Patogenicity of free-living amoebas isolates in body waters from Lima

Abstract

Objectives. To determine the presence of free-living amoeba (FLA) in water bodies from Lima department and assess their pathogenic ability in normal mice and immunosuppressed. Material and methods. Water samples were collected from rivers, lakes, swimming pools and wells in Lima, Peru. The isolation was performed by culture in non-nutritious agar with 2% of E. coli or E. aerogenes at 37 °C. Subsequently were injected into normal mice and immunosuppressed (betamethasone 1.4 mg/mL, a single dose) with a suspension of amoeba isolated. For the 15 days were assessed histological damage in both groups. Results. AVL were identified in 40/83 samples, 31.3% of the samples were developed in cultures. 26 strains were isolated from AVL of seven genera (Hartmannella, Acanthamoeba, Mayorella, Naegleria, Vahlkampfia, Vannella and Saccamoeba), Acanthamoeba was the most frequent (44.2%). AVL was found in 53.8% of immunosuppressed mice and 15.4% of the normal (p <0.05). Conclusions. AVL exist in water bodies from Lima, which have a potential pathogen in immunosuppressed patients, there is a risk of amoebic infection associated with these water sources.