Molecular detection and genotype identification of Acanthamoeba species from bronchoalveolar lavage of patients with pulmonary symptoms suspected of cancer.

Abstract

Acanthamoeba spp. are the most common free-living amoeba worldwide, inducing life-threatening diseases such as Granulomatous Amoebic Encephalitis, pulmonary infection, and amoebic keratitis. This study aimed to identify the FLA and Acanthamoeba genotypes in patients with pulmonary symptoms suspected of cancer in Kashan's hospitals, Kashan, Iran. This cross-sectional study was conducted on 97 bronchoalveolar lavage samples of patients with respiratory symptoms suspected of lung cancer, who were admitted to the Shahid Beheshti Hospital of Kashan from 2019 to 2020. The samples were cultured onto 1.5% non-nutrient agar enriched with killed Escherichia coli and examined for the presence of FLA. Following amoeba isolation and DNA extraction, Acanthamoeba spp. were determined by Polymerase Chain Reaction using JDP1 and JDP2 primers, which amplified a 490bp fragment from the 18 S rDNA gene. Eighteen Acanthamoeba isolates were sequenced, and the genotypes were identified. The prevalence of FLA and Acanthamoeba and the relationship between symptoms and demographic variables were analyzed with SPSS Software version 16. The prevalence rates of FLA and Acanthamoeba in the BAL samples was 86.6% and 73.2%, respectively. All Acanthamoeba isolates belonged to the T4 genotype. The most symptoms among Acanthamoeba-positive patients were dyspnea and cough; however, their difference was not statistically significant. The findings indicated the high prevalence of FLA and Acanthamoeba in BAL in the population suspected of cancer in Kashan. Since the T4 genotype is a pathogenic genotype of Acanthamoeba, training health and improving sanitation levels would help to prevent infection.