Use of multiplex PCR in the differential detection of Entamoeba histolytica and/or Entamoeba dispar in comparison to microscopic examination

ABSTRACT

Intestinal amoebiasis, caused by E. histolytica, is a major public health problem in developing countries. E. dispar is morphologically identical to E. histolytica, but is considered a commensal protozoan. Differential identification of E. histolytica and/or E. dispar is important for treatment and epidemiological studies of intestinal amoebiasis. To evaluate multiplex PCR in the differential detection of E. histolytica and/or E. dispar in comparison to conventional microscopic stool examination. The present study was performed on 100 individuals. They were divided into symptomatic and asymptomatic groups according to the presence or absence of symptoms and signs of intestinal amoebiasis. Stool samples were collected and subjected to microscopic examination of fresh preparations of direct wet mount and formalin diethyl ether concentrates, and of permanent preparations stained by trichrome, in addition to molecular assay using multiplex PCR. Percentage detection of Entamoeba species was highest by multiplex PCR [36%] and lowest by direct wet mount [25%]. Multiplex PCR detected E. histolytica in 25%, E. dispar in 41.7% and mixed infection in 33.3% of cases. The sensitivity of PCR was 96.4% compared with the trichrome stain [75%]. Multiplex PCR was more sensitive than the conventional microscopic techniques in the differential detection of E. histolytica and/or E. dispar, at the same time and in a single PCR round