Molecular Identification, Subtypes Distribution, and Alleles  Discrimination of Blastocystis sp., Isolated from  Immunocompromised Subjects in Iran

Hanieh  Mohammad Rahimi; Seyed Ahmad  Karamati; Sara  Nemati; Hamed  Mirjalali; Mohammad Reza Zali

doi:10.18502/ijpa.v17i2.9534

Hanieh Mohammad Rahimi Foodborne and Waterborne Diseases Research Center, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran
Seyed Ahmad Karamati Department of Medical Parasitology and Mycology, Faculty of Medicine, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran
Sara Nemati Foodborne and Waterborne Diseases Research Center, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran
Hamed Mirjalali Foodborne and Waterborne Diseases Research Center, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran
Mohammad Reza Zali Gastroenterology and Liver Diseases Research Center, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran

DOI: https://doi.org/10.18502/ijpa.v17i2.9534

Keywords: Blastocystis sp.; Immunodeficiency; Opportunistic infection; Subtypes; Allele discrimination; Iran

Abstract

Background: Blastocystis sp., is a prevalent protist isolated from humans and animals, which its opportunistic role in immunocompromised patients is still controversial. The current study aimed to evaluate the subtype and alleles distribution of Blastocystis sp., among immunocompromised patients.

Methods: Totally, 33 microscopically Blastocystis-positive stool samples, isolated from Guilan province during April 2018 to May 2019 were investigated. Total DNA extraction was performed and the barcoding region of the small subunit ribosomal RNA (SSU rRNA) gene was amplified. Targeted fragments were sequenced to characterize subtypes and relevant alleles. Phylogenetic tree was constructed using Maximum-likelihood and Tamura 3-parameter to illustrate the correlation between subtypes and certain immunodeficiency.

Results: Subtype analysis revealed the presence of ST1, ST2, ST3, and ST7 among 13/33 (39.4%), 5 (15.2%), 14/33 (42.4%), and 1/33 (3%), of samples, respectively. ST1 was the major subtype among cancer patients 5/7 (71.42%), while ST3 was the predominant subtype among rheumatoid arthritis (RA) patients 3/6 (50%), internal ward patients 5/10 (50%), and asthma and allergy patients 2/3 (66.66%). ST7 was isolated from a patient hospitalized in internal ward. No significant correlation was seen between the type of immunodeficiency and subtypes (P-value = 0.771). The phylogenetic tree showed no separation regarding the type of immunodeficiency.

Conclusion: Among studied immunocompromised patients, ST3 was the most prevalent subtype followed by ST1. There was no specific correlation between subtypes and alleles with type of immunodeficiency. Putative zoonotic alleles were highlighted the probability of zoonotic transmission for Blastocystis sp.