RESUMEN
Electron mlactimpic studies were performed on three primary and two early secondary syphilitic lesions from three patients. AZ of these patients had both secondary syphilitic lesions and chancres. There was no difference in the morphology and location of treponemes in these patients as compared to those who had only a chancre or only a syphilid reported earlier. This study revealed that Treponema pallida were principally located in the intercellular space of keratinocytes and exhacellular space of the dermis. Furthermore, these organisms were observed within histiocytes, endothelial cells, fibroblasts, lymphocytes and even plasma cells. The plasma cells had well developed endoplasmic reticulum, and in some, dilatation of the endoplasmic reticulum was noted. Many t mponemes were demonstrated in and around blood vessels. The vascular endothelial cells were proliferating and the basement membranes were thick.