High prevalence of Entamoeba moshkovskii infection in HIV seropositive patients of Barak Valley, Assam, India

Background

It is now well established that Entamoeba moshkovskii and Entamoeba dispar are two distinct non-pathogenic species, microscopically indistinguishable from pathogenic Entamoeba histolytica. Being endemic, there are no data on the prevalence of these commensal infections from the North Eastern part of India.

Methods

A total of 274 stool samples collected in this cross sectional study from HIV seropositive patients attending the ART centre of SMCH, Assam, India were screened for cyst and/ trophozoite stage of Entamoeba using iodine staining technique and then subjected to SSU rRNA gene based multiplex PCR assay.

Results

Out of 274 stool samples, multiplex PCR assay of 61 microscopy positive samples showing cyst and/ trophozoite stage of Entamoeba, revealed a higher prevalence of E. moshkovskii (12.8%; 95% CI= 9.30, 17.28) and lower prevalence of E. dispar (6.2%; 95% CI=3.85, 9.77) compared to E. histolytica (8.1%; 95% CI= 5.31, 11.91; p< 0.05). Of the 61 samples that were microscopically positive, 5 were E. histolytica, 8 were E. dispar, 25 were E. moshkovskii, 17 were mixed infections with E. histolytica and 6 were PCR negative which may be non-histolytica/dispar/moshkovskii infection. Thus, only 36% of the 61 microscopy positive stool samples were actually E. histolytica, implying that remaining 64% of so called infections were over represented and would have been treated unnecessarily.

Conclusion

This is the first report of E. moshkovskii infection from this region of India and its high prevalence signifies an urgent need of amoebiasis diagnosis using advanced molecular tools to avoid overrepresentation and unnecessary chemotherapy.