Dataset Information

Genotype Characteristics of Giardia duodenalis in Patients Using High Resolution Melting Analysis Technique in Khorramabad, Iran.

ABSTRACT:

Background

We aimed at genotyping and evaluating the predominance of G. duodenalis assemblages isolated from patients referred to medical laboratories in Khorramabad, Iran from Nov 2015 to Sep 2016. Hence, the development of a cost-effective HRM approach to determine genotypes of G. duodenalis based on the triosephosphate isomerase (tpi) gene was examined and the genotyping results with and without diarrhea was compared.

Methods

Seventy G. duodenalis positive fecal samples were collected. A microscopic confirmation for the presence of Giardia spp. was performed, cysts of 70 Giardia spp. positive specimens were concentrated using sucrose flotation technique and sucrose solution PCR amplification was performed on 69 of 70 (98.5%) samples, and High Resolution Melting (HRM) analysis was performed using a software.

Results

The results showed two distinct genotypes (assemblages A and B) of G. duodenalis but infections with mixture of both assemblages were not detected. The genotypes of G. duodenalis showed that the sub assemblage AI, BIII and BIV were present in a proportion of 68.1%, 20.3% and 11.6% respectively in samples. Assemblage AI was significantly (P<0.05) more frequently found in patients with diarrhea.

Conclusion

The sub-assemblage AI, BIII, and BIV are more zoonotic potential. According to the comparison of the results of this study with the results of previous studies in this area and around of it, as well as the way people live and keep pets. This pattern established in Khorramabad city. HRM can be an ideal technique to detect and genotyping of G. duodenalis in clinical samples.

SUBMITTER: Sepahvand A

PROVIDER: S-EPMC7311821 | biostudies-literature | 2020 Apr-Jun

REPOSITORIES: biostudies-literature

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Publications

Genotype Characteristics of <i>Giardia duodenalis</i> in Patients Using High Resolution Melting Analysis Technique in Khorramabad, Iran.

Sepahvand Akram A Hosseini-Safa Ahmad A Yousofi Hossein Ali HA Tajedini Mohammad Hassan MH Pahlavan Gharehbabah Reza R Pestehchian Nader N

Iranian journal of parasitology 20200401 2

<h4>Background</h4>We aimed at genotyping and evaluating the predominance of <i>G. duodenalis</i> assemblages isolated from patients referred to medical laboratories in Khorramabad, Iran from Nov 2015 to Sep 2016. Hence, the development of a cost-effective HRM approach to determine genotypes of <i>G. duodenalis</i> based on the triosephosphate isomerase (tpi) gene was examined and the genotyping results with and without diarrhea was compared.<h4>Methods</h4>Seventy <i>G. duodenalis</i> positive ...[more]

PMID: 32595710

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Project description:Giardia duodenalis is one of the main enteric pathogens associated with diarrheal disease. In developing countries, giardiasis is a major public health concern, particularly in children under five years of age. This study aimed to evaluate the occurrence and genetic diversity of G. duodenalis causing human infections in Shushtar County, Southwestern Iran. Individual faecal specimens were collected from 1,163 individuals (male/female ratio: 0.9; age range 2-75 years) with (n = 258) and without (n = 905) gastrointestinal symptoms living in rural and urban settings during the period 2017-2018. Conventional (sucrose flotation and microscopy) methods were used for the initial detection of G. duodenalis cysts in faecal specimens. Microscopy-positive samples were confirmed by PCR amplification and sequencing of the small subunit rRNA (ssu rRNA) gene of the parasite. A multilocus genotyping (MLG) scheme targeting the triose phosphate isomerase (tpi), the glutamate dehydrogenase (gdh), and the beta-giardin (bg) genes was used for genotyping purposes. Giardia duodenalis cysts were detected in 7.7% (90/1,163) of samples by microscopy, of which 82 were confirmed by ssu-PCR. Successful amplification and sequencing results were obtained for 23.2% (19/82), 9.8% (8/82), and 8.5% (7/82) of the confirmed samples at the tpi, gdh, and bg loci, respectively. MLG data for the three loci were available for two samples only. Out of the 24 samples genotyped at any loci, 50% (12/24) were identified as assemblage A and the remaining half as assemblage B. Overall, AII was the most prevalent sub-assemblage detected (41.7%, 10/24), followed by BIII (25.0%, 6/24), discordant BIII/BIV (5/24) or AII/AIII (2/24) sequences, and BIV (1/24). No significant correlation was demonstrated between a given assemblage/sub-assemblage and the occurrence of clinical symptoms. No genotypes adapted to animal hosts other than humans (e.g. assemblages C-F) were found circulating in the investigated human population, suggesting that transmission of human giardiasis in this Iranian region is primarily of anthroponotic nature. Further molecular-based studies are needed to confirm and expand these results, and to ascertain the presence and public health relevance of the parasite in environmental (e.g. drinking water) samples.

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