Entamoeba moshkovskii and Entamoeba dispar-associated infections in pondicherry, India.

The prevalence of Laredo strain--Entamoeba moshkovskii--and non-pathogenic E. dispar in patients attending the Jawaharlal Institute of Postgraduate Medical Education and Research hospital, Pondicherry, India, is reported here. E. moshkovskii is reported for the first time in India. The species are morphologically indistinguishable from pathogenic E. histolytica. Of 746 stool samples screened, 68 showing cyst or trophozoite stage of E. histolytica, E. dispar, or E. moshkovskii were subjected to small subunit (SSU) rRNA gene-based polymerase chain reaction, which revealed a higher prevalence of E. dispar (8.8%) and E. moshkovskii (2.2%) compared to E. histolytica (1.7%) in patients. Only 19% of the 68 stool samples, resembling E. histolytica by microscopy, were actually E. histolytica, implying that 81% of suspected infections were misdiagnosed and would have been treated unnecessarily with anti-amoebic drugs.