Filiform papillae in the mucosa of the human vaginal wall

While giving the gross anatomy of the mucosa of the vagina, textbooks of Anatomy and Obstetrics and Gynaecology describe the presence of a median longitudinal ridge on its anterior wall (columna rugarum anterior) and another similar ridge (columna rugarum posterior) on its posterior wall is described, and transverse rugae separated by sulci of variable depth, extend bilaterally from these ridges. While conducting autopsy of female cases the routine examination of vaginal mucosa did not show the presence of longitudinal ridges. In addition, some small areas bearing filiform papillae were seen in the lower third of the vagina in young subjects. As these papillae have not been described earlier, it was decided to study them in detail using scanning electron microscopy.

A total of 215 vaginal specimens were studied. At autopsy the vagina was slit open on the lateral sides up to the upper ends of the lateral fornices. The anterior vaginal wall was turned up over the uterus and mucosa of both walls examined macroscopically. In 16 subjects, small pieces of vaginal mucosa bearing filiform papillae were cut out and processed for examination under scanning electron microscope (SEM) and a light microscope. In addition, vaginae of 55 married women (20-40 yr age) with complain of lower abdominal pain or infertility were examined particularly for the median longitudinal ridges on the vaginal walls.

At autopsy, the two median longitudinal ridges were not seen in any instance. Small variable areas of the lower third of the vagina showed the presence of filiform papillae on the two walls and at sides; they were prominent in the young individuals and tended to become absent in multipara and in old age. They were 2 to 3 in number on each wall. Histologically the papilla showed a core of highly vascular connective tissue covered by non-keratinized squamous epithelium. Immunoperoxidase staining with S-100 showed a large number of small nerve fibres in the subepithelial tissue which seemed to be more than in the surrounding areas not covered with papillae.

Anterior and posterior median longitudinal ridges were not seen on the vaginal mucosa in the autopsy specimens. In all autopsy specimens of young subjects between the ages of 15 and 40 yr, variable areas bearing filiform papillae were observed on the mucosa of the lower third of the vagina. Further studies need to be done to throw light on the role of these papillae.