Resumen de Identificação fenotípica de Dientamoeba fragilis e Blastocystis hominis em pacientes atendidos no ambulatório do Hospital Universitário de Brasília: caracterização molecular preliminar de isolados diagnosticados
T. T. C. S. Minuzzi, C. A. Cuba Cuba
A high prevalence of Dientamoeba fragilis and Blastocystis hominis are reported on faecal samples collected from patients attending the ambulatory service of the University of Brasilia teaching hospital in Brasilia, Federal District, Brazil. Samples were collected directly into sodium acetate�acetic acid�formalin (SAF) and also as unfixed specimens. During a period of may 2008 and january 2009 a D. fragilis frequency of 31.5% (n = 89) among positive parasites samples and B. hominis 49.4% (n = 89), respectively, was recorded. From 46 individuals an association of D. fragilis and B. hominis were identified in 8 patients. Attempts of molecular identification were done and succesful results only achieved with the PCR/DNA of B. hominis. These results confirm a high frequency of both intestinal protozoa among a selected outpatient population. Of note, the higher presence of D. fragilis infections recorded is probably related to the diagnostic methods used, which are rarely followed in laboratories for the diagnosis of intestinal parasites. Clinical information was only available for a few of the patients with D. fragilis. For further work on its pathogenic role and prevalence among patients with gastrointestinal symptoms, immediate collection of fixed and unfixed specimens followed by staining routine procedures should be the mandatory procedures into diagnostic laboratories. The authors emphasize also the importance and need of Ferric haematoxylin staining assays on smears of faecal samples, on the basis of previous good direct microscopic observations of faecal specimens, for correct and accurate diagnosis of intestinal infections of these protozoan.
