Amebae resembling Entamoeba gingivalis in the genital tracts of IUD users.

A total of 2,252 vaginopancervical (Fast) smears were studied as a continuation of an ongoing program to further investigate the occurrence of amebae in the genital tracts of women using intrauterine devices (IUDs). Of the 947 IUD users, 1% harbored trophic amebae. No amebae, however, were found in any of the 1,164 smears from non-IUD wearers. In all instances the amebae were associated with Actinomyces. Both organisms disappeared promptly after removal of the IUD. In preparations stained according to the Papanicolaou, iron-hematoxylin and Gomori-Wheatley trichrome methods, the amebae could be diagnosed as belonging to the genus Entamoeba. These trophozoites failed to stain with fluorescein-labeled anti-Entamoeba-histolytica serum. Although on the basis of the presently available evidence these trophozoites cannot be assigned with certainty to any known species, they appear to share many morphologic characteristics with Entamoeba gingivalis.