Differentiation of Entamoeba histolytica, Entamoeba dispar and Entamoeba moshkovskii from diarrhoeic stools using Polymerase Chain Reaction in Kaduna, Nigeria

Abstract

Background: Entamoeba species have been reported to cause a high morbidity and mortality rate.

Aim: The study was aimed at detecting and differentiating E. histolytica, E. dispar and E. moshkovskii using molecular technique (PCR).

Methods: Microscopic examination of the faecal samples was carried out by the Formol-Ether concentration technique. DNA was extracted from microscopic positive stool samples and used to amplify a part of the genus Entamoeba small-subunit ribosomal RNA gene (SSU rDNA), using the Nested Multiplex Polymerase Chain Reaction (NM-PCR).

Results: Of the 528 faecal samples, 46 (8.7%) were positive for Entamoeba by microscopy. The PCR results showed that out of the 46 microscopy positive samples, 16 (34.8%) successfully generated species-specific amplicons of Entamoeba species DNA. The infection with E. dispar (68.8%; 11/46) was the most common, followed by E. histolytica (37.5%; 6/46) and E. moshkovskii (18.8%; 3/46). Of these, 7 (43.8%) were shown to contain only E. dispar, 3 (18.8%) contained only E. histolytica and 2 (12.5%) contained only E. moshkovskii. Mixed infection with E. histolytica and E. dispar was found in 3 (18.8%) and E. dispar and E. moshkovskii in 1 (6.3%) sample.

Conclusion: This study therefore highlighted the great importance of the use of molecular techniques to differentiate between E. histolytica, E. dispar and E. moshkovskii because it obviates unnecessary chemotherapy with possible costs, side effects and drug resistance. The use of PCR in the diagnosis of amoebiasis and epidemiological survey in Nigeria is thus recommended.

Keywords: Entamoeba histolytica, Entamoeba dispar, Entamoeba moshkovskii, DNA, Polymerase Chain Reaction, amoebiasis