Genotyping of the Echinococcus granulosus in Paraffin-Embedded Human Tissue Samples from Iran

Molecular diagnosis of echinococcosis in patients based on frozen paraffin tissue samples and fixed formalin and hydatid cysts isolated from livestock in a slaughterhouse

Background

Various genotypes of Echinococcus granulosus have been studied in high-disease-risk areas and identified as causative agents of cystic echinococcosis (CE). This study was performed to examine and identify the molecular hydatid cyst in the dissected human specimens in paraffin tissue, and the dissected animal cyst was characterized using the DNA polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) of internal transcribed spacer 1 (ITS1).

Materials and Methods

To determine the molecular properties of E. granulosus, 20 hydatid cyst samples (including 6 sheep samples, 9 camel samples, and 10 human paraffin samples) were collected from Zahedan and Zabol cities. After DNA extraction, molecular PCR was performed, and RFLP was evaluated. In this study, the Taq1 endonuclease cleavage enzyme was used.

Results

The patterns of DNA bands found in the isolates from human CE and animal bladder cysts were the same, as indicated by the results of ribosomal DNA-ITS1 amplification from E. granulosus. Two nested primer pairs were used. The rough size of the enhanced ITS1 piece was 444 and 391 base pairs (bp), individually. After cutting the PCR product with the Taq1 enzyme, the patterns of the fragments revealed that the samples had two identical RFLP patterns. The aftereffects of this study showed that the parasite genotypes confined to sheep, camels, and people had hereditary changes.

Conclusion

The transcendent type of E. granulosus sensu lato in the area is E. granulosus sensu stricto, which featured the meaning of the sheep/canine cycle in human transmission. Albeit the band profile in the camel is now and again like the sheep strain, RLFP can be recognized utilizing the PCR strategy, and two differentiating band profiles using the chemical were found in this review.

Genotyping of Echinococcus granulosus isolated from canine in Northwest Iran

Echinococcus granulosus is a parasitic tapeworm that causes cystic echinococcosis, a potentially life-threatening zoonotic infection affecting humans and animals across the globe. In Iran, the prevalence of this parasite remains a significant public health concern, particularly in the northwest region. This study aimed to investigate the genotypes of E. granulosus isolated from canines in the northwest of Iran. A total of 87 samples were collected from the Mughan plain area in Ardabil province, including 47 stray dogs (Canis familiaris), 25 golden jackals (Canis aureus), and 15 red foxes (Vulpes vulpes), and molecular analysis was performed for partial cytochrome c oxidase subunit 1 and nad1 genes. Phylogenetic analyses were carried out on the obtained sequence. The findings revealed that 9 out of 87 (10.3%) samples were infected with Echinococcus parasites, with a frequency of 1 (4%) and 8 (17%) among golden jackals and stray dogs, respectively. Overall, all (100%) E. granulosus adult samples were related to the G1 genotypes. This study provides comprehensive data regarding the epidemiological and molecular characteristics of echinococcosis in canines in northwest Iran.

Echinococcus granulosus sensu lato Genotypes in Different Hosts Worldwide: A Systematic Review

INTRODUCTION

The aim of this study was to develop a synthesis of the evidence available regarding verified E. granulosus sensu lato (s.l.) genotypes in different species worldwide.

MATERIAL AND METHODS

A systematic review was performed including studies concerning genotypes of E. granulosus s.l. without language or genotyped method restriction, published between 1990 and 2020. A systematic search was carried out in Trip Database, BIREME, SciELO, LILACS, IBECS, PAHO-WHO, EMBASE, PubMed, Scopus, and WoS. Variables of interest were year of publication, country, number of samples, and hosts; genotypes, molecular marker, haplotypes and molecular biology techniques used. Descriptive statistics were applied.

RESULTS

2411 articles were analyzed, however 135 met the selection criteria, representing 8643 liver and lung samples. Of the samples selected 24% were human, the remaining samples pertained to non-human animal hosts; cattle and sheep prevailed with 28.6% and 26.6% of the studied samples, respectively. The reported evidence is mainly from Iran, Turkey, Argentina, China and Chile; with 50, 11, 6, 6 and 5 studies, respectively, published between 1992 and 2020 [most frequently during 2015-2020 (76/135 studies; 56.3%)]. The mitochondrial gene cox1 was generally sequenced and informative (91.8%). Genotypes most frequently identified were E. granulosus sensu stricto (s.s.) (83.2%).

CONCLUSIONS

Based on this overall evidence, it can be concluded that publications related to genotypes of E. granulosus s.l. are heterogeneous. E. granulosus ss accounts for the vast majority of the global burden of E. granulosus s.l. worldwide. Further studies including larger number of cases and adequate internal validity are required to specify the distribution of genotypes in various host species.

TRIAL REGISTRATION

PROSPERO CRD42018099827.