A nested, multiplex, PCR assay for the simultaneous detection and differentiation of Entamoeba histolytica and Entamoeba dispar in faeces

The detection of and differentiation between Entamoeba histolytica and Enta moeba dispar are of great importance, both for diagnosis and for epidemiolo gical studies. Most PCR-based methods for the discrimination of these two s pecies employ complex procedures for DNA extraction and require different p rotocols for E. histolytica and E. dispar, leading to relatively high expen diture, labour costs and turnaround times. A simple, rapid, cost-effective and yet sensitive and specific multiplex PCR technique has now been develop ed for the simultaneous detection and differentiation of E. histolytica and dispar in faecal samples. The detection limit is 200 trophozoites of B. di spar or 1000 trophozoites of E. histolytica/g stool sample. The sensitivity of the assay remains practically unchanged, even in the presence of 20 000 trophozoites of the other species/g stool sample. Thus, this technique may also easily reveal mixed infections, without the danger of misdiagnosis ca used by one strain displacing the other in culture.