Polymerase chain reaction confirmation of diagnosis of intestinal amebiasis in Puducherry.

Background Stool microscopy, the commonly used test for diagnosis of intestinal amebiasis, is unreliable as it does not differentiate Entamoeba histolytica, the causative agent for amebiasis, from non-pathogenic Entamoeba dispar and Entamoeba moshkovskii. Methods Two hundred and forty-six stool samples collected between January to February 2009, were examined microscopically for E. histolytica/E. dispar/E. moshkovskii complex cysts and trophozoites. Nested multiplex PCR targeting a 16 S-like rRNA gene for differential detection of all the three morphologically similar forms of E. histolytica, E. moshkovskii and E. dispar simultaneously was done on all microscopy positive stool samples. Results Forty-nine stool samples were positive for Entamoeba spp. by microscopy. Nested multiplex PCR for E. histolytica, E. moshkovskii and E. dispar was positive in only 19 of these samples, and only 6 of the 19 samples were positive for E. histolytica. Conclusion Stool microscopy grossly over-diagnosed intestinal amebiasis and is likely to result in unnecessary treatment with anti-protozoal drugs.

Acanthamoebae presenting as primary meningoencephalitis in AIDS.

A rare case of Acanthamoebae meningoencephalitis is diagnosed in cerebrospinal fluid (CSF) of a 24 years old male suffering from acquired immunodeficiency syndrome (AIDS) patient on the basis of bright field microscopy and culture growth on non-nutrient agar with Escherichia coli. This case illustrates that Acanthamoebae should be considered in the differential diagnosis of meningoencephalitis in AIDS in addition to tuberculosis and cryptococcus infection in tropical areas.