Differentiation of Entamoeba histolytica from Entamoeba dispar by nested multiplex polymerase chain reaction

Abstract

Background: Amoebiasis is a parasitic disease caused by the intestinal protozoon Entamoeba histolytica. Microscopic examination fails to differentiate E. histolytica from the morphologically identical nonpathogenic Entamoeba dispar. To avoid unnecessary treatment of individuals infected with nonpathogenic E. dispar, it is essential to differentially diagnose infections caused by pathogenic from nonpathogenic Entamoeba spp. Objective: The aim of this study was to assess the efficacy of nested multiplex PCR (NM PCR) technique as a diagnostic method for differentiating infections caused by E. histolytica and E. dispar. Materials and methods: Stool samples collected from patients with and without symptoms of amoebiasis were screened for E. histolytica/E. dispar trophozoites/cysts by microscopic examination. NM PCR was performed on a total of 52 samples targeting the genus-specific 16S-like ribosomal RNA gene for simultaneous, differential detection of E. histolytica and E. dispar. Results: NM PCR detected E. histolytica at 439 bp and E. dispar at 174 bp, and it was positive in 31 out of 32 cases with a sensitivity of 96.85%. From those, 17 (32.7%) samples were positive for E. histolytica, 12 (23.1%) for E. dispar, and three (5.7%) for both species. In addition, NM PCR diagnosed E. dispar in one of the negative controls with a specificity of 95%. Conclusions: NM PCR is useful for the specific detection of E. histolytica and E. dispar in stool samples. Additional methods for species differentiation have been used to avoid unnecessary treatment of individuals infected with the nonpathogenic species [12]. PCR demonstrated excellent sensitivity and specificity

The epidemiology of amoebiasis in Thi-Qar Province, Iraq (2015-2020): differentiation of Entamoeba histolytica and Entamoeba dispar using nested and real-time polymerase chain reaction

“…Of these samples, 25 and 14 were positive for E. histolytica and E. dispar with nested PCR, respectively, whereas 28 and 15 were found to be positive using real-time PCR. This result aligns with those of other studies, such as those conducted by Mohammed et al [ 30 ], Al-Saqur et al [ 28 ], and Faqe Mahmood & Mustafa [ 18 ]. However, the low results for molecular identification may be due to the lysis of trophozoites resulting from sample storage or due to the presence of other Entamoeba spp.…”