate echinococcosis control program. Effective control programs require multi/intersectoral coordination within a One Health approach with a long-term political and administrative commitment and enhanced international collaboration among the three countries.

Demographics of Cystic Echinococcosis Patients Treated Surgically in Lahore, Pakistan: A Single Centre Study from 2007 - 2018

Cystic echinococcosis (CE) is a zoonotic disease caused by the larval stage of Echinococcus granulosus tapeworms. These parasites have a worldwide geographic distribution and pose a serious threat to livestock industry as well as human health in the endemic areas. CE is widely distributed in Pakistan. However, very few reports are available related to the regional transmission of E. granulosus. A retrospective analysis was conducted of surgically confirmed CE patients who were treated at Shoukat Khanum Memorial Cancer Hospital and Research Centre in Lahore, Punjab Province, Pakistan from 2007 – 2018. In total, 536 CE patients were evaluated during the study period. Cases originated from the provinces of Khyber Pakhtunkhwa (n=336), Punjab (n=147), Baluchistan (n=18), Sindh (n=3), Islamabad (n=2), Gilgit Baltistan (n=1), and Azad Jammu and Kashmir (n=1). An additional 28 cases were from Afghanistan. The highest number of CE cases was reported in 2013 (n=90). Females made up a larger proportion of cases (n=310; 57.8 %) than males (n=226; 42.2 %). Most patients were members of the Pashtun (n=197; 36.7 %), Hindku (n=142; 26.5 %), and Punjabi (n=118; 22.0 %) ethnic groups. The largest number of cysts was obtained from the liver (137/536; 25.6 %). This study showed that CE is likely present throughout Pakistan. In order to control the disease, a comprehensive control program and regional surveillance are needed.