[Incidence, morphology and diagnostic studies of Entamoeba gingivalis, Gros, 1849]. / Estudos de freqüência, morfologia e diagnóstico de Entamoeba gingivalis, Gros, 1849.

ABSTRACT

Entamoeba gingivalis is found only in its trophozoite form and it is postulated that its main transmission mechanism is through the kiss. E. gingivalis is considered pathogenic by some authors and commensal to others. It does not have a defined role in the installation of disease. To address some of this questions we studied a 100 patients who were seen through the Odontological Hospital from the Universidade Federal de Uberlândia in order to determine its frequency in the buccal cavity. The material were collected using swabs from four different buccal sites and the smears were stained by a modified Papanicolaou technique. The results revealed positivity index of 62%. The affinity of the dye to the food vacuole contents and to the ingested bacterias prevents clear visualisation of the central and peripherical chromatin constituents of the parasite's nucleus. Mouth washes with 3ml of saline from 10 patients, were used to evaluate which parasitological method of diagnosis (fresh, iron-haematoxylin stained, Giemsa and Papanicolaou) gives better visualisation of the parasite. The mouth washes sediment from fresh material revealed 100% of positivity and clear visualisation of the free form and locomotion of the trophozoites. No stained technique of the smear showed adequate visualisation, presenting the nucleus partially covered by the food vacuoles. In stained preparations by toluidine blue ultrastructure analysis of the morphology of parasite can be observed.